Speed reducer arrangement for a line retraction device

Abstract

A speed reducer arrangement (200) for a line retraction device (100), including at least one lug (4) fixed on a surface of a rotatable hub (2) and configured to rotate along with the hub (2); at least one brake shoe (5) having at least one groove (8) extending therethrough and configured to at least partially receive the at least one lug (4), such that, as the hub (2) rotates, the at least one brake shoe (5) is configured to slidably move along the at least one groove (8) from an inactivated position, wherein the at least one brake shoe (5) is located nearest the center of the hub (2) to an activated position, wherein the at least one brake shoe (5) contacts at least one contact surface of the line retraction device (100) to thereby slow the rotation of the hub (2); and at least one biasing member (6) configured to urge the at at least one brake shoe (5) towards the inactivated position.

Claims

1. A speed reducer arrangement for a line retraction device having a hub configured to rotate about a center axis and having a line associated therewith, the line including a first end directly or indirectly attached to the hub and a second end opposite the first end, and at least one retraction member biasing the hub in a first rotational direction of the hub opposite a second rotational direction of the hub, wherein the hub is configured to: (i) retract the line when the hub moves in the first rotational direction; and (ii) release the line when the hub moves in the second rotational direction, wherein the speed reducer arrangement comprises: at least one lug fixed on a surface of the hub and configured to rotate along with the hub; at least one brake shoe having at least one groove extending therethrough and configured to at least partially receive the at least one lug, such that, as the hub rotates, the at least one brake shoe is configured to slidably move along the at least one groove from an inactivated position, wherein the at least one brake shoe is located nearest the center of the hub, to an activated position, wherein the at least one brake shoe contacts at least one contact surface of the line retraction device to thereby slow the rotation of the hub; and at least one biasing member configured to urge the at least one brake shoe towards the inactivated position, wherein the at least one biasing member is attached to and in tension with the at least one brake shoe.

2. The speed reducer arrangement of claim 1, wherein the line retraction device comprises at least one housing at least partially surrounding the hub, and wherein the at least one contact surface comprises at least one surface of the at least one housing.

3. The speed reducer arrangement of claim 1, wherein the at least one groove extends at an angle with respect to a line connecting a center point of the at least one groove and the center axis of the hub.

4. The speed reducer arrangement of claim 3, wherein the angle is an acute angle, and wherein the degree of the acute angle is selected such that the speed at which the at least one brake shoe moves from the inactivated position to the activated position when the hub moves in the second rotational direction is greater than the speed at which the at least one brake shoe moves from the inactivated position to the activated position.

5. The speed reducer arrangement of claim 3, wherein the angle is an acute angle in the range of about 0? to about 60?.

6. The speed reducer arrangement of claim 3, further comprising a plurality of brake shoes radially spaced about the center axis of the hub, wherein the angle for each of the plurality of brake shoes is substantially identical.

7. The speed reducer arrangement of claim 1, wherein the force of engagement between the at least one brake shoe and the at least one contact surface of the line retraction device is proportional to the speed at which the hub is rotating.

8. The speed reducer arrangement of claim 1, further comprising at least one holding groove configured to receive the at least one brake shoe, such that the at least one brake shoe can slide from the inactivated position to the activated position.

9. The speed reducer arrangement of claim 8, further comprising a plurality of holding grooves configured to receive a respective one of a plurality brake shoes, wherein the angle between a line connecting a center point of each of adjacent holding grooves and the center axis of the hub is about 90?.

10. The speed reducer arrangement of claim 8, wherein the radial length of the at least one brake shoe is from about 1 mm to about 5 mm shorter than the radial distance from a bottom edge of the at least one holding groove and the at least one contact surface of the line retraction device.

11. The speed reducer arrangement of claim 1, wherein the at least one biasing member is attached between at least a portion of the at least one brake shoe and at least one of the following: at least a portion of the hub, at least a portion of at least one other brake shoe, or any combination thereof, such that the at least one brake shoe is urged towards the inactivated position.

