阅读说明：本技术 自适应径向密封调节器 (Self-adaptive radial sealing regulator ) 是由 R.S.阿门 E.C.伊尔德利 于 2020-02-27 设计创作，主要内容包括：本文中描述了改进的径向气动调节器系统、装置和方法。实施例可以包括具有自适应径向密封件的调节器,以防止空气泄漏,提供增加的空气供应使用效率,并且有利于系统的更高效制造和组装。调节器系统可以用在诸如针对气动电动工具的应用中。(Improved radial pneumatic regulator systems, devices, and methods are described herein. Embodiments may include a regulator with an adaptive radial seal to prevent air leakage, provide increased air supply usage efficiency, and facilitate more efficient manufacturing and assembly of the system. The regulator system may be used in applications such as for pneumatic power tools.)

1. A radial seal adjuster system comprising:

a housing having a cylindrical opening with a central axis;

a bushing configured to fit inside the cylindrical opening;

an adjuster having an axial length and a forward end and a rearward end and configured to fit inside the bushing;

the bushing has a first plurality of apertures disposed to a plane oriented generally proximate a mid-section of a length of the adjuster and a second plurality of apertures disposed to a plane oriented generally proximate the front end of the adjuster.

2. The system of claim 1, wherein the first plurality of orifices comprises a feed gas orifice for feed gas entering an axially central section of the conditioner.

3. The system of claim 1, wherein the regulator comprises an axially central section comprising a first central bore and a second central bore.

4. The system of claim 3, wherein the first central chamber and the second central chamber are separated by a central gas guide extending along a diameter of the regulator.

Technical Field

The present invention relates to a regulator, such as may be employed in a pneumatic tool. The regulator may include an adaptive radial seal that may accommodate sub-optimal part shapes while still achieving a good air seal. Additional features and advantages are realized.

Disclosure of Invention

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

The present invention relates to a novel and improved radial actuator such as may be used in power tools that utilize compressed air as a motive force, or otherwise use a hydraulic or fluid drive system.

Typical cylindrical regulators include a cylindrical regulator and a cylindrical housing that need to be rotated relative to each other to direct pressurized air or other gas to the various flow passages, and that rely on a tight radial fit between the regulator and the housing to provide a sealed environment with a reasonably allowable minimum leakage of pressurized air. This required tight radial fit presents problems with rotation of the regulator and inherent leakage in the design due to manufacturing tolerances and part fit.

One aspect of the present invention includes including a spring-loaded member in the regulator that can accommodate out-of-round conditions in either or both of the regulator and/or the cylindrical housing, and can also provide a looser fit between the regulator body and the cylindrical housing, thus accommodating manufacturing and operational convenience, while still achieving a higher degree of air-sealing between the regulator and the cylindrical housing.

Another aspect of the invention may include a radial seal adjuster system comprising: a housing having a cylindrical opening with a central axis; a bushing configured to fit inside the cylindrical opening; an adjuster having an axial length and a forward end and a rearward end and configured to fit inside the bushing; the bushing has a first plurality of apertures disposed to a plane oriented generally proximate a mid-section of a length of the adjuster and a second plurality of apertures disposed to a plane oriented generally proximate a front end of the adjuster.

Another aspect of the invention may include a radial seal adjuster system comprising: a housing having a cylindrical opening with a central axis; a bushing configured to fit inside the cylindrical opening; an adjuster having an axial length and a forward end and a rearward end and configured to fit inside the bushing; the liner has a first plurality of apertures disposed to open into a plane oriented generally proximate a mid-section of the length of the conditioner and a second plurality of apertures disposed to open into a plane oriented generally proximate a front end of the conditioner, and wherein the first plurality of apertures includes a charge gas aperture for entry of charge gas into an axially central section of the conditioner.

Another aspect of the invention may include a radial seal adjuster system comprising: a housing having a cylindrical opening with a central axis; a bushing configured to fit inside the cylindrical opening; an adjuster having an axial length and a forward end and a rearward end and configured to fit inside the bushing; the bushing has a first plurality of apertures disposed to open into a plane oriented generally proximate a mid-section of a length of the adjuster and a second plurality of apertures disposed to open into a plane oriented generally proximate a forward end of the adjuster, wherein the adjuster includes an axially central section including a first central cavity and a second central cavity.

Another aspect of the invention may include a radial seal adjuster system comprising: a housing having a cylindrical opening with a central axis; a bushing configured to fit inside the cylindrical opening; an adjuster having an axial length and a forward end and a rearward end and configured to fit inside the bushing; the bushing has a first plurality of apertures disposed to open into a plane oriented generally proximate a mid-section of a length of the regulator and a second plurality of apertures disposed to open into a plane oriented generally proximate a forward end of the regulator, wherein the regulator includes an axially central section including a first central cavity and a second central cavity, and wherein the first and second central cavities are separated by a central gas guide extending along a diameter of the regulator.

Drawings

The drawings illustrate implementations of the concepts conveyed in the present application. Features of the illustrated implementations may be more readily understood by reference to the following description considered in connection with the accompanying drawings.

Fig. 1 illustrates an exemplary illustration of a power tool according to at least one embodiment.

Fig. 2 illustrates an exemplary view of a rear exterior of the power tool of fig. 1 in accordance with at least one embodiment.

FIG. 3 illustrates a cross-sectional view of the handle and rear portion of the power tool of FIG. 1 in accordance with at least one embodiment.

FIG. 4 illustrates a rear exterior view of a regulator in accordance with at least one embodiment.

