One-way clutch for use in a no-back clutch design

Abstract

An actuator is provided and includes first and second shafts, a friction plate affixed to the second shaft, a one-way clutch that includes an inner diameter portion affixed to the first shaft, an outer diameter portion and a one-way clutch portion interposed between the inner and output diameter portions and a bearing. The bearing is disposed such that a compressive load path is formed from the first shaft, through the bearing and the outer diameter portion and to the friction plate and the second shaft. The one-way clutch portion is configured for free-wheeling during forward rotation of the first shaft that permits forward rotation transmission to the second shaft and for jamming during reverse rotation of the first shaft to create a drag event on the friction plate that inhibits reverse rotation transmission to the second shaft.

Claims

1. An actuator, comprising: an input shaft comprising a central shaft portion and a screw flange extending radially outwardly from the central shaft portion; an output shaft; a friction plate affixed to the output shaft; a one-way clutch comprising an inner diameter portion affixed to the central shaft portion, an outer diameter portion and a one-way clutch portion interposed between the inner and outer diameter portions; and a bearing disposed between the screw flange and the outer diameter portion such that a compressive load path is formed from the screw flange, through the bearing and the outer diameter portion and to the friction plate and the second shaft, the one-way clutch portion interposed between the inner and outer diameter portions being configured for free-wheeling during forward rotation of the first shaft that permits forward rotation transmission to the second shaft and for jamming during reverse rotation of the first shaft to create a drag event on the friction plate that inhibits reverse rotation transmission to the second shaft.

2. The actuator according to claim 1, wherein the one-way clutch portion comprises a sprag clutch.

3. The actuator according to claim 1, wherein the bearing comprises a thrust bearing.

4. The actuator according to claim 1, wherein the bearing comprises a needle roller bearing.

5. The actuator according to claim 1, wherein the bearing comprises a ball bearing.

6. The actuator according to claim 1, further comprising a plate element interposed between the outer diameter portion and the friction plate.

7. An actuator, comprising: an input shaft comprising a central shaft portion and a screw flange extending radially outwardly from the central shaft portion; an output shaft; a friction plate affixed to the output shaft; a one-way clutch comprising an inner diameter portion affixed to the central shaft portion, an outer diameter portion and a one-way clutch portion interposed between the inner and output diameter portions; and a bearing disposed between the screw flange and the outer diameter portion such that a compressive load path is formed from the screw flange, through the bearing and the outer diameter portion and to the friction plate and the output shaft, the one-way clutch portion being configured for free-wheeling during forward rotation of the input shaft to thereby permit rotation of the input shaft in the forward direction to be transmitted to the output shaft and for jamming during reverse rotation of the input shaft to create a drag event on the friction plate to thereby inhibit rotation of the input shaft in the reverse direction to be transmitted to the output shaft.

8. The actuator according to claim 7, wherein the one-way clutch portion comprises a sprag clutch.

9. The actuator according to claim 7, wherein the bearing comprises one or more of a thrust bearing, a needle roller bearing and a ball bearing.

10. The actuator according to claim 7, further comprising a plate element interposed between the outer diameter portion and the friction plate.

11. An actuator of an electric powered nacelle door opening system (PDOS) comprising a nacelle door of an aircraft engine, the actuator comprising: an input shaft comprising a central shaft portion and a screw flange extending radially outwardly from the central shaft portion; an output shaft coupled to the nacelle door; a friction plate affixed to the output shaft; a one-way clutch comprising an inner diameter portion affixed to the central shaft portion, an outer diameter portion and a one-way clutch portion interposed between the inner and output diameter portions; and a bearing disposed between the screw flange and the outer diameter portion such that a compressive load path is formed from the screw flange, through the bearing and the outer diameter portion and to the friction plate and the output shaft, the one-way clutch portion being configured for free-wheeling during forward rotation of the input shaft to thereby permit rotation of the input shaft in the forward direction to be transmitted to the output shaft and for jamming during reverse rotation of the input shaft to create a drag event on the friction plate to thereby inhibit rotation of the input shaft in the reverse direction to be transmitted to the output shaft.

12. The actuator according to claim 11, wherein the one-way clutch portion comprises a sprag clutch.

13. The actuator according to claim 11, wherein the bearing comprises one or more of a thrust bearing, a needle roller bearing and a ball bearing.