12. The speed reducer arrangement of claim 1, further comprising a plurality of brake shoes radially spaced about the center axis of the hub, wherein the at least one biasing member comprises a plurality of biasing members, each of which is attached between two of the plurality of brake shoes.

13. The speed reducer arrangement of claim 1, wherein the length of the at least one groove is in the range of about ? to about ? the radial length of the at least one brake shoe.

14. The speed reducer arrangement of claim 1, wherein the at least one lug is fixed to the surface of the hub by at least one attachment member.

15. The speed reducer arrangement of claim 1, wherein the at least one biasing member is at least one spring.

16. A line retraction device, comprising: a hub configured to rotate about a center axis and having a line associated therewith, the line including a first end directly or indirectly attached to the hub and a second end opposite the first end; at least one retraction member biasing the hub in a first rotational direction of the hub opposite a second rotational direction of the hub, wherein the hub is configured to: (i) retract the line when the hub moves in the first rotational direction; and (ii) release the line when the hub moves in the second rotational direction; and a speed reducer arrangement, comprising: (i) at least one lug fixed on a surface of the hub and configured to rotate along with the hub; (ii) at least one brake shoe having at least one groove extending therethrough and configured to at least partially receive the at least one lug, such that, as the hub rotates, the at least one brake shoe is configured to slidably move along the at least one groove from an inactivated position, wherein the at least one brake shoe is located nearest the center of the hub, to an activated position, wherein the at least one brake shoe contacts at least one contact surface of the line retraction device to thereby slow the rotation of the hub; and (iii) at least one biasing member configured to urge the at least one brake shoe towards the inactivated position, wherein the at least one biasing member is attached to and in tension with the at least one brake shoe.

17. The line retraction device of claim 16, further comprising at least one housing at least partially surrounding the hub, and wherein the at least one contact surface comprises at least one surface of the at least one housing.

18. The line retraction device of claim 16, wherein the force of engagement between the at least one brake shoe and the at least one contact surface of the line retraction device is proportional to the speed at which the hub is rotating.

19. The line retraction device of claim 16, wherein the at least one groove extends at an angle with respect to a line connecting a center point of the at least one groove and the center axis of the hub.

20. The speed reducer arrangement of claim 19, wherein the angle is an acute angle, and wherein the degree of the acute angle is selected such that the speed at which the at least one brake shoe moves from the inactivated position to the activated position when the hub moves in the second rotational direction is greater than the speed at which the at least one brake shoe moves from the inactivated position to the activated position.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Some of the advantages and features of the preferred aspects or embodiments of the invention have been summarized herein above. These embodiments, along with other potential aspects or embodiments of the invention, will become apparent to those skilled in the art when referencing the following drawings in conjunction with the detailed descriptions as they relate to the figures.

(2) FIG. 1 is a schematic view of one embodiment of a line retraction device with a speed reducer arrangement in an inactivated position according to the principles of the present invention;

(3) FIG. 2 is a partial enlarged view of a portion of the line retraction device with a speed reducer arrangement of FIG. 1;

(4) FIG. 3 is a schematic view of the line retraction device with a speed reducer arrangement of FIG. 1 in an activated position;

(5) FIG. 4 is a partial enlarged view of the line retraction device with a speed reducer arrangement of FIG. 3;

(6) FIG. 5 is an exploded, perspective view of the line retraction device with a speed reducer arrangement of FIG. 1;

(7) FIG. 6 is an exploded, perspective view of the line retraction device with a speed reducer arrangement of FIG. 1;

(8) FIG. 7 is an exploded, perspective view of the line retraction device with a speed reducer arrangement of FIG. 1;

(9) FIG. 8 is an exploded, perspective view of the line retraction device with a speed reducer arrangement of FIG. 1 illustrating a shaft and a line of the line retraction device;

(10) FIG. 9 is a schematic view of another embodiment of a line retraction device with a speed reducer arrangement in an inactivated position according to the principles of the present invention;

(11) FIG. 10 is a partial enlarged view of a portion of the line retraction device with a speed reducer arrangement of FIG. 9;

(12) FIG. 11 is a schematic view of the line retraction device with a speed reducer arrangement of FIG. 9 in an activated position;

(13) FIG. 12 is a partial enlarged view of the line retraction device with a speed reducer arrangement of FIG. 11; and

(14) FIG. 13 is an exploded, perspective view of the line retraction device with a speed reducer arrangement of FIG. 9 illustrating a shaft and a line of the line retraction device.