FIG. 5 illustrates a front view of the regulator of FIG. 4 in accordance with at least one embodiment.

FIG. 6 illustrates a side view of the regulator of FIG. 4 in accordance with at least one embodiment.

Fig. 7 illustrates an exemplary side view of the regulator of fig. 6 with the regulator rotated 90 degrees from the view of fig. 6 in accordance with at least one embodiment.

FIG. 8 illustrates a cross-sectional side view of a regulator, bushing, and back cover in accordance with at least one embodiment.

Fig. 9 illustrates a cross-sectional elevation view of the regulator, bushing, and back cover with the regulator in a forward high power position, in accordance with at least one embodiment.

Fig. 10 illustrates an oblique perspective view of a front view of the regulator, bushing, and back cover with the back cover unattached to the drive body in accordance with at least one embodiment.

FIG. 11 illustrates an interior elevation view of a regulator with a rear cover in accordance with at least one embodiment.

FIG. 12 illustrates an angled view of a bushing containing a regulator and vanes in accordance with at least one embodiment.

FIG. 13 illustrates an angled rear view of an adjuster and bushing in accordance with at least one embodiment.

FIG. 14 illustrates an angled rear view of the adjuster and bushing of FIG. 14 in accordance with at least one embodiment.

FIG. 15 illustrates an enlarged rear view of the power tool and regulator of FIG. 1 in accordance with at least one embodiment.

FIG. 16 illustrates an example of a detent system in accordance with at least one embodiment.

Fig. 17a-17d illustrate cross-sectional views of the assembly and airflow at various power settings.

FIG. 18 illustrates an integrally formed blade and biasing member in accordance with at least one embodiment.

FIG. 19 illustrates a perspective view of a blade in accordance with at least one embodiment.

FIG. 20 illustrates a side view of a blade in accordance with at least one embodiment.

Fig. 21 illustrates a side view of the bushing and adjuster assembly of fig. 13 in a slightly rotated view in accordance with at least one embodiment.

FIG. 22 illustrates a top cross-sectional view of a rear cover and handle in accordance with at least one embodiment.

Detailed Description

The following detailed description refers to the accompanying drawings and various embodiments of the present invention.

Fig. 1 illustrates an exemplary illustration of a power tool 10 according to at least one embodiment of the present disclosure. As also shown in fig. 1, the power tool 10 includes a handle portion 12 and a drive body 14. The drive body 14 also includes a rear cover 16. Also shown in fig. 1 is a drive shaft 22 of the power tool.

Fig. 2 illustrates an exemplary view of the rear exterior of the power tool of fig. 1 in accordance with at least one embodiment of the present invention. Shown in fig. 2 is rear cover 16 and regulator 18. A grease port (grease port) 20 is located in the center of the rear cover 16. The rear cover 16 may also be referred to as a housing.

Fig. 3 illustrates a cross-sectional view of the handle 12 and rear portion 24 of the power tool 10 of fig. 1, in accordance with an embodiment of the present invention. Also shown in cross-sectional view are the regulator 18, the rear cover 16 and the gasket 17. The regulator 18 includes a rear end 26 and a front end 28. In some embodiments, a shoulder 30 of the rear cover 16 may be used to retain the regulator 18 in a functional position inside the rear cover 16. Also shown is the motor 32 of the power tool 10, as well as the charge gas coupling 13 and the exhaust gas passageway 11.

Fig. 4 illustrates an external rear view of the regulator 18 in accordance with at least one embodiment of the present invention. Shown is a grip 34 to facilitate operator rotation of the adjuster 18. FIG. 5 illustrates a front view of the regulator 18 in accordance with at least one embodiment. Shown are a first air passage slot 36 and a second air passage slot 37. In some embodiments, first air passage slot 36 and second air passage slot 37 may be used to direct exhaust gases. The terms "air" and "gas" or "gases" are used interchangeably herein, and embodiments of the present invention may operate with air or non-atmospheric gas mixtures.

FIG. 6 illustrates a side view of the regulator 18 in accordance with at least one embodiment. Shown are the regulator 18, the rear end 26, the front end 28, the first O-ring groove 38, the second O-ring groove 39, and a first central cavity 40 in the central portion 27 of the regulator 18.

FIG. 7 illustrates an exemplary top view of one embodiment of the adjuster of FIG. 6 showing a view of the adjuster rotated 90 from the view of FIG. 6, and the 90 rotation being in a clockwise direction from the perspective of FIG. 4. The central portion 27 of the regulator 18 comprises two central chambers: a first central lumen 40 and a second central lumen 41. The regulator 18 also includes a central gas guide 62. Also shown in fig. 7 are first and second central bores 40 and 41 and first and second O- rings 42 and 43. Also shown is a first vane 44. In the embodiment shown in fig. 7, the first vane 44 does not extend in the axial direction so as to extend below the first and second O- rings 42, 43. O- rings 42 and 43 extend circumferentially around the regulator 18 and are disposed in the O- ring grooves 38 and 39, respectively.

In some embodiments, the present invention includes spring-loaded vanes that provide an optimal radial seal between the regulator and the closure bushing or housing without requiring a tight OD/ID (outer/inner diameter) clearance fit, and which can accommodate out-of-roundness conditions of either or both of the regulator and/or the closure bushing or housing.