14. The actuator according to claim 11, further comprising a plate element interposed between the outer diameter portion and the friction plate.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The subject matter, which is regarded as the disclosure, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features and advantages of the disclosure are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

(2) FIG. 1 is a side view of an electric powered nacelle door operating system (PDOS) in accordance with embodiments;

(3) FIG. 2 is a schematic illustration of a one-way clutch based on a no-back design in accordance with embodiments;

(4) FIG. 3 is a schematic illustration of an operation of the one-way clutch of FIG. 2 during forward rotation; and

(5) FIG. 4 is a schematic illustration of an operation of the one-way clutch of FIG. 2 during reverse rotation.

(6) These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings.

DETAILED DESCRIPTION

(7) As will be described below, a one-way clutch for use in a no-back clutch design is provided. The one-way clutch can be used in place of a pawl and ratchet mechanism to drag on a friction disk when reverse rotation occurs.

(8) With reference to FIG. 1, an actuator 101 is provided for use in an electric powered nacelle door opening system (PDOS) 102, which includes a nacelle door 103 of an aircraft engine. The actuator 101 includes a first or input shaft 110 (hereinafter referred to as an “input shaft 110”), a second or output shaft 120 (hereinafter referred to as an “output shaft 120”) that is coupled to the nacelle door 103, a friction plate 130 that is affixed to the output shaft 120, a one-way clutch 140 and a bearing 150.

(9) With reference to FIGS. 2-4, further details of the actuator 101 of FIG. 1 will be described. As shown in FIGS. 2-4, the input shaft 110 includes a central shaft portion 111 and a screw flange 112 extending radially outwardly from the central shaft portion 111. The central shaft portion 111 extends along a longitudinal axis that is defined in parallel with an actuator or rotational axis such that the input shaft 110 is rotatable in forward and reverse directions about the actuator axis to drive movements of the nacelle door 103 (see FIG. 1). The one-way clutch 140 includes an inner diameter portion 141 that is affixed to the central shaft portion 111 of the input shaft 110, an outer diameter portion 142 and a one-way clutch portion 143 that is radially interposed between the inner diameter portion 141 and the output diameter portion 142. A plate element 160 can be axially interposed between the outer diameter portion 142 of the one-way clutch 140 and the friction plate 130.

(10) The bearing 150 is disposed such that a compressive load path (see FIGS. 1 and 2) is formed and defined to extend from the screw flange 112 of the input shaft 110, through the bearing 150, through the outer diameter portion 142 of the one-way clutch 140 and through the plate element 160 and to the friction plate 130 and the output shaft 120. The compressive load path refers to a pathway through the actuator 101 by which compressive loads, which are always present during operational conditions of the actuator 101, are transmitted and absorbed. The compressive loads result in back-driving torques being generated in the actuator 101.

(11) In accordance with embodiments, the one-way clutch portion 143 can include or be provided as a sprag clutch 144 and the bearing 150 can include or be provided as one or more of one or more of a thrust, needle roller and a ball bearing 151.

(12) As shown in FIGS. 3 and 4, the one-way clutch portion 143 is disposed and configured for free-wheeling operation during forward rotation of the input shaft 110 (see FIG. 3) and for jamming operation during reverse rotation of the input shaft 110 (see FIG. 4) that may be caused by the back-driving torques generated by the compressive loads. The free-wheeling operation of the one-way clutch portion 143 serves to permit rotation of the input shaft 110 in the forward direction to be transmitted to the output shaft 120. By contrast, the jamming operation of the one-way clutch portion 143 serves to create a drag event on the friction plate 130 to thereby inhibit rotation of the input shaft 110 in the reverse direction to be transmitted to the output shaft.

(13) Technical effects and benefits of the one-way clutch for use in the no-back clutch design results in a compact configuration with a reduced number of components, reduced weight and reduced costs.

(14) While the disclosure is provided in detail in connection with only a limited number of embodiments, it should be readily understood that the disclosure is not limited to such disclosed embodiments. Rather, the disclosure can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the disclosure. Additionally, while various embodiments of the disclosure have been described, it is to be understood that the exemplary embodiment(s) may include only some of the described exemplary aspects. Accordingly, the disclosure is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.