Device for Securing a Tension Element Against Unintentional Release

Abstract

The invention relates to a device (14) for securing a clamping element against unintentional release, with a disk-shaped structure (15) that is penetrated in an axial manner by a bore hole (16). Thereby, the structure (15) is provided for an inner diameter with a driving profile (17) defined by the bore hole (16), which, in the placement of the structure (15), engages with the bore hole (16) on a radially inner component in a profile provided on the part of such component and thereby establishes a torque-proof coupling of the structure (15) with this component. In addition, the structure (15) is provided, in an axial manner on both sides, with contact surfaces (18, 19) that run in a radial manner. In order to provide a device that can be mounted on a radially inner component in a manner that is as free of backlash as possible and with low expenses, a profile plane (22) of the driving profile (17) is tilted at an angle () with respect to radial planes (20, 21) of the contact surfaces (18, 19).

Claims

1. Device (14) for securing a clamping element (11; 29) against unintentional release, with a disk-shaped structure (15) that is penetrated in an axial manner by a bore hole (16), whereas the structure (15) is provided for an inner diameter with a driving profile (17) defined by the bore hole (16), which, in the placement of the structure (15), engages with the bore hole (16) on a radially inner component in a profile (23) provided on the part of such component and thereby establishes a torque-proof coupling of the structure (15) with this component, and whereas the structure (15) is provided, in an axial manner on both sides, with contact surfaces (18, 19) that run in a radial manner, characterized in that a profile plane (22) of the driving profile (17) is tilted at an angle () with respect to radial planes (20, 21) of the contact surfaces (18, 19).

2-15. (canceled)

Description

[0024] Additional embodiments of the invention, which are described below, are shown in the drawings. The following is shown:

[0025] FIG. 1 a sectional view of a bearing assembly of a transmission shaft with a device according to a first embodiment of the invention;

[0026] FIG. 2 a detail view of the device from FIG. 1;

[0027] FIG. 3 a sectional view of the device cut along the line A-A in FIG. 2;

[0028] FIG. 4 a detail of the device from FIG. 2;

[0029] FIG. 5 a sectional view of a part of a transmission, with which a device is used according to a second embodiment of the invention;

[0030] FIG. 6A an exploded view of a gear selector for a transmission known from the prior art;

[0031] FIG. 6B a detailed drawing and a sectional view of the mounted gear selector from FIG. 6A;

[0032] FIG. 7 a sectional view of a gear selector for a transmission, with which a device is used according to a third embodiment of the invention;

[0033] FIG. 8 a detail view and a sectional view of the device from FIG. 7;

[0034] FIG. 9A a sectional view of a selector shaft of a gear selector for an automatic transmission;

[0035] FIG. 9B a sectional view of the selector shaft from FIG. 9A, with which a device is used according to a fourth embodiment of the invention; and

[0036] FIG. 10 a detail view and a sectional view of the device from FIG. 9B.

[0037] FIG. 1 shows a first application example of the invention. FIG. 1 shows a sectional view of a bearing assembly of a shaft 1 formed as a bevel pinion shaft. In this case, this bevel pinion shaft may be used, for example, for connecting an output side of an automatic transmission with an axle differential on the drive side of the automatic transmission. The shaft 1 is equipped at a front end with a bevel pinion 2, across which, in the installed state, a tooth engagement with a crown wheel of the axle differential is then established. By contrast, a spline 3 is formed at an end opposite to it.

[0038] As can be seen from FIG. 1, the bearing arrangement of the shaft 1 comprises two rolling bearings, which are placed in a bearing seat area at the shaft 1 following the bevel pinion 2 in an axially direct manner, and are present in the form of a tapered roller bearing 5 and an angular ball bearing 6. Thereby, both bearings are equipped with an internal ring 7 and 8 allocated to each, along with the respective associated external rings 9 and 10. In the present case, a pre-tensioning of the internal rings 7 and 8 of the two rolling bearings is ensured by means of a clamping element 11 in the form of a clamping nut, which is guided with an internal thread 12 to an external thread 13 of the shaft corresponding to it. Thereby, the clamping element 11 pre-tensions the internal rings 7 and 8 against the bevel pinion 2 of the shaft 1.