Fig. 8 illustrates a cross-sectional view of the adjuster 18, bushing 48, rear cover 16, and shoulder 30. Also shown are the first leaf 44 and the second leaf 45 with associated first spring 46 and second spring 47. In the embodiment of fig. 8, the first spring 46 and the second spring 47 are compression springs. The first and second vanes 44, 45 are positioned in the first and second slots 52, 53 of the regulator 18, respectively. The first spring 46 and the second spring 47 are positioned in the first spring groove 54 and the second spring groove 55. First and second springs 46, 47, respectively, are used to bias first and second vanes 44, 45 in a radially outward direction toward bushing 48, with first and second vanes 44, 45 sealing against radially inner surface 78 of bushing 48. In the embodiment of fig. 8, the first and second vanes 44, 46 extend in an axial direction toward the rear and front ends 26, 28 of the regulator 18 so as to oppose the first and second O- rings 42, 43. It should be noted that in another embodiment, the embodiment of fig. 7, neither the first blades 44 nor the second blades 45 extend in the axial direction below the first O-ring 42 and the second O-ring 43.

In the embodiment of FIG. 8, the first lobe 44 includes a first notch 50 and a second notch 51 that align with the first O-ring groove 38 and the second O-ring groove 39 to accommodate proper positioning of the O- rings 42 and 43. Similarly, the second vane 45 includes a third notch 80 and a fourth notch 81 that align with the first and second O- ring grooves 38 and 39 to accommodate the proper positioning of the O- rings 42 and 43. As also shown in fig. 19, each of the vanes 44 and 45 includes a vane sealing surface 140, the vane sealing surface 140 being supported against the radially inner surface 78 of the bushing 48. In some embodiments, the blade may comprise more than one material, and in some embodiments may have a separate material comprising the blade sealing surface 140, in some embodiments such a surface may be a rubberized material. The vane sealing surface may be planar and generally perpendicular to the vane sidewall 144. Further, each of the vanes 44 and 45 may include a spring seat slot 142. As shown in fig. 20, the vane may also include a vane sealing surface having a circular profile when viewed in cross-section.

Further, in the embodiment shown in fig. 8, O- rings 42 and 43 may facilitate efficient assembly of regulator 18, bushing 48, and other sub-assemblies into back cover 16. Due to leakage concerns and tolerance requirements, the regulator assembly of certain embodiments of the present invention may present difficulties in assembly. However, in certain embodiments enabled by the biasing vane structures of certain embodiments, assembly complexity may be significantly reduced. Moreover, because the biasing blade assembly can accommodate greater per-workpiece tolerances, the per-workpiece cost of the components of certain embodiments can be greatly reduced. The O- rings 42 and 43 serve to retain the vanes 44 and 45 in the slots 52 and 53 during assembly of the regulator 18 into the bushing 48. In other words, during assembly, the springs 46 and 47 may be inserted into the spring grooves 54 and 55, then the vanes 44 and 45 may be inserted into the slots 52 and 53, then the O- rings 42 and 43 may be placed in the O- ring grooves 38 and 39 and span the notches 50 and 51, thereby retaining the vanes 44 and 45 in the slots 52 and 53 when the regulator, spring, vane, and O-ring assembly is inserted into the bushing 48, while still allowing the vanes 44 and 45 to be radially spring biased against the radially inner surface 78 of the bushing 48. The complete assembly of the adjuster 18 and bushing 48 may then be inserted into the rear cover 16 and retained in the axial direction by the shoulder 30. Thereafter, as shown in fig. 3, the rear cover 16 may be attached to the power tool 10 as part of the rear portion 24. In other words, embodiments of the present design create their own blade retention in their respective slots during assembly.

In various embodiments, blades 41 and 42 may have different lengths. In some embodiments, the vanes do not extend in the axial direction to contact the O-ring, and in some embodiments, the vanes may extend to contact the O-ring. In some other embodiments, the O-ring may extend to face the O-ring. In other embodiments, they may extend beyond the notches 50 and 51 to extend axially outward beyond the O-ring toward one or both of the aft end 26 and/or the forward end 26 of the bushing 48.

Different embodiments of springs 46 and 47 may be used in different embodiments of the present invention. In the embodiment of fig. 8, the spring comprises a compression spring. In some embodiments, the spring may comprise a leaf spring or a torsion spring. In some embodiments, each vane may be radially biased in an outward direction by two or more springs paired laterally along each of the slots 52 and 53. In another embodiment, the radially outward pressure may be generated by forming the vanes by an integral molding process, whereby each vane is integrally molded with a radially inward flexible or resilient portion that holds the vane in a radially outward biased manner toward the radially inner surface 78 of the bushing 48 when the vane is installed in the slots 52 and 53. The flexible portion of the blade serves to create a biasing force in a radially outward direction when the integrally molded blade is inserted into its corresponding recess. An illustrative example of such an integrally molded blade is shown in fig. 18, which shows a blade 44a having two resiliently flexible arms 124a and 124b, the resiliently flexible arms 124a and 124b producing the desired biasing force when the blade 44a is inserted into the slot 52 or 53. Other methods may be used to generate a radial biasing force that urges the vanes against the radially inner surface 78 of the bushing 48. FIG. 18 also illustrates another feature of some embodiments. Shown (by dashed lines) are asymmetric notches 148a and 148 b. In these asymmetric notches, the portions 150a and 150b of the notch are not circular with a constant radius relative to the curve of the notches 148a and 148b near their location of contact with the vane sealing surface 140. In contrast, portions 150a and 150b have a more vertical orientation than a circle. This orientation facilitates radially outward movement of the vanes and limits the possible tendency of the vanes to become caught in the possible compression of O- rings 42 and 43 and thus to be restricted in the freedom of the vanes to move radially outward. The lower portions 152a and 152b of the asymmetrical notches 148a and 148b are more circular in shape and therefore are configured to easily seal against the O- rings 42 and 43 to prevent air pressure leakage.