DETAILED DESCRIPTION OF THE INVENTION

(15) For purposes of the description hereinafter, the terms end, upper, lower, right, left, vertical, horizontal, top, bottom, lateral, longitudinal and derivatives thereof shall relate to the invention as it is oriented in the drawing figures. However, it is to be understood that the invention may assume various alternative variations and step or stage sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification, are simply exemplary embodiments or aspects of the invention. Hence, specific dimensions and other physical characteristics related to the embodiments or aspects disclosed herein are not to be considered as limiting.

(16) The present invention is directed to a line retraction device 100 and a speed reducer arrangement 200 for such a line retraction device 100, as illustrated in certain preferred and non-limiting embodiments or aspects and in schematic form in FIGS. 1-13. The line retraction device 100 may be in the form of a lanyard, a self-retracting lanyard, and/or a fall protection device.

(17) Accordingly, and in one preferred and non-limiting embodiment or aspect, provided is a speed reducer arrangement 200 for a line retraction device 100. With reference to FIGS. 1, 8, and 13, the line retraction device 100 includes a hub 2 configured to rotate about a center axis (A). The hub 2 includes a winding section 21, and a line 13, such as a cable, a web, an elongated member, or the like, that is wrapped around or wound about the winding section 21. The line 13 is includes a first end directly or indirectly attached to the hub 2 (such as in the groove 30 on the hub 2 (see FIG. 8)) and a second end, opposite the first end, having an attachment member (not shown) for removable attachment to a user, e.g., a harness arrangement worn by the user. In addition, and in one preferred and non-limiting embodiment or aspect, the line retraction device 100 includes at least one retraction member (not shown) biasing the hub in a first rotational direction of the hub 2 opposite a second rotational direction of the hub 2, wherein the hub 2 is configured to: (i) retract the line 13 when the hub 2 moves in the first rotational direction (e.g., the clockwise direction); and (ii) release (or pay out) the line 13 when the hub 2 moves in the second rotational direction (e.g., the counterclockwise direction). When the winding section 21 of the hub 2 is retracting or releasing the line 13, the hub 2 rotates about the shaft 10 (which, in one preferred and non-limiting embodiment or aspect, defines the center axis (A)). It is recognized that, in some embodiments, the shaft 10 rotates with the hub 2, and in other embodiments, the hub 2 rotates around the shaft 10, i.e., the shaft 10 is stationary with respect to the rotating hub 2. It will be apparent to those of ordinary skill in the art that any arrangement in reverse or symmetrical adjustment of the inner structure of the line retraction device 100 or the speed reducer arrangement 200 of the present invention may be made to the disclosed embodiments without departing from the spirit and scope of the invention, and fall into the protection scope of the invention.

(18) Referring to FIGS. 1-4 and 9-12 and in one preferred and non-limiting embodiment or aspect, the line retraction device 100 includes a housing 1, which includes a generally hollow interior and contains the speed reducer arrangement 200 and other internal components of the line retraction device 100, such as the hub 2. Further, this housing 1 is considered stationary with respect to the moving components of the line retraction device 100. In one preferred and non-limiting embodiment or aspect, the housing 1 includes an internal surface that serves as an at least one contact surface 32. This at least one contact surface 32 may be made from or coated with a frictional material, such as a material with a high coefficient of friction. An anchor 12, which may be made of a line or other connection arrangement, is positioned on the housing 1 for hanging or positioning the line retraction device 100 during use and operation. Further, a handle 11 may be positioned on the housing 1, such that the line retraction device 100 can be easily transported or carried when not in use.

