Elastic worm gear assembly and its application

Abstract

The present invention discloses a mounting bracket for a telescope including a worm gear assembly. The worm gear assembly includes: a worm gear connected to a telescope holder such that movement of the worm gear about the worm gear axis causes movement of the holder about the worm gear axis; a worm having a worm body extending in a longitudinal direction and a thread spirally extending on the worm body about a worm axis orthogonal to the worm gear axis. The worm is supported by a base for rotational movement. The worm gear includes a plurality of teeth for engaging the worm thread such that rotation of the worm about the worm axis causes corresponding rotation of the worm gear and corresponding relative rotation about the worm gear axis between the holder and the base. The worm gear body defines a plurality of resiliently enhanced cuts spaced from the worm gear axis and extending through the worm gear body.

Description

Technical Field

[0001] The present invention relates to a worm gear assembly. Some embodiments provide an elastic worm gear assembly. Some embodiments provide an elastic worm gear assembly for a mounting bracket of a telescope or other optical instrument. Some embodiments provide a mounting bracket for a telescope or other optical instrument that includes an elastic worm gear assembly. Background Art

[0002] There are several types of movable mounting brackets for telescopes or other optical instruments. The two main types of telescope mounting brackets are equatorial mounting brackets and altitude-azimuth mounting brackets. These mounting brackets are configured such that a telescope (supported by the mounting bracket) can move on two orthogonal axes.

[0003] An equatorial mounting bracket compensates for the rotation of the Earth and provides single-axis tracking of celestial bodies. For example, a German equatorial mounting bracket typically has a right ascension shaft, a declination shaft, and a balance shaft. The right ascension shaft can rotate about the right ascension axis relative to the base. The declination shaft can rotate about the declination axis relative to the right ascension shaft. The declination axis is orthogonal to the right ascension axis. The balance shaft is mounted to one end of the right ascension shaft and extends from the right ascension shaft along a balance axis collinear with the declination axis.

[0004] An altitude-azimuthal mounting bracket, also known as an altazimuth mounting bracket or an alt-az mounting bracket, enables an optical instrument to rotate about two perpendicular axes (an azimuth axis and an altitude axis). The orientation of an optical instrument mounted on an alt-az mounting bracket corresponds to a set of coordinates called alt-az coordinates. Alt-az coordinates are typically expressed in terms of altitude and azimuth angle. Altitude represents the angular direction of the optical instrument around the altitude axis relative to the horizon. Altitude is typically expressed in the range of -90° to 90°, where 0° represents the horizon. The point at 90° is the point directly above the observer's head. The point directly above the observer's head is called the zenith. The azimuth angle represents the angular direction of the optical instrument around the azimuth axis and is expressed in the range of 0° to 360°. Typically, the azimuth angle is chosen to represent the true compass (relative to the magnetic azimuth) towards a point on the horizon and is measured eastward from the north celestial pole.

[0005] Worm gear assemblies are commonly used in both equatorial mounts and altitude-azimuth mounts to rotate a mounted telescope. A worm gear assembly includes a worm shaft (also known as a worm and a wormscrew) and a wormwheel (also known as a worm gear). The worm and the wormwheel cooperate with each other such that rotation of the worm about the worm axis causes corresponding rotation of the wormwheel about a wormwheel axis that is generally orthogonal to the worm axis. In a motorized mount, a motor typically acts on the worm shaft, which in turn mates with the wormwheel. In practice, the mechanical engagement between the wormwheel and the worm shaft is often either too loose or too tight. When the engagement is too loose, it may not be possible to adjust the direction of the mounted optical instrument with high precision. When the engagement is too tight, it may be difficult to turn the worm shaft, and this can result in increased friction and associated wear of the worm gear assembly.

[0006] There is a general desire for a worm gear assembly for a mount for a telescope or other optical instrument that enables easy operation, prevents premature wear, and / or enables precise adjustment of the mounted optical instrument.

[0007] The foregoing examples of the related art and the associated limitations are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of ordinary skill in the art upon reading the specification and studying the drawings. SUMMARY OF THE INVENTION

[0008] The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools, and methods that are exemplary and illustrative and do not limit the scope. In various embodiments, one or more of the above problems have been reduced or eliminated, while other embodiments address other improvements.