In certain embodiments of the invention, the vanes seal against a liner or casing surface and are biased in a radially outward direction. In other embodiments, the vanes may be positioned in a radially inwardly biased orientation to bear against a sealing surface, such as a bushing, adjuster, or other structure or component.

Also shown in fig. 8 are a stop pin 56, a stop spring 58, and a stop cavity 60. The stop assembly works with the bushing 48 or the rear cover 16 to provide tactile feedback to the user of the power tool 10 as the grip 34 and the adjustor 18 rotate through various preset rotation points, such as the preset rotation points shown in fig. 15. Other methods or systems may be used to maintain the regulator 18 in various preset rotational points.

Fig. 9 illustrates a cross-sectional elevation view of the regulator 18, bushing 48, and back cover 16 taken along line CC of fig. 8 with the regulator in the forward high power position 82 of fig. 15.

Also shown in fig. 9 is a cross-sectional view of the central portion 27 of the regulator 18. The central portion 27 includes a central gas guide 62 therein, the central gas guide 62 having a first end 64 and a second end 66. The center gas guide 62 rotates about an axis 86 of the center gas guide 62, which axis 86 may be parallel to the drive shaft 22. Also shown in cross-sectional view at the first end 64 are the first leaf 44, the first spring 66, and the first spring groove 54. Similarly, shown at the second end 64 is the second leaf 45, the second spring 47, and the second spring groove 55. On opposite sides of the central gas director 62 are a first central lumen 40 and a second central lumen 41. As also shown in this embodiment, rear cover 16 further includes a feed gas channel 68, a second gas channel 114, a third gas channel 116, and a fourth gas channel 118. Also shown in cross-sectional view are certain elements of the bushing 48, including a first gas directing orifice 72, a second gas directing orifice 74, and a third gas directing orifice 76.

As shown in fig. 9, when the regulator 18 is set to the forward high power position 85, pressurized air or charge gas is directed through the charge gas passage 68, through the charge gas orifices 70, into the central portion 27, and more specifically, into the first central cavity 40. The pressurized gas is contained or directed in the first central cavity 40 between the central gas guide 62 and the radially inner surface 78 of the bushing 48 and then travels out of the regulator 18 through the first gas guide orifice 72 into the second gas passage 114 of the rear cover 16 from where the gas is directed to the air motor 32 of the power tool 10. The flow of feed gas in fig. 9 is shown by arrow a. After the charge gas has been directed to the motor 32 of the power tool 10 and power the power tool 10, exhaust gas from the motor 32 may be directed to the second gas passage 116 of the rear cover 16, through the second gas directing apertures 74 and into the second central cavity 41. The exhaust gas may then be directed between the central gas guide 62 and the radially inner surface 78 of the liner 48 until directed outwardly through the third gas guide aperture 76 into the fourth gas passage 118 of the aft cover 16. As described with respect to fig. 10, the exhaust gas may then pass through the first air passage slot 36 and ultimately be released from the power tool via the exhaust gas passage 11. The flow of exhaust gas in fig. 9 is shown by arrows B.

As can be seen in fig. 9, the first and second vanes 44, 45 seal against the radially inner surface 78 of the bushing 48 and prevent gas from flowing from the first central chamber 40 into the second central chamber 41. Instead, the gas flow is directed out of the first gas directing apertures 72 as feed gas (in the arrangement of fig. 9) and then out of the third gas directing apertures 76 as exhaust gas. The seal resulting from the radial bias of the vanes 44 and 45 outwardly against the relatively smooth and uniform radially inner surface 78 of the liner 48 and, in some embodiments, the resiliency resulting from the radial bias provides an efficient seal to prevent gas flow across the interface of the first end 64 or the second end 66 of the central gas director 62 and the radially inner surface 78 of the liner 48. In addition, the first and second O- rings 38 and 39 serve to prevent gas from flowing out of the first and second central chambers 40 and 41 in the axial direction.

In some embodiments, the regulator 18 is positioned inside the rear cover 16 without the use of a bushing. In such embodiments, the vanes 44 and 45 still function to provide an efficient seal, preventing gas flow across the interface of the first end 64 or the second end 66 of the central gas director 62 and the inner radial surface 126 of the aft cover 16. In these embodiments, first and second O- rings 38, 39 are used to prevent gas from flowing out of first and second central cavities 40, 41 in an axial direction.

Utilizing certain embodiments of the bushing 48 provides manufacturing and assembly advantages because the various apertures in the bushing 48 may be easily and accurately milled or formed. In some embodiments, the rear cover 16 may comprise cast aluminum, the manufacture of which may result in some imprecision in the fit between the inner radial surface 126 and a regulator without the configurations and elements of the present disclosure. The use of a bushing allows for a more simplified back cover design and manufacturing process, as well as greater casting tolerances in back cover 16, while still providing precise airflow aperture sizes and locations in the bushing. The use of a bushing may also provide a more uniform internal shape, surface consistency, and circumference than may be provided by embodiments used on a cast back cover that matches a regulator without a bushing.