(19) In one preferred and non-limiting embodiment or aspect, the speed reducer arrangement 200 includes at least one lug 4 fixed (such as by at least one attaching member 3) on a surface of the hub 2 and configured to rotate along with the rotatable hub 2, and at least one brake shoe 5 having at least one groove 8 extending therethrough and configured to at least partially receive the at least one lug 4, such that, as the hub 2 rotates, the at least one brake shoe 5 is configured to slidably move along the at least one groove 8 from an inactivated position, wherein the at least one brake shoe 5 is located nearest the center of the hub 2 (e.g., the center axis (A)) (see FIGS. 1, 2, 9, and 10), to an activated position, wherein the at least one brake shoe 5, e.g., a contact edge 35 of the at least one brake shoe 5, contacts the at least one contact surface 32 of the line retraction device 100 to thereby slow the rotation of the hub 2 (see FIGS. 3, 4, 11, and 12). The speed reducer arrangement 200 further includes at least one biasing member 6 configured to urge the at least one brake shoe 5 towards the inactivated position. In this manner, and as the hub 2 rotates (in either the first rotational direction or the second rotational direction), the at least one brake shoe 5 experiences centrifugal force, which, when high enough to overcome the urging force of the at least one biasing biasing member 6, the at least one brake shoe 5 (e.g., the contact edge 35) moves towards and contacts the at least one contact surface 32. Based upon the frictional engagement, the rotation of the hub 2 is slowed, which, in turn, reduces the speed of release or retraction of the line 13.

(20) In one preferred and non-limiting embodiment or aspect, and with reference to FIG. 1, the at least one groove 8 (represented by a line (L1)) extends at angle (B) with respect to a line (L2) connecting a center point (CP1) of the at least one groove 8 and the center axis (A) of the hub. In another preferred and non-limiting embodiment or aspect, the angle (B) is an acute angle, and the degree of the acute angle is selected such that the speed at which the at least one brake shoe 5 moves from the inactivated position to the activated position when the hub 2 moves in the second rotational direction is greater than the speed at which the at least one brake shoe 5 moves from the inactivated position to the activated position. In another preferred and non-limiting embodiment or aspect, the angle (B) is an acute angle in the range of about 0? to about 60?, and in another preferred and non-limiting embodiment or aspect, the angle (B) is in the range of about 15? to about 30?. In another preferred and non-limiting embodiment or aspect, the speed reducer arrangement 200 includes a plurality of brake shoes 5 radially spaced about the center axis (A) of the hub 2, and the angle (B) for each of the plurality of brake shoes 5 is substantially identical. Based upon the angle (B) selected, and in one preferred and non-limiting embodiment or aspect, the force of engagement or contact between the at least one brake shoe 5 and the at least one contact surface 32 of the line retraction device 100 is proportional to the speed at which the hub 2 is rotating. In one preferred and non-limiting embodiment or aspect, the length of the at least one groove 8 is in the range of about ? to about ? the radial length (L5) of the at least one brake shoe 5.

(21) With reference to FIGS. 1-5 and 9-13, and in one preferred and non-limiting embodiment or aspect, the speed reducer arrangement 200 includes at least one holding groove 7 configured to receive the at least one brake shoe 5, such that the at least one brake shoe 5 can slide from the inactivated position to the activated position. In another preferred and non-limiting embodiment or aspect, and as illustrated in FIGS. 3 and 11, the speed reducer arrangement 200 includes a plurality of holding grooves 7 configured to receive a respective one of a plurality brake shoes 5, wherein an angle (C) between a line (L3) connecting a center point (CP2) of each of adjacent holding grooves 7 and a line (L4) connecting the center axis (A) of the hub 2 is about 90?. In another preferred and non-limiting embodiment or aspect, and with reference to FIG. 1, the radial length (L5) of the at least one brake shoe 5 is from about 1 mm to about 5 mm shorter than the radial distance (L6) from a bottom edge 33 of the at least one holding groove 7 and the at least one contact surface 32 of the line retraction device 100. In the preferred and non-limiting embodiment or aspect of FIGS. 9-13, the holding grooves 7 are formed by two adjacent guide members 36. Generally, these holding grooves 7 are sized and shaped so as to at least partially constrain and facilitate the guided movement of the brake shoes 5 from the inactivated position to the activated position.

(22) In one preferred and non-limiting embodiment or aspect, the at least one biasing member 6 is attached between at least a portion of the at least one brake shoe 5 and at least one of the following: at least a portion of the hub 2, at least a portion of at least one other brake shoe 5, or any combination thereof, such that the at least one brake shoe 5 is urged towards the inactivated position. In one preferred and non-limiting embodiment or aspect, the at least one biasing member 6 is in the form of at least one spring 34. As illustrated in the embodiment of FIGS. 1-8, and in one preferred and non-limiting embodiment or aspect, the at least one biasing member 6, e.g., a spring 34, is attached between at least one brake shoe 5 and a surface of the hub 2. As illustrated in the embodiment of FIGS. 9-13, and in one preferred and non-limiting embodiment or aspect, the at least one biasing member 6, e.g., a spring 34, is attached between two (preferably adjacent) brake shoes 5.

(23) With reference to FIGS. 1, 2, 5, 6, 7 and 8, and in one preferred and non-limiting embodiment or aspect, the speed reducer arrangement includes four holding grooves 7 arranged on the radial direction of the hub 2, where these holding grooves 7 are formed by the guide members 36 in the embodiment of FIGS. 9-13. As discussed above, the angle (C) between the connection line (L3) and line (L4) connecting with the center axis (A) may be 90?, which provides an evenly spaced layout on the circumference of the hub 2. Such holding grooves 7 also provide improved positioning of the brake shoes 5. In one preferred and non-limiting embodiment or aspect, the lugs 4 have an elongated, linear shape with screw holes 37 (see FIGS. 6 and 13) at both ends, which can be fixed to the hub 2 by screws 3. In a further preferred and non-limiting embodiment or aspect, one end of the at least one biasing member 6 is attached to the hub 2, and the other end of the at least one biasing member 6 is attached to a surface of the at least one brake shoe 5 on a non-axis side by the division of the extension line of the at least one groove 8. Therefore, the radial force towards the central axis (A), caused by the at least one biasing member 6, urges the at least one brake shoe 5 toward the central axis (A), and functions to reset the at least one brake shoe 5 to the inactivated position.

(24) As discussed above, and as illustrated in FIGS. 9-13 in one preferred and non-limiting embodiment or aspect, the speed reducer arrangement 200 includes four brake shoes 5. However, in this embodiment or aspect, the at least one biasing member 6 (e.g., a spring 34) is attached between adjacent ends of adjacent brake shoes 5. Accordingly, in this embodiment or aspect, the members 6 are not attached to the hub 2, and are simple to install and maintain. When both the left and right end of a brake shoe 5 is affected by two members 6 on the circumference, the resultant force produced by members 6 is towards the central axis (A) of the hub 2, thus effectively resetting the brake shoes 5 to the inactivated position. Further, and as discussed above, the embodiment of FIGS. 9-13 include guide members 36 that at least partially bound and define the holding grooves 7.

(25) As discussed above, when the at least one brake shoe 5 is positioned nearest to the central axis (A), e.g, the shaft 10, in the inactivated position, such as under the urging of the at least one biasing member 6, a radial gap exists between the at least one brake shoe 5 and the at least one contact surface 32 of the housing 1 of the line retraction device 100. In one preferred and non-limiting embodiment or aspect, the gap is in the range of between about 1 mm to about 5 mm. In one preferred and non-limiting embodiment or aspect, the at least one groove is an elongated groove extending through the at least one brake shoe 5. Further, in one preferred and non-limiting embodiment or aspect, the line (L2) connecting the center point (CP) of the at least one groove 8 and the central axis (A) (e.g., the shaft 10) is set as a start edge and the length direction (L1) of the at least one groove 8 is set as a terminal edge. In this embodiment or aspect, the terminal edge always deflects to the same rotational (e.g., clockwise or counterclockwise) direction as the start edge.

(26) As discussed above, the line retraction device 100 and speed reducer arrangement 200 of the present invention provide a reduction in the speed of the hub 2 in both rotational directions (e.g., releasing and retracting) when the at least one brake shoe 5 moves from the inactivated position to the activated position.

(27) With respect to FIGS. 1, 2, 9, and 10, and in one preferred and non-limiting embodiment or aspect, when the hub 2 of the speed reducer arrangement 200 of the present invention is stationary, the length direction of the at least one groove of the at least one brake shoe 5 deflects the line (L2) connecting the at least one groove 8 and the central axis (A) of the hub 2. In this manner, the at least one biasing member 6 generates a radial force towards the central axis (A) and pulls the at least one brake shoe 5 towards the central axis (A), thereby retaining the at least one brake shoe 5 in the inactivated position, i.e., the position nearest to the central axis (A).

(28) In one preferred and non-limiting embodiment or aspect, during the process of retracting the line 13, the hub 2 rotates in the first rotational direction, e.g., the clockwise direction, and when the speed of retracting is relatively low, the structure status of the speed reducer arrangement 200 (as illustrated in FIGS. 1, 2, 9, and 10) is in the inactivated position. Though the at least one brake shoe 5 is urged away from the central axis (A) by the centrifugal force, when the rotating speed of the hub 2 is lower, the centrifugal force is too low to overcome the radial force towards the central axis (A) provided by the at least one biasing member 6. Accordingly, the radial gap is maintained between the at least one brake shoe 5 and the at least one contact surface 32 of the housing 1 of the line retraction device 100, such that there will be no contact (or frictional engagement). However, when the speed of retracting the line 13 is higher, the structure status of the speed reducer arrangement 200 (as illustrated in FIGS. 3, 4, 10, and 11) is in the activated position. In this manner, the rotating speed of the hub 2 is higher, and, therefore, the centrifugal force on the at least one brake shoe 5 is higher. When the centrifugal force is high enough to overcome the radial force towards the central axis (A) provided by the at least one biasing member 6, the at least one brake shoe 5 will slide along the at least one groove 8 away from the central axis (A) of the hub 2 under the constraint of the at least one lug 4. When the at least one brake shoe 5 contacts the housing 1, frictional engagement will occur between the at least one brake shoe 5 and the at least one contact surface 32. Accordingly, this engagement will lead to deceleration of the at least one brake shoe 5, and since the at least one lug 4 is fixed to the at least one hub 2, which is restrained in the at least one groove 8, the speed of the hub 2 will correspondingly decrease at the same pace as the at least one brake shoe 5.

(29) In this embodiment or aspect, the faster the hub 2 is rotating, the higher the centrifugal force that will be applied on the at least one brake shoe 5. Since friction is in direct proportion to normal pressure, the friction between the at least one brake shoe 5 and the at least one contact surface 32 increases due to the increasing force of the normal pressure. Accordingly, the speed reducer arrangement 200 provides higher friction resistance when the hub 2 is rotating at a high rotating speed. One or both of the contact edge 35 of the at least one brake shoe 5 and the at least one contact surface 32 of the line retraction device 100 may be manufactured from or coated with a material with a high coefficient of friction. When the rotating speed of the hub 2 becomes lower, the frictional resistance becomes lower, such that the at least one brake shoe 5 will move back to the inactivated position, since the centrifugal force is too low to overcome the radial force towards the central axis (A) provided by the at least one biasing member 6. The process of retracting the line 13 illustrates how the speed reducer arrangement 200 automatically and proportionately adjusts the deceleration friction resistance with the change of the rotating speed of the hub 2, to ensure the decelerating effect results in a uniform (or constant) retraction speed.