[0009] One aspect of the present invention provides a mounting for a telescope or other optical instrument. The mounting includes a holder for supporting the optical instrument mounted thereon, the holder being movable relative to a base about a worm axis by operation of a worm gear assembly. The worm gear assembly includes: a worm gear rigidly connected to the holder such that movement of the worm gear about the worm axis causes corresponding movement of the holder about the worm axis; and a worm including a worm body extending in a longitudinal direction and a thread spirally extending on the worm body about a worm axis longitudinally oriented orthogonal to the worm axis, the worm being supported by a base for rotational movement about the worm axis. The worm gear includes a generally disc-shaped worm gear body having a plurality of radially extending and circumferentially spaced teeth on a radially outermost peripheral surface for engaging the thread of the worm, whereby rotation of the worm about the worm axis causes corresponding rotation of the worm gear about the worm axis and corresponding relative rotation of the holder and the base about the worm axis through engagement of the teeth and the thread. The worm gear body is shaped to define a plurality of resiliently enhanced cuts spaced from the worm axis and extending through the worm gear body in a direction parallel to the worm axis.

[0010] Another aspect of the present invention provides a worm gear assembly for use with a mounting for a telescope or other optical instrument, the worm gear assembly including a holder for supporting the optical instrument mounted thereon, wherein operation of the worm gear assembly enables the holder to move relative to a base about a worm axis. The worm gear assembly includes: a worm gear rigidly connected to the holder such that movement of the worm gear about the worm axis causes corresponding movement of the holder about the worm axis; and a worm including a worm body extending in a longitudinal direction and a thread spirally extending on the worm body about a worm axis longitudinally oriented orthogonal to the worm axis, the worm being supported by a base for rotational movement about the worm axis. The worm gear includes a generally disc-shaped worm gear body having a plurality of radially extending and circumferentially spaced teeth on a radially outermost peripheral surface for engaging the thread of the worm, whereby rotation of the worm about the worm axis causes corresponding rotation of the worm gear about the worm axis and corresponding relative rotation of the holder and the base about the worm axis through engagement of the teeth and the thread. The worm gear body is shaped to define a plurality of resiliently enhanced cuts spaced from the worm axis and extending through the worm gear body in a direction parallel to the worm axis.

[0011] Each resiliently enhanced cut may be at least partially defined by a pair of continuous cut defining surfaces. The continuous cut defining surfaces may meet at a first discontinuity angle. The continuous cut defining surfaces may meet at a first discontinuity angle and a second discontinuity angle.

[0012] The continuous cut defining surfaces may be continuously curved. The continuous cut defining surfaces may be arcuate. The continuous cut defining surfaces may include different radii of curvature. The continuous cut defining surfaces may include different centers of curvature.

[0013] The resilience-enhancing cuts may each include a generally crescent-shaped cross-section in a direction of a cross-section orthogonal to the axis of the worm wheel.

[0014] Each resilience-enhancing cut may be defined by a cut-defining surface. The cut-defining surface may include a first arcuate portion and a second arcuate portion connected to the first arcuate portion by a pair of spaced-apart discontinuous portions. The first arcuate portion and the second arcuate portion may include different centers of curvature. The first arcuate portion and the second arcuate portion may include different radii of curvature.

[0015] Each of the resilience-enhancing cuts may be at least partially defined by a plurality of continuous cut-defining surfaces. At least one pair of the plurality of continuous cut-defining surfaces may meet at a discontinuous corner. The continuous cut-defining surfaces may be arcuate.

[0016] The resilience-enhancing cuts may each include a generally triangular cross-section in a direction of a cross-section orthogonal to the axis of the worm wheel.

[0017] Each resilience-enhancing cut may be at least partially defined by four continuous cut-defining surfaces. Two of the four continuous cut-defining surfaces may extend radially from the axis of the worm wheel, and the other two of the four continuous cut-defining surfaces may extend circumferentially around the axis of the worm wheel.

[0018] The continuous cut-defining surfaces may each extend in a direction parallel to the axis of the worm wheel.

[0019] The shape or position of the resilience-enhancing cuts may be such that any nominal radial line between the axis of the worm wheel and a tooth intersects at least one pair of continuous cut-defining surfaces, with one or more discontinuous portions therebetween. At least one nominal radial line may intersect a second pair of continuous cut-defining surfaces, with one or more discontinuous portions therebetween.

[0020] The resilience-enhancing cuts may be positioned around the axis of the worm wheel at uniform angular intervals.

[0021] The ratio of the volume of the resilience-enhancing cuts to the volume of the worm wheel may be between approximately 15% and approximately 45%, such that the mass of the worm wheel body provided is reduced by approximately 15% to approximately 45% compared to the mass of a worm wheel body made of solid material.

[0022] The base may be movable relative to a base support member, and the worm may be supported by the base such that movement of the base relative to the base support member causes corresponding movement of the axis of the worm and the axis of the worm wheel while maintaining their orthogonality therebetween.