[0039] In the installed state of the bearing arrangement, in particular upon a change in loads, the internal rings 7 and 8 may carry out micro-movements relative to the shaft 1 in the form of minor twists. If such micro-movements are then transferred to the clamping element 11, a release of the clamping element 11 and thus a loss of the pre-tensioning could arise. Therefore, in order not to transfer this twisting to the tensioning element 11, a device 14 is placed in an axial manner between the angular ball bearing 6 and the clamping element 11, which device is arranged in a torque-proof manner at the shaft 1 and the exact structure of which is more specifically described with the assistance of the additional views of FIGS. 2 to 4 in the following: as can be seen in this case, the device 14 is formed by a one-piece, disk-shaped structure 15, which is penetrated by a bore hole 16 and therefore as a whole forms a ring shape. Within the bearing assembly in FIG. 1, the device 14 is set with the bore hole 16 on the shaft 1, whereas a torque-proof connection with the shaft 1 is realized by means of a driving profile 17, which is arranged at an inner diameter of the structure 15 defined by the bore hole 16.

[0040] As can be further seen from the sectional view of the device 14 in FIG. 3, the device 14 has, in an axial manner on both sides, the contact surfaces 18 and 19, of which, within the bearing assembly in FIG. 1, the contact surface 18 establishes a contact of the device 14 with the internal ring 8 and the contact surface 19 establishes a contact with the clamping element 11. Thereby, the contact surfaces 18 and 19 run in a radial manner into the planes 20 and 21 corresponding to each, and are aligned to each other in a parallel manner.

[0041] As a special feature, a profile plane 22, along which the driving profile 17 extends, now runs at an angle both at the plane 20 and the plane 21. As a result, the driving profile 17 is tilted from the radial line by the angle , whereas, in this case, the angle is (as an example) in the range of 1.5 to 2.5. Furthermore, the driving profile 17, as can be seen from the detail in FIG. 4 for the device 14, is designed as an involute toothing, which extends in the circumferential direction over the complete inner diameter of the structure 15 defined by the bore hole 16. The angle is calculated according to the formula

[00002]$j_n-\left[\left(d.Math.\sin .Math..Math.{}_t-\frac{j_n}{2}\right).Math.\cos .Math..Math.+\frac{b}{2}.Math.\sin .Math..Math.-\left(\left(d.Math.\sin .Math..Math.{}_t\right)-\frac{j_n}{2}\right)\right]0$

whereas j.sub.n forms a normal backlash of the involute toothing, at forms an operating pressure angle of the involute toothing and d forms a pitch circle diameter of the toothing.

[0042] If the bearing assembly in FIG. 1 is now mounted, after the placement of the two roller bearings on the bearing seat area 4, the device 14 is threaded on the shaft 1. Thereby, on the part of the shaft 1, a profile 23 corresponding to the driving profile 17 (that is, an involute toothing fit to the involute toothing of the device 14) is arranged. However, the profile 23 of the shaft 1 is aligned in a radial direction and thus, in contrast to the device 14, is not tilted at an angle. In addition, the driving profile 17 and the profile 23 are each designed for each other in such a manner that a clearance fit is predominant and the device 14 can be easily threaded accordingly.

[0043] However, if the clamping element 11 is now be screwed onto the shaft 1 and arrives in contact with the contact surface 19 of the device 14, the device 14 is subsequently pressed, also with its contact surface 18, at the internal ring 8. However, since the two contact surfaces 18 and 19 run to the profile plane 22 of the driving profile 17 at the angle , the clamping of the device 14 between the internal ring 8 and the clamping element 11 results in a tilting of the driving profile 17 to the profile 23 of the shaft 1 by the angle . Due to this tilting, the flanks 24 and 25 of the driving profile 17, which can be seen in FIG. 4, are, viewed across the circumference, pressed in areas at flanks (which in the present case are not shown in further detail) of the profile 23, and thus, in such areas, any backlash is reduced to 0 and to less than 0. Thereby, the clearance fit predominant upon the threading of the device 14, in some sections of the circumferential side, is transferred into press fits.