Fig. 10 illustrates an oblique front internal cross-sectional view of the end cap 16 and the regulator 18 along line DD of fig. 8. Also shown in fig. 10 are a first shoulder 88 and a second shoulder 90 of the front end 28 of the regulator 18. The first and second shoulders 88, 90 are arcuate partial circumferential shoulders that extend partially along the radial periphery of the forward end 28 of the adjuster 18. Radially inward of first shoulder 88 and second shoulder 90 is an inner seal shoulder 98. Extending partially circumferentially between the internal sealing shoulder 98 and the first and second shoulders 88, 90 are the first and second air passage slots 36, 37, respectively, which define the first and second discharge passages 92, 94, respectively. The first shoulder 88 extends along the periphery of the regulator 18 between the first shoulder openings 102a and 102 b. The second shoulder 90 extends along the periphery of the regulator 18 between the first shoulder openings 104a and 104 b. In fig. 10, the regulator 18 is positioned at the forward high power position 85. When the assembly of fig. 9 is assembled to the drive body 14, the axial surfaces of the first and second shoulders 88, 90 and the internal sealing shoulder 98 mate with the gasket 17, completing the definition of the sealing air passage along the first and second air passage grooves 36, 37, respectively.

Fig. 10 shows the first shoulder opening 102a fully aligned with the fifth gas introduction orifice 110 and the first shoulder opening 102b fully aligned with the fourth gas introduction orifice 108. In the regulator arrangement of fig. 10, exhaust gas from the motor 32 may be directed to the second central chamber 41 (as described with respect to fig. 9), and then to the fourth gas passage 118. From the fourth gas passage 118, the exhaust gas may be directed into and through the first air passage slot 36 through the fourth gas guide orifice 108 (as shown in fig. 10), out of the first shoulder opening 102a, through the fifth gas guide orifice 110 and into the fifth gas passage 120, and from there to the exhaust gas passage 11. As described in connection with FIG. 10, the exhaust gas flow through the first air passage slot 36 is shown by arrows C. (when the regulator 18 is disposed in the reverse positions 82 and 83, the flow of exhaust gas is from the motor 32 to the second gas passage 114, through the first gas directing orifice 72, through the first central cavity 40, through the third gas directing orifice 76, through the fourth gas passage 118, through the fourth gas directing orifice 108, through the second air passage slot, through the sixth gas directing orifice 112, and out of the sixth gas passage 122 to the exhaust gas passageway 11. thus, depending on whether the regulator 18 is disposed in the forward or reverse position, the flow of feed gas and exhaust gas is mirrored in the central portion 27 and the front end 28.

In certain embodiments, the adjuster may be configured in conjunction with the bushing such that no vane overlaps any of the apertures of the central portion 27 at any of the preset positions (such as the exemplary position shown in fig. 15). Further, in some embodiments, the area of the feed gas orifice 70 is less than the area of the first or second gas introduction orifices 72, 74. In some embodiments, the area of the third gas introduction orifice 76 is less than the area of the first or second gas introduction orifices 72, 74.

While a typical regulator can adjust the amount of pressurized gas or liquid flowing through the regulator, most of these are single-use systems that merely adjust the amount of pressurized gas or liquid flowing. In this case, a second device, system or switch is necessary to switch the operation of the terminal device from the forward operation to the reverse operation. Embodiments of the present invention address this inefficiency and accomplish it in a novel manner. By simple rotation of the regulator 18, the operator simultaneously changes the direction of operation (from reverse to forward or vice versa), but also adjusts the amount of pressurized gas or liquid flowing through the regulator by the same simple rotational action.

Fig. 10 also shows a stop receiver segment 100 as shown in the partial view in fig. 16.

Fig. 17a, 17b, 17c and 17d show the flow of feed gas and exhaust gas directed via the regulator 18 at forward high power (fig. 17a and 17 b) and at forward low power (fig. 17c and 17 d). When the regulator 18 is moved to the reverse setting, the flow of feed gas and exhaust gas is readily seen for the reverse high power and reverse low power settings, and the gas flow is mirrored in fig. 17a, 17b, 17c and 17 d. Fig. 17a-17d illustrate a regulator assembly according to an embodiment of the present invention, wherein no bushing is included between the rear cover 16 (or housing) and the regulator 18.

FIG. 11 illustrates an interior elevation view of a regulator with a back cover in cross-sectional view in accordance with at least one embodiment.

FIG. 13 illustrates an angled rear view of the adjuster 18 and bushing 48 in accordance with at least one embodiment. The regulator 18 is positioned radially inside the bushing 48. Shown are a first gas directing aperture 72, a second gas directing aperture 73, and a third gas directing aperture 76, each of which extends from a radially outer surface 79 of the liner 48, through the liner 48, and through a radially inner surface 78 of the liner 48. In the embodiment of fig. 13, the bushing 48 comprises an annular ring having a radially inner surface 78, an aft bushing surface 136, and a forward bushing surface 138, and an axial length 106 extending parallel to the axis 86. Fig. 13 and 14 also show fourth, fifth, and sixth gas introduction apertures 108, 110, and 112 located along the periphery of the front bushing surface 138 and extending through the bushing 48. In some embodiments, the fourth, fifth, and sixth gas introduction apertures 108, 110, 112 may be centrally located along the axial length of the liner 48, rather than on the perimeter of the forward liner surface 138.

Bushing 48 may be formed of bronze or other material. The feed gas orifice 70, the first gas directing orifice 72, the second gas directing orifice 74, and the third gas directing orifice 76 are generally centrally located along the axial length 106 and from the aft liner surface 136. In the embodiment of fig. 13, the feed gas orifice 70, the first gas directing orifice 72, the second gas directing orifice 74, and the third gas directing orifice 76 are generally positioned on a plane perpendicular to the axis 86. The aft bushing surface 136 and the forward bushing surface 138 may each be formed on a plane perpendicular to the axis 86. The fourth, fifth, and sixth gas introduction apertures 108, 110, and 112 may also be generally positioned on a separate plane perpendicular to the axis 86 and may be positioned on the forward bushing surface 138.

FIG. 15 illustrates an enlarged rear view of the power tool and regulator of FIG. 1 in accordance with at least one embodiment. In the illustrated embodiment, the adjuster 18 is rotatable about the axis 86 to align with any one of four positions: reverse high 82, reverse low 83, forward low 84, and forward high 85. The detent system shown in fig. 16 may be used to provide tactile or haptic feedback to a user of the power tool as the adjuster 18 is rotated about the axis 86. In the illustrated embodiment, stop receiver section 100 includes four stop dogs 130a, 130b, 130c and 130d extending radially outward from axis 86. The adjacent stop dogs 130a are a first stop shoulder 132 and a second stop shoulder 134. The first stop shoulder 132 is a smaller radial distance from the axis 86 than the second stop shoulder 134. When the adjuster 18 is positioned in the forward high 85 position, the stop pin 56 extends into the stop block 130a and the first stop shoulder 132 prevents the adjuster 18 from rotating past the position of the stop block 130a in the direction C of fig. 15. The second stop shoulder 134 has the following height and shape: the height and shape facilitates the positive retraction of the stop pin 56 against the stop spring 58 and allows the adjuster 18 to rotate in direction D of fig. 16 to allow the adjuster 18 to be positioned to either stop 130b (forward low power position 84), or stop 130c (reverse low power position 84), or stop 130D (reverse high power position 86). Stop dogs 130c and 130d are not shown in fig. 15. The stop block 130d includes a first stop shoulder 132d and a second stop shoulder 134 d. The radial distance of the first stop shoulder 132D from the axis 86 is less than the radial distance of the second stop shoulder 132D from the axis 86 such that the first stop shoulder 132D prevents the regulator 18 from rotating past the position of the stop block 130D in the direction D of fig. 15 (the reverse high power position 86). Depending on the particular embodiment of the present invention, stop receiver segments 100 may be formed in bushing 48 or in back cover 16.

In some embodiments of the present invention, a bushing 48 is included that is positioned between the back cover 16 and the radially inward surface of the regulator 18. In some embodiments, no bushing is used.

Fig. 9 and 17a illustrate the regulator in the forward high power position 85. As can be seen in fig. 9, first end 64 of central gas director 62 is positioned such that it does not impede the flow of feed gas from feed gas passage 68 through feed gas apertures 70 into first central cavity 40, which feed gas is then directed between central gas director 62 and the radially inner surface of liner 48 to first gas directing apertures 72 into cavity second gas passage 114 of rear cover 16, from which cavity second gas passage 114 it is directed to motor 32 in the following manner: facilitating rotation of the motor 32 at high speed in the forward direction. When the central gas director 62 is positioned as shown in fig. 9, the vanes 44 and 45 are spring biased against the radially inner surface of the bushing 48 to prevent feed gas from leaking from the first central chamber 40 to the second central chamber 41. Set of arrows a shows the flow of feed gas through first central chamber 40. After the feed gas has been passed through the motor 32, the gas, now exhaust gas, is returned to the rear cover 16, as described earlier.

As can be seen in the illustration of fig. 9, in the embodiment of fig. 9 the feed gas is guided into the first central chamber 40 on the side of the central gas guide 62, while at the same rotational position of the regulator 18 the exhaust gas is guided through the second central chamber 41 eventually reaching the exhaust channel 11. It can also be seen that in this rotational position of the regulator 18, the charge gas orifice 70 and the first gas directing orifice 72 are completely unblocked by the first end 64 and the second end 66 of the central gas director 62, respectively, thus allowing high power flow of charge gas through the regulator 38 to the motor 32.

In fig. 17c, the regulator 18 is illustrated in a forward low power 84 setting, with feed gas and exhaust gas flow similar to that of fig. 9, but it should be noted that the first end 64 of the central gas director 62 partially obstructs feed gas orifices 70, thus partially obstructing feed gas flow into the first central cavity 40 and ultimately to the motor 32. By thus impeding the flow of charge gas at the charge gas orifice 70, a reduced air flow is provided to the motor 32, resulting in the power tool 10 operating at low power. When the regulator 18 is adjusted and set at the reverse high power 82, the position of the central gas director 62 will be a mirror image of that in fig. 9, but the feed air entering the second central cavity 41 and exiting the second gas directing orifice 74 is directed to the motor 32, now in reverse flow, causing the motor 32 to rotate in the reverse direction. Because first end 64 of central gas director 62 is positioned such that it does not impede the flow of feed gas from feed gas channel 68 through feed gas orifices 70 into second central cavity 41 when reverse high power 82 is provided, full pressure air is provided to motor 32. Similarly, at the reverse low power 83, the first end 64 of the central gas director 62 partially obstructs the feed gas apertures 70 and, thus, partially obstructs gas flow into the second central cavity 41 and powers the motor 32 at a low power.

The feed gas stream is shown at E in fig. 17a and G in fig. 17 c. The exhaust gas flow is shown at F in fig. 17b and at H in fig. 17 d.

Embodiments of the present invention include novel systems that utilize all aspects of the components of the regulator 18. First, the rear end 26 of the adjuster 18 includes a grip 34 and facilitates the operator in rotating the adjuster 18 and visually indicating the direction and power setting of the adjuster 18 according to the embodiment of FIG. 15. The central portion 27 provides two important functions. It controls the flow of feed gas to a reverse or forward gas channel operatively connected to the motor 32, and also receives exhaust gas from the motor 32 and redirects it to a gas conduit or channel (in some embodiments, the fourth gas channel 118) that directs the exhaust gas (via the front end 28) to the final exhaust gas passageway 11. Third, the front end 28 of the regulator 18 communicates exhaust gas from a gas conduit or passage (such as the fourth gas passage 118) in communication with the central portion 27 through exhaust passages (such as 92 and 94), to gas passages (e.g., 120 and 122), and ultimately to the exhaust gas passageway 11. Fig. 22 illustrates a top cross-sectional view across line EE of fig. 2. In some embodiments, the gas channels 120 and 122 of the rear cover 16 are directly connected to the exhaust gas passage 11, such as shown in fig. 22, where the gas channel 120 is directly connected to the exhaust gas passage 11a and the exhaust gas flow (shown at H) from the gas channel 120 flows to the exhaust gas passage 11a (which may be integral with the exhaust gas passage 11), and the gas channel 122 is directly connected to the exhaust gas passage 11b and the exhaust gas flow (shown at J) from the gas channel 122 flows to the exhaust gas passage 11b (which may also be integral with the exhaust gas passage 11).

Certain advantages are obtained in various embodiments of the invention. In certain embodiments, it is desirable to provide a user-friendly degree of rotation of the regulator 18 from one extreme of the preset range of rotation to the opposite end of rotation, while still facilitating various design airflows for particular embodiments. In the embodiment of fig. 15, four separate preset adjuster positions are shown. Furthermore, it is advantageous to minimize the pressure loss of the feed gas as it travels through the sequential orifices, chambers. The size and location of the orifices 70, 72, 74, and 76 is important and particularly related to the cross-sectional profile of the central lumen 40 or 41 and the size of the first and second ends 64 and 64 of the central gas guide 68.

FIG. 19 illustrates an embodiment of an exemplary blade according to some embodiments. Shown are the notches 50 and 51, the vane sealing surface 140, the vane end wall and the spring seat slot 142. In some embodiments, it is advantageous, such as shown, that the vanes are tapered such that a radially outer portion of the vane (proximate the vane sealing surface) has a greater length 152 than a radially inner portion 154 of the vane (proximate the spring seat slot). This conical shape accommodates the free movement of the blades in the radial direction and further facilitates the assembly of the related components.

FIG. 20 illustrates a cross-sectional view of an exemplary blade according to certain embodiments. Shown are the vane 44b and the vane sealing surface 140 a. As can be seen, the vane sealing surface 140a is not planar in cross-section but is arcuate with the greater radius section of the arc being disposed to bear against the radially inner surface 78 of the bushing 48 or the radially inner surface of the aft cover 16. In other embodiments, the vane sealing surface 140a can be triangular in cross-section.

In certain embodiments, it has been preferred to provide a high power setting of the tool 10, powered by a 90 psi source of pressurized air. It is also sometimes preferable to provide a low power setting that produces a low power torque as measured by the power tool 10 output drive that is about 65% to 80% of the torque of the full power setting, and more preferably about 75% plus or minus 8% of the full power torque. It is also sometimes preferred to provide a low power setting that produces a low power free speed of the tool output drive that is about 65% to 80% of the free speed of the full power setting, and more preferably about 75% plus or minus 8% of the full power free speed. It has been found that if first end 64 at the low power setting is sized and the degree of rotation of regulator 18 at the low power setting is set such that first end 64 blocks approximately 84% of the area of material orifices 72, a speed reduction and torque reduction of approximately 25% of the normal full power mode will be achieved. Thus, in some embodiments, it is preferred that first end 64 block from 80% to 90% of the area of material apertures 72, and more preferably block about 84% plus or minus 2% of the area of material apertures 72. Further, in some embodiments, it has been found that the relative circumferential widths (or lengths) of the first and second ends 64, 66 are from 2/1 to 4/1 in ratio, and more preferably are generally about 3/1 in ratio. It has also been found that with the width ratios mentioned above and the desired power reduction, the regulator 18 rotates about 35 degrees from top dead center (as shown by the center of the orifice 76) at full power setting and about 9.3 degrees (plus or minus 2 degrees) from top dead center in the reduced power mode. Further, it has been found that to provide preferred performance in certain embodiments of the present invention, the center of each of the orifices 72 and 74 is generally displaced in opposite directions by about 55 degrees from the center of the third gas introduction orifice 76. In certain embodiments, it has been found that to achieve a 20% reduction in power or free velocity, it is preferred to have the first end 64 block about 80% of the area of the feed gas orifice 70. To facilitate achieving the desired pressure drop across the feed gas flow system, it has been found that the ratio of the area of feed gas orifices 70 to the area of orifices 72 and 74 is typically on the order of about 11 to 16 or approximately about 11 to 16.

In some embodiments, it is generally desirable that the pressure drop, such as from the feed gas channel 68 until the feed gas enters the second gas channel 114 or the third gas channel 116 (depending on forward or reverse operation) is minimal and fairly linear and/or consistent. It has been found that for a 90 psi feed gas at full power operation, a reduction of about 1.5 psi occurs over the length from the feed gas coupler 13 to the end cap 16, a reduction of typically about 1.3 psi occurs from the end cap 16 through the feed gas channel and into the central cavity 40 or 41, and a reduction of typically about 1.6 psi occurs during the flow of gas from the central cavity 40 or 41 through the first or second gas directing apertures 72 or 74, with a total pressure reduction from the feed gas coupler 13 through the first or second gas directing apertures 72 or 74 of about 4 to 5.5 psi.