(30) In one preferred and non-limiting embodiment or aspect, during the process of releasing, or paying out, the line 13, the hub 2 rotates in the second rotational direction, e.g., the counterclockwise direction, and when the speed of releasing is relatively low, the structure status of the speed reducer arrangement 200 is illustrated in FIGS. 1, 2, 9, and 10. Though the at least one brake shoe 5 is urged away from the central axis (A) due to the centrifugal force, when the rotating speed of the hub 2 is lower, the centrifugal force is too low to overcome the radial force towards the central axis (A) provided by the at least one biasing member 6. Therefore, the radial gap exists between the at least one brake shoe 5 and the at least one contact surface 32 of the line retraction device 200, such that no contact will occur. However, as discussed above, when the speed of releasing is higher, the structure status of the speed reducer arrangement 200 is illustrated in FIGS. 3, 4, 10, and 11. In this case, the rotating speed of the hub 2 is higher, and therefore, the centrifugal force on the at least one brake shoe 5 is higher. When the centrifugal force is high enough to overcome the radial force towards the central axis (A) provided by the at least one biasing member 6, the at least one brake shoe 5 will slide along the at least one groove 8 away from the central axis (A) of the hub 2 under the constraint of the at least one lug 4 to the activated position, thereby providing engagement and deceleration of the at least one brake shoe 5 due to the frictional resistance, which, as discussed above, is automatically proportional. Also, and again, when the rotating speed of the hub 2 becomes lower, the friction resistance becomes lower, and the at least one brake shoe 5 moves back to the inactivated position nearest to the central axis (A) when the centrifugal force is too small to overcome the radial force towards the central axis (A) provided by the at least one biasing member 6.

(31) In one preferred and non-limiting embodiment or aspect, the critical speed to move the at least one brake shoe 5 from the position nearest to the central axis (A) during the process of releasing the line 13 is higher than the critical speed to move the at least one brake shoe 5 from the position nearest to the central axis (A) during the process of retracting the line 13. The difference between the releasing critical speed and the retracting critical speed increases with the increase of the degree of the angle (B). This effect is realized, since, in one preferred and non-limiting embodiment or aspect, when the hub 2 is rotating in the first rotational direction, e.g., the clockwise direction, the speed reducer arrangement 200 increases the effect of the at least one brake shoe 5 moving to the activated position, because the at least one brake shoe 5 experiences the counterclockwise circumferential force from the direction of the at least one groove 8 to move away from the central axis (A), as well as the centrifugal force to radially move away from the central axis (A). Conversely, when the hub 2 is rotating in the second rotational direction, e.g., the counterclockwise direction, the speed reducer arrangement 200 decreases the effect of the at least one brake shoe 5 moving away from the central axis (A), because the at least one brake shoe 5 experiences the clockwise circumferential force from the direction of the at least one groove 8 to move toward the central axis (A), as well as the centrifugal force to radially move away from the central axis (A). Therefore, the difference between the releasing critical speed and the retracting critical speed can be effectively adjusted by adjusting the degree of the angle (B). More specifically, the larger the degree of the acute angle (B), the larger the difference in critical speeds.

(32) In one preferred and non-limiting embodiment or aspect, and when the speed reducer arrangement 200 of the present invention is used in practice, the application where the hub 2 is rotating in a high speed normally happens during the process of retracting the line 13 by the winding section 21, which typically occurs automatically. Therefore, it is preferable and beneficial to restrain the line 13 retracting speed during the automatically retracting process, so as to prevent the potential damage to the hub 2 or other connecting components. However, when releasing the line 13 from the winding section 21, the releasing process is typically gradual, such that it is not essential to restrain the line 13 releasing speed. Therefore, the difference between the two critical speeds during the process of releasing and retracting can be utilized and effectively adjusted by adjusting the degree of the angle (B).

(33) Accordingly, the present invention provides an improved line retraction device 100 and speed reducer arrangement 200 for use in a variety of applications and environments.

(34) For purposes of summarizing the invention, certain aspects, features and advantages of the invention have been described. It is herein to be understood that not all advantages of this invention can be achieved in relation to any particular embodiment. As such, the invention can be embodied in configurations to optimize one or various advantages. Applications of the invention can be indicated for any one advantage, or combination of advantages, as indicated for implementation.

(35) While several embodiments of the line retraction device and speed reducer arrangement are shown in the accompanying figures and described hereinabove in detail, other embodiments will be apparent to, and readily made by, those skilled in the art without departing from the scope and spirit of the invention. For example, it is to be understood that this disclosure contemplates that, to the extent possible, one or more features of any embodiment or aspect can be combined with one or more features of any other embodiment or aspect. Accordingly, the foregoing description is intended to be illustrative rather than restrictive.