[0044] In the present case, the angle is selected to be so large that the formation of press fits takes place over the largest possible areas in the circumferential direction, whereas, on the part of the device 14 and, if applicable, the shaft 1, in addition to elastic deformations, plastic deformations will also arise, in part due to the selected angle . Due to the formation of press fits, the device 14 subsequently may no longer rotate with respect to the shaft 1, such that no micro-movements whatsoever can be transferred to the clamping element 11.

[0045] FIG. 5 shows a second application example of the invention. FIG. 5 shows a sectional view of part of a transmission 26, with which a mounting flange 27 is mounted on a shaft 28 designed as a drive shaft. The attachment is accomplished by means of a clamping element 29 formed as a clamping nut with the assistance of the device 14, whereas, in principle, the manner of the formation of the mounting corresponds to the variants described for FIGS. 1 to 4. In this respect, reference is made to the that described thereto.

[0046] FIG. 6A shows an exploded view of a gear selector 30 for an automatic transmission 26 known from the prior art; FIG. 6B shows a detailed drawing and a sectional view of this gear selector 30 in the mounted state. The gear selector 30 comprises a notched disk 31, a spring 32, a bearing 33, a shaft 34 designed as a selector shaft, a selector lever 36, a clamping element 38 and a spring pin 39. The notched disk 31 is plugged into the shaft 34, whereas the spring pin 39 establishes a positive-locking connection between the notched disk 31 and the shaft 34. The spring 32 that is likewise plugged into the shaft 34 is mounted by means of the bearing 33 on the shaft 34 and, with one of its two ends, engages in the notched disk 31 in a positive-locking manner. At the end of the shaft 34 opposite to the notched disk 31, a driving profile 35, into which the selector lever 36 is plugged, is provided. For this purpose, the selector lever 36 features a recess 37 corresponding to a driving profile 35. Counter to the release of the selector lever 36 from the shaft 34, the clamping element 38 designed as clamping nut is screwed into a corresponding external thread of the driving profile 35.

[0047] In this embodiment, the driving profile 35 is formed as a so-called dihedral profile, which is known from the prior art, at which the external thread that is provided at the end of the selector shaft 35 and corresponds to the internal thread of the clamping nut 38 is partially milled in a manner axially parallel to the center axis of the selector shaft 34 in such a manner that a flat surface arises to the left and right of the center axis of the selector shafts, whereas such two surfaces are oriented in a manner parallel to each other. Essentially, such a dihedral profile is a spline with a cog and a pressure angle of 0 degrees.

[0048] In the mounted state, the shaft 34 penetrates a housing bore hole 41 of a transmission housing 40 such that the notched disk 31, the spring 32 and the bearing 33 are, viewed spatially, arranged in the interior of the transmission housing 40, while the selector lever 36 and the clamping element 38 are, viewed spatially, arranged outside of the transmission housing 40. Thereby, the spring 32 pre-tensions the notched disk 31 with respect to the transmission housing 40. For actuating the gear selector 30, a Bowden cable (not shown more in more detail here) is provided, the free end of which engages in the selector lever 36 and the outer shell of which is supported at the transmission housing 40 by means of a Bowden cable holder 42.

[0049] In practice, vibrations of the transmission housing 40 and the automatic transmission 26 may lead to the undesired release of the clamping nut 38 at the thread of the selector shaft 34, with the result that the connection between the selector shaft 34 and the selector lever 36 is subject to backlash, by which the mechanical transmission of the shift command, introduced by the driver into the Bowden cable, to the notched disk 31 provided in the automatic transmission 26 for the selection of driving range and gears is undesirably inaccurate.

[0050] FIG. 7 shows a third application example of the invention. FIG. 7 shows a sectional view of a gear selector 30 for an automatic transmission, which is based on the design of the gear selector 30 known from FIGS. 6A/6B. Thereby, FIG. 7 shows the gear selector 30 in the mounted state, whereas, for the simplicity of the illustration, the transmission housing that is penetrated by the selector shaft 34