In some embodiments, bushing 48 may be press fit into back cover 16 or the housing. In some embodiments, including those in which bushing 48 comprises aluminized bronze and backing cap 16 comprises cast aluminum, it is preferred that the outer diameter of bushing 48 be about 0.045 mm greater than the inner diameter of the cavity in backing cap 16 into which the bushing is to be press fit (for a bushing having an outer diameter of about 73 mm and a backing cap cavity having an inner diameter of about 71.955 mm, such that the outer diameter of the bushing is approximately 1.015 times (plus or minus 0.011 times) the inner diameter of the backing cap cavity.

The configuration of the embodiments of the present invention provides economy of manufacture. For example, bushing 48 may be formed by cutting a tube composed of a suitable brass alloy and having a designed general target inner and outer diameter for bushing 48. The surfaces of the rear bushing surfaces 134 and 136 are formed and prepared, and various apertures of the bushing are machined. After those operations are completed, the radially inner surface 78 of the bushing 48 may be machined and surface finished, and the radially outer surface 79 of the bushing 48 may also be machined and surface finished. Because these inner and outer machining steps may produce burrs associated with the orifice, the orifice opening may be chamfered on a radially inner portion of the orifice opening, on a radially outer portion of the orifice opening, or on both the radially inner and outer portions of the orifice opening after the machining and surface polishing steps.

The material selection criteria for the bushing may include the following considerations or objectives: the material does not rust, lead is not present in the material, the material has high hardness, and the material can be economically machined. In some embodiments, it is preferred to use a lead-free aluminized bronze material as the liner, which has a tensile strength of between 65000 psi and 105000 psi, and more preferably a tensile strength of generally about 85000 psi plus or minus 10000 psi. In some embodiments, it is also preferred to use an aluminized bronze material having a hardness generally about B85. In some embodiments, the liner material may be an aluminized bronze product C95400 having ASTM B505 and in some embodiments B505M. In some embodiments, the housing or back cover 16 or other housing of the power tool 10 may comprise cast aluminum. It may be important in certain embodiments that the tool or regulator assembly have sufficient drop safety for harsh uses. By using the aluminized bronze material described above or other material with similar strength and hardness characteristics, the regulator is preferably protected from tool drop so that if the tool is dropped, the bushing has sufficient strength that it will not become out of round and the integrity of the regulator system is maintained. In some embodiments, the liner material may have a tensile strength and hardness that exceeds the tensile strength and hardness of the back cover or shell. Additionally, the bushing may be press fit into the back cover or housing. The increased tensile strength and/or hardness of the bushing material serves to protect the integrity of the bushing shape during the press-fit operation so that the machined circular shape of the bushing remains intact during assembly. The combination of a strong bronze bushing with an aluminum back cover provides advantages including: the strength required (in the bushing to maintain the shape of the bushing and a tight seal with the blade), and the weight savings and economy of an aluminum aft cover or shell, where less strength may be offset by the weight savings and/or economy.

In certain embodiments, it is preferred that the radially inner surface 78 of the bushing 48 be machined and polished to a surface roughness of 20 to 62 microinches, or more preferably, generally about 32 plus or minus 8 microinches. This reduced level of surface roughness provides an efficient seal with the blade and reduces wear on the blade. In certain embodiments, the blades may comprise plastic materials, thermoplastic composites, materials with reduced or low friction properties, metals, Teflon (Teflon) components, or other materials. In certain embodiments, the blades may comprise a material having a hardness less than the hardness of the radially inner surface 78 of the bushing 48. It has been found that in certain embodiments, a material having the characteristics of LNP lubricant material compound SX93441D may facilitate formation of a blade. The beneficial results are: the material of the blades is minimally affected by moisture, organic matter and other contaminants that may be in the gases of the system, they have increased wear resistance, they do not rust, they do not present adverse electrochemical complications with adjacent materials, and they resist warping upon cooling or curing if molded. In some embodiments, the fit between the vanes and the vane slots in the regulator is very tight (to reduce or prevent gas leakage through the loose fit of these components). Thus, it is important that the material of the blade, if a moulding material, is a very stable material and has a low moisture absorption and a high resistance to warping or shrinkage after being moulded. It has been found that SX93441D provides preferred properties as a vane material in certain embodiments.

In some embodiments, a biased vane structure may not be included, and instead, the diameter of the radially outer surface 79 of the bushing 48 may increase in axial length between the first and second O-rings.

In some embodiments, more than two O-rings may be utilized in conjunction with the regulator, such as when it is desired that individual axial regions of the regulator be isolated from gas flow from adjacent axial regions.

In some embodiments, the regulator of the present invention may be configured to provide only control of the feed gas pressure or volume by rotation of the regulator. In some embodiments, the adjuster may be configured to provide only directional control of the motor 32 through rotation of the adjuster.

While the invention has been described with reference to specific embodiments, those skilled in the art will appreciate that various changes can be made without departing from the spirit or scope of the invention. Accordingly, the disclosure of the embodiments is intended to be illustrative of the scope of the invention and is not intended to be limiting. It is intended that the scope of the invention shall be limited only to the extent required by the appended claims. It will be readily apparent to those of ordinary skill in the art that the systems and methods discussed herein may be implemented in a variety of embodiments, and the foregoing discussion of certain of these embodiments does not necessarily represent a complete description of all possible embodiments. Rather, the detailed description of the drawings, as well as the drawings themselves, disclose at least one embodiment, and may disclose alternative embodiments.