[0023] In addition to the above - described exemplary aspects and embodiments, other aspects and embodiments will become apparent by reference to the drawings and by study of the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Exemplary embodiments are shown in the drawings. The embodiments disclosed herein and the drawings are to be considered illustrative and not restrictive.

[0025] Figure 1 is a perspective view of an exemplary embodiment of a worm gear assembly according to the present invention.

[0026] Figure 2A -C all show top views of exemplary embodiments of the resilient worm gear.

[0027] Figure 3 is including Figure 1 a perspective view of a height - azimuth mounting bracket of a resilient worm gear assembly.

[0028] Figure 4 is Figure 3 a partial perspective view of the height - azimuth mounting bracket.

[0029] Figure 5 is Figure 3 a perspective view of the height - azimuth mounting bracket with an exposed handle to show the elements housed therein.

[0030] Figure 6 is a cross - sectional view of the height - azimuth mounting bracket taken along line A - A of Figure 3 the height - azimuth mounting bracket. DETAILED DESCRIPTION

[0031] This document describes an elastic worm gear assembly. The elastic worm gear assembly can be used in a movable mount of a telescope or other optical instrument. The elastic worm gear assembly includes a worm and a worm wheel. The worm wheel is mounted to operatively engage with the worm such that rotation of the worm about the worm axis causes a corresponding rotation of the worm wheel about a worm wheel axis orthogonal to the worm axis. The worm includes a worm body extending in a longitudinal direction (generally parallel to the worm axis) and threads extending helically on an outer surface of the worm body about the worm axis. The worm wheel includes a generally disk-shaped worm wheel body that includes a plurality of radially extending and circumferentially spaced teeth at a radially outermost peripheral surface for engaging the threads of the worm. The worm wheel body is shaped to define a plurality of elastic reinforcement cuts that are spaced apart from the worm wheel axis and extend through the worm wheel body in a direction parallel to the worm wheel axis. The elastic reinforcement cuts impart enhanced elasticity to the worm wheel body (relative to a solid worm wheel body), such that the worm wheel has better elastic deformation in a radial direction toward the worm wheel axis (relative to a solid worm wheel body). In some embodiments, the elastic reinforcement cuts impart enhanced elasticity to the worm wheel body such that the worm wheel has better elastic deformation in other directions, such as in a direction parallel to the worm wheel axis and / or a circumferential direction (relative to a solid worm wheel body). In some embodiments, the ratio of the volume of the elastic reinforcement cuts to the volume of the worm wheel is between about 25% and about 45%, such that the mass of the worm wheel body provided is about 25% to about 45% lower than the mass of a worm wheel body made of solid material. When the elastic worm gear assembly is assembled into a telescope mount, the elastic reinforcement cuts contribute to achieving a closer-to-ideal engagement (e.g., neither too tight nor too loose) between the elastic worm wheel and the worm compared to a conventional worm gear assembly, thereby enabling precise adjustment of a telescope mounted on the telescope mount.

[0032] As used herein, unless the context otherwise indicates, the terms "elastic" and "elastically deformable" refer to the ability of the worm wheel to return to its initial shape after being deformed due to an applied force and the applied force is subsequently removed.

[0033] As used herein, unless the context otherwise indicates, the terms "about" and "substantially" refer to plus or minus 5%.

[0034] As used herein, unless the context otherwise indicates, the term "generally" is a general term. For example, a "worm wheel body that is generally disk-shaped" means that the worm wheel body has the overall shape of a disk, but its cross-sectional shape does not have to be perfectly circular.

[0035] As used herein, unless the context otherwise indicates, the term "continuous" or "continuous" or "continuously" means a smooth transition. In contrast, the terms "discontinuous" or "discontinuous" or "discontinuously" mean a non-smooth transition. For example, an elastomeric reinforcement incision may be defined by a pair of continuous incisions that define a surface, where the continuous incision-defined surfaces join (or meet) at a discontinuous (i.e., non-smooth, characterized by sharp corners) angle, where the radius of curvature of such a discontinuous angle is less than 2 cm, or in some embodiments, less than 1 cm, or in some embodiments, less than 5 mm, or in some embodiments, less than 2.5 mm.

[0036] The following description sets forth specific details in order to provide a more thorough understanding to those skilled in the art. It describes:

[0037] · A worm gear assembly, including an elastomeric worm gear; and

[0038] · A handheld elevation-azimuth mount including the worm gear assembly.

[0039] However, well-known elements may not be shown or described in detail to avoid unnecessarily obscuring the present disclosure. Accordingly, the specification and drawings are to be regarded as illustrative rather than restrictive.

[0040] worm gear assembly

[0041] Figure 1 A perspective view of a worm gear assembly 10 including a worm 12 and an elastomeric worm gear 14 is shown, with the worm 12 and the elastomeric worm gear 14 operatively engaged.

[0042] Focusing on the structural features of the worm 12, the worm 12 includes a worm body 20 extending along a longitudinal direction 17. At least a portion of the worm body 20 is circumscribed by a single thread 22. The single thread 22 extends helically around a longitudinally oriented worm axis 16 on the outer surface of the worm 12. The worm axis 16 extends in the longitudinal direction 17 and is aligned with the central axis of the worm body 20. In the illustrated embodiment, the single thread 22 is a V-thread having a V-shaped cross section. In other embodiments, the worm body 20 may be surrounded by multiple threads. The worm body 20 may be surrounded by non-V-threads. The entire worm body 20 may be surrounded by threads. The worm 12 may be a single-enveloping worm or a double-enveloping worm. The worm 12 may have threads forming a single starting point or multiple starting points. The worm 12 may be integrally formed and may be made of any suitable material. For example, the worm 12 may be made entirely of metal or plastic. The worm body 20 and the thread 22 may be made of different materials. For example, the worm body 20 is made of metal while the thread 22 is made of plastic. Generally, the worm 12 may be any threaded worm known in the art as long as the worm 12 can operably engage the worm gear 14 such that torque can be transmitted from the worm 12 to the worm gear 14.

[0043] Regarding the worm gear 14, the worm gear 14 includes a generally disk-shaped worm gear body 24. The disk-shaped worm gear body 24 of the illustrated embodiment has a centrally assembled hole portion 26, although in other embodiments, the centrally assembled hole portion 26 may be omitted. The disk-shaped worm gear body 24 includes a plurality of radially extending and circumferentially spaced teeth 28 on the radially outermost peripheral surface 32. The gap 34 between adjacent teeth 28 is shaped to engage the thread 22 of the worm 12 such that rotation of the worm 12 about the worm axis 16 causes corresponding rotation of the worm gear 14 about the worm gear axis 18. The worm gear axis 18 is orthogonal to the worm axis 16.

[0044] The shape of the worm gear body 24 is formed to define a plurality of elastomeric enhancement cuts 36 that impart a degree of elasticity to the worm gear body 24, thereby making the worm gear 14 more elastically deformable (relative to a solid worm gear body). In some embodiments, the elastomeric enhancement cuts impart enhanced elasticity to the worm gear body 24, thereby making the worm gear 14 more elastically deformable (relative to a solid worm gear body) in other directions, such as in a direction parallel to the worm gear axis and / or the circumferential direction. The elastomeric enhancement cuts 36 may be spaced apart from the worm gear axis 18. The elastomeric enhancement cuts 36 may extend through the worm gear body 24 in a direction parallel to the worm gear axis 18.

[0045] In order to provide a desired level of elasticity while maintaining a desired level of physical rigidity, in some embodiments, the ratio of the volume of the elasticity-enhancing cutout 36 to the volume of the worm wheel 14 is between approximately 15% and approximately 45%. Thus, the mass of the provided worm wheel body is about 15% to about 45% lower than the mass of a worm wheel body made of solid material. This ratio can be any value between about 15% and about 45%, for example, 17%, 20%, 25%, 28%, 31%, 33%, 35%, 37%, 39%, 41% and 43%. The ratio of the volume of the elasticity-enhancing cutout 36 to the volume of the worm wheel 14 can vary depending on the shape and location of the elasticity-enhancing cutout 36.

[0046] The elasticity-enhancing cutout 36 can have any suitable shape and size. Also, the elasticity-enhancing cutout 36 can be arranged at any suitable location. The shape, size, and / or location of the elasticity-enhancing cutout 36 can impart a certain degree of elasticity to the worm wheel body 24, such that the worm wheel 14 can be elastically deformed in the radial direction towards the worm wheel axis 18.

[0047] Focusing on the shape of the currently desired elasticity-enhancing cutout 36, the elasticity-enhancing cutout 36 can be oval, boomerang-shaped, rectangular, or triangular. The elasticity-enhancing cutouts 36 can be the same or different from each other.

[0048] In the illustrated embodiment, the elasticity-enhancing cutouts 36 have the same shape and size. For the sake of brevity, only one elasticity-enhancing cutout 36 will be described in detail below. The elasticity-enhancing cutout 36 is curved and forms a generally crescent shape in a cross-sectional direction perpendicular to the worm wheel axis 18. The elasticity-enhancing cutout 36 extends from an inner radius 38 to an outer radius 40 in an arcuate direction 42. The elasticity-enhancing cutout 36 is defined by a pair of continuous cut surfaces 48, 50. The continuous cut surfaces 48, 50 both extend through the worm wheel body 20 in a direction parallel to the worm wheel axis 18, although in some other embodiments, the continuous cut surfaces 48, 50 can extend through the worm wheel body 20 in a direction intersecting the worm wheel axis 18. The continuous cut surfaces 48, 50 are both arcuate, smooth, and have no sharp edges. The continuous cut surfaces 48, 50 of the illustrated embodiment have different centers of curvature and different radii of curvature, although this is not necessary. The continuous cut surfaces 48, 50 are joined and meet at discontinuity corners 52, 54. The radius of curvature at the discontinuity corners 52, 54 can be less than 2 cm; or in some embodiments, less than 1 cm; or in some embodiments, less than 5 mm; or in some embodiments, less than 2.5 mm.

[0049] Regarding the position of the resilience-enhancing cutout 36, this position may be affected by the shape and size of the resilience-enhancing cutout 36. This is because the shape, size, and position of the resilience-enhancing cutout 36 work together to impart the desired level of resilience to the worm wheel body 24 and the worm wheel 14.

[0050] In the illustrated embodiment, the position (and shape) of the resilience-enhancing cutout 36 is such that any nominal radial line between the worm wheel axis 18 and the tooth 28 intersects at least a pair of consecutive cutout defining surfaces 48, 50 having one or more discontinuity portions 52, 54 therebetween. Additionally, the position (and shape) of the resilience-enhancing cutout 36 is such that at least one nominal radial line intersects a second pair of consecutive cutout defining surfaces 48', 50' having one or more discontinuity portions 52', 54' therebetween. In other words, the resilience-enhancing cutouts 36 are positioned in a staggered manner such that one or more pairs of adjacent resilience-enhancing cutouts 36 overlap to a certain extent in the circumferential direction and are separated in the radial direction.

[0051] In the illustrated embodiment, the resilience-enhancing cutouts 36 are spaced apart at a uniform angular interval about the worm wheel axis 18.

[0052] In Figure 2A -C, some other embodiments of the resilience-enhancing cutout 36 are schematically shown. Figure 2A A worm wheel 14A having a plurality of resilience-enhancing cutouts 36A is shown. Each resilience-enhancing cutout 36A is defined by four consecutive cutout defining surfaces 56, 58, 60, 62. The resilience-enhancing cutout 36A includes a rectangular cross-section taken in a cross-sectional direction orthogonal to the worm wheel axis 18A. In other words, each resilience-enhancing cutout 36A is defined by four consecutive surfaces 56, 58, 60, 62. Figure 2B A worm wheel 14B having a plurality of resilience-enhancing cutouts 36B is shown. Each of the resilience-enhancing cutouts 36B is defined by a consecutive cutout defining surface 56B. The consecutive cutout defining surface 56B includes a first curved portion 58B and a second curved portion 60B connected to the first curved portion 58B. The first curved portion 58B and the second curved portion 60B have the same center of curvature, although they have different radii of curvature. The resilience-enhancing cutout 36B includes a generally boomerang-shaped cross-section in a cross-sectional direction orthogonal to the worm wheel axis 18B. Figure 2CShows a worm gear 14C having a plurality of elastomeric reinforcing cuts 36C. Each of the elastomeric reinforcing cuts 36C includes an elliptical cross-section taken in a direction orthogonal to the worm gear axis 18C. In other words, each elastomeric reinforcing cut 36C is defined by a continuous cut-defining surface. Those skilled in the art will understand that the elastomeric reinforcing cuts can have any suitable shape and size to provide the desired elastic properties for the worm gear 14. Other possible embodiments include elastomeric reinforcing cuts defined by three continuous cut-defining surfaces. The three continuous cut-defining surfaces can be curved and can meet at three discontinuous corners. Each elastomeric reinforcing cut can include a generally triangular cross-section in a cross-sectional direction orthogonal to the worm gear axis.

[0053] The worm gear 14 can be integrally formed and can be made of any suitable material. In some embodiments, the worm gear 14 is made entirely of metal or plastic. In some other embodiments, the worm gear body 24 and the teeth 32 are made of different materials. For example, the worm gear body 24 can be made of metal, while the teeth 32 can be made of plastic.

[0054] In operation, the worm 12 and the elastomeric worm gear 14 are mounted in operative engagement with each other such that when the worm 12 rotates about the worm axis 16, the worm 12 acts on the worm gear 14 and causes the worm gear 14 to rotate about the worm gear axis 18. The worm rotation axis 16 and the worm gear rotation axis 18 are oriented perpendicular to each other and do not intersect. The threads 22 engage the teeth 32 such that the rotational movement of the worm 12 acts on the worm gear 14 and drives the worm gear 14. The worm gear 14 can be elastically deformed in the radial direction towards the worm gear axis 18 (e.g., more elastically deformable than a solid worm gear). In some embodiments, the elastomeric reinforcing cuts 36 impart enhanced elasticity to the worm gear body 24, thereby making the worm gear 14 more elastically deformable in other directions, such as in a direction parallel to the worm gear axis and / or in the circumferential direction (relative to a solid worm gear body). When the threads 22 are received in the gap 34 between adjacent teeth 32, the worm 12 can press on the worm gear 14, whereby the worm gear 14 is elastically compressed inwardly towards the worm gear axis 18. The compressive force acts on the outer peripheral surface 30, thereby causing the worm gear 14 to deform radially inwardly. The elastic deformation of the worm gear 14 facilitates engagement, and backlash between the worm 12 and the worm gear 14 is minimized as the worm gear 14 rotates about the worm axis 16.

[0055] handheld elevation-azimuth mounting bracket including an elastic worm gear assembly

[0056] The worm gear assembly 10 can be incorporated into the mount of a telescope or other optical instrument. When incorporated into the mount, the worm gear assembly 10 enables precise adjustment of the telescope mounted on the mount. This is because the resiliently enhanced cutouts 36 and the corresponding elastic deformation of the worm gear 14 urge an ideal engagement between the resilient worm gear 14 and the worm 12 that is neither too tight nor too loose (e.g., to mitigate backlash). Those skilled in the art will understand that the mount in which the worm gear assembly is used can be any type of movable mount for a telescope or other optical instrument, including equatorial mounts and altitude-azimuth mounts.

[0057] An example embodiment of a mount 100 incorporating the worm gear assembly 10 is shown in Figures 3-6 FIG. 5. The mount 100 is a hand-held altitude-azimuth mount in which precise adjustment of the altitude-azimuth coordinates can be a challenge. Due to the elastic deformability of the worm gear 14, the deployment of the worm gear assembly 10 in the hand-held altitude-azimuth mount 100 facilitates relatively accurate altitude and / or azimuth adjustment (relative to a mount incorporating a solid worm gear assembly).

[0058] The hand-held altitude-azimuth mount 100 includes a holder 106 for supporting an optical instrument (not shown) mounted thereon. By operation of an altitude rotation mechanism 102 and an azimuth rotation mechanism 104, respectively, the holder 106 is rotatably movable relative to a base 108 about an altitude axis 110 and an azimuth axis 112. In terms of its worm gear assembly 10, the structural features of the altitude rotation mechanism 102 and the azimuth rotation mechanism 104 can be substantially the same. For the sake of brevity, only the altitude rotation mechanism 102 will be described in detail below.

[0059] As Figures 3-6 shown, the altitude rotation mechanism 102 includes the worm gear assembly 10, which includes a worm 12 rotatable about a worm axis 16 and a worm gear 14 rotatable about a worm gear axis 18. The worm 12 is supported for rotational movement about the worm axis 16 in a sleeve 116 ( Figure 3 )). The sleeve 116 can form part of a holder support member 111 or can be securely mounted to the holder support member 111. The holder support member 111 supports the holder 106 and rotates with the holder 106 about the azimuth axis 112 by the action of the azimuth rotation mechanism 104. As will be described in more detail below, the holder 106 rotates relative to the holder support member 111 about the altitude axis 110 by the action of the altitude rotation mechanism 102.

[0060] As Figure 4As best shown, the worm 12 of the altitude rotation mechanism 102 is rotatable within the sleeve 116 about its worm axis 16. The sleeve 116 is positioned such that rotation of the worm 12 causes corresponding rotation of the worm gear 14 about the worm gear axis 18, which may be collinear with the altitude axis 110. The worm gear 114 is rotatably supported on the rod bearing 118 of the retainer support member 111 such that the worm gear 114 is rotatable about the altitude axis 110 (worm gear axis 18) by rolling on the surface of the rod bearing. In the illustrated embodiment, the worm gear 114 includes a key ring 115 having a pair of keyways 115A. The retainer 106 is fitted onto the key ring 115 such that corresponding key projections (not shown) of the retainer 106 fit into the keyways 115A. In this way, rotation of the worm 12 about the worm axis 16 (e.g., by a user in some embodiments or by a suitably configured electric motor in some embodiments) causes corresponding rotation of the worm gear 14 about the altitude axis 110 (worm gear axis 18). When the worm gear 14 rotates, the key ring 115 rotates, which in turn causes the retainer 106 to rotate about the altitude axis 110 by engaging the key projections of the retainer 106 into the keyways 115A. As described above, the worm gear 14 includes a notch 36 (not specifically enumerated in Figures 4-6 ), which provides the worm gear 14 (relative to a solid worm gear) with a relatively high degree of elastic deformation ability and brings corresponding benefits to the altitude rotation mechanism 102 (as described in other parts here).

[0061] Those skilled in the art will understand that the altitude rotation mechanism 102 may be configured to have other specific configurations that use the worm gear assembly 10 to facilitate rotational movement of one component (e.g., the retainer 106) relative to another component (e.g., the retainer support member 111) about the altitude axis 110, and utilize the worm gear assembly 10 and the deformable worm gear 14. Those skilled in the art will understand that the azimuth rotation mechanism 104 may be similarly configured to have a similar configuration that uses the worm gear assembly 10 to facilitate rotational movement of one component (e.g., the retainer support member 111) relative to another component (e.g., the base 108) about the azimuth axis 112, and utilizes the worm gear assembly 10 and the deformable worm gear 14.

[0062] In some embodiments, the mounting bracket 100 may be an equatorial mounting bracket that includes a retainer for supporting an optical instrument mounted thereon, the retainer being rotatable about the right ascension and declination axes relative to the base by corresponding right ascension and declination rotation mechanisms, where one or both of the right ascension and declination rotation mechanisms include a worm gear assembly 10 having a deformable worm gear 14.

[0063] In some embodiments, the worm gear assembly 10 may be operated by an electric motor. For example, rotation of the worm 12 may be driven by an electric motor.

[0064] Although many exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize some of their modifications, permutations, additions, and sub-combinations. Accordingly, the appended claims and the claims hereafter introduced are intended to be construed to include all such modifications, permutations, additions, and sub-combinations as are consistent with the broadest interpretation of this specification.

Claims

1. A mounting bracket for a telescope or other optical instrument, comprising: A retainer for supporting an optical instrument mounted thereon, the retainer being movable relative to a base about a worm axis by operation of a worm gear assembly; Said worm gear assembly comprising: A worm gear rigidly connected to said retainer such that movement of said worm gear about said worm axis causes a corresponding movement of said retainer about said worm axis; A worm comprising a worm body extending in a longitudinal direction and a thread spirally extending on said worm body about a worm axis longitudinally oriented orthogonal to said worm axis, said worm being supported by said base for rotational movement about said worm axis; Said worm gear comprises a generally disc-shaped worm gear body having a plurality of radially extending and circumferentially spaced teeth on its radially outermost peripheral surface for engaging the thread of said worm, whereby engagement of said teeth and said thread causes rotation of said worm about said worm axis to cause a corresponding rotation of said worm gear about said worm axis and a corresponding relative rotation of said retainer and said base about said worm axis; and Said worm gear body is shaped to define a plurality of elastomeric enhancement cuts spaced from said worm axis and extending through said worm gear body in a direction parallel to said worm axis, said elastomeric enhancement cuts enhancing the elasticity of said worm gear in the radial direction relative to a solid worm gear body.

2. The mounting bracket according to claim 1, wherein, Each of said elastomeric enhancement cuts is at least partially defined by a pair of continuous cut defining surfaces.

3. The mounting bracket according to claim 2, wherein, Said continuous cut defining surfaces meet at a first discontinuity angle.

4. The mounting bracket according to claim 3, wherein, Said continuous cut defining surfaces meet at said first discontinuity angle and at a second discontinuity angle.

5. The mounting bracket according to any one of claims 2 to 4, wherein, Said continuous cut defining surfaces are continuously curved.

6. The mounting bracket according to any one of claims 2 to 4, wherein, Said continuous cut defining surfaces are arcuate.

7. The mounting bracket according to claim 5, wherein, Said continuous cut defining surfaces include different radii of curvature.

8. The mounting bracket according to claim 5, wherein, Said continuous cut defining surfaces include different centers of curvature.

9. The mounting bracket according to any one of claims 2 to 4, wherein, Said elastomeric enhancement cuts each include a generally crescent-shaped cross-section in a cross-sectional direction orthogonal to said worm axis.

10. The mounting bracket according to claim 1, wherein: Each of said elastomeric enhancement cuts is defined by a cut defining surface; Said cut defining surface includes a first arcuate portion and a second arcuate portion, said second arcuate portion being connected to said first arcuate portion by a pair of spaced discontinuities; and Said first arcuate portion and said second arcuate portion include different centers of curvature.

11. The mounting bracket according to claim 1, wherein: Each of said elastomeric enhancement cuts is defined by a cut defining surface; Said cut defining surface includes a first arcuate portion and a second arcuate portion, said second arcuate portion being connected to said first arcuate portion by a pair of spaced discontinuities; and Said first arcuate portion and said second arcuate portion include different radii of curvature.

12. The mounting bracket according to claim 1, wherein, Each of said elastomeric enhancement cuts is at least partially defined by a plurality of continuous cut defining surfaces.

13. The mounting bracket according to claim 12, wherein, At least one pair of said plurality of continuous cut defining surfaces meet at a discontinuity angle.

14. The mounting bracket according to claim 13, wherein, Said continuous cut defining surfaces are arcuate.

15. The mounting bracket according to any one of claims 12 to 14, wherein, The elastic strengthening cuts each include a generally triangular cross-section in a cross-sectional direction orthogonal to the axis of the worm wheel.

16. The mounting bracket according to claim 1, wherein, Each of the elastic strengthening cuts is at least partially defined by four consecutive cut defining surfaces.

17. The mounting bracket according to claim 16, wherein, Two of the four consecutive cut defining surfaces extend radially from the axis of the worm wheel, and the other two of the four consecutive cut defining surfaces extend circumferentially around the axis of the worm wheel.

18. The mounting bracket according to any one of claims 12 to 14, wherein, The consecutive cut defining surfaces all extend in a direction parallel to the axis of the worm wheel.

19. The mounting bracket according to any one of claims 2 to 4, wherein The shape or position of the elastic strengthening cuts is such that any nominal radial line between the axis of the worm wheel and the teeth intersects at least one pair of consecutive cut defining surfaces, with one or more discontinuities therebetween.

20. The mounting bracket according to claim 19, wherein, At least one nominal radial line intersects a second pair of consecutive cut defining surfaces, with one or more discontinuities therebetween.

21. The mounting bracket according to claim 1, wherein, The elastic strengthening cuts are positioned at uniform angular intervals around the axis of the worm wheel.

22. The mounting bracket according to claim 1, wherein, The ratio of the volume of the elastic strengthening cuts to the volume of the worm wheel is between about 15% and about 45%, thereby providing a mass of the worm wheel body that is about 15% to about 45% less than the mass of the worm wheel body if made of solid material.

23. The mounting bracket according to claim 1, wherein, The base is movable relative to a base support member, and the worm is supported by the base such that movement of the base relative to the base support member causes corresponding movement of the axis of the worm and the axis of the worm wheel while maintaining orthogonality therebetween.

24. A worm wheel assembly for a mount of a telescope or other optical instrument, comprising a holder for supporting an optical instrument mounted thereon, operation of the worm wheel assembly enabling the holder to move relative to a base about the axis of the worm wheel, the worm wheel assembly comprising: A worm wheel rigidly connected to the holder such that movement of the worm wheel about the axis of the worm wheel causes corresponding movement of the holder about the axis of the worm wheel; A worm comprising a worm body extending in a longitudinal direction and threads extending helically on the worm body about a worm axis longitudinally oriented orthogonal to the axis of the worm wheel, the worm being supported by the base for rotational movement about the worm axis; The worm wheel includes a generally disk-shaped worm wheel body, the worm wheel body including a plurality of radially extending and circumferentially spaced teeth on a radially outermost peripheral surface for engaging the threads of the worm, whereby engagement of the teeth with the threads causes rotation of the worm about the worm axis to cause corresponding rotation of the worm wheel about the axis of the worm wheel, and corresponding relative rotation of the holder and the base about the axis of the worm wheel; and The worm wheel body is shaped to define a plurality of elastic strengthening cuts spaced from the axis of the worm wheel and extending through the worm wheel body in a direction parallel to the axis of the worm wheel, the elastic strengthening cuts enhancing the elasticity of the worm wheel in a radial direction relative to a solid worm wheel body.

25. The worm gear assembly according to claim 24, wherein, Each of the elastic strengthening cuts is at least partially defined by a pair of consecutive cut defining surfaces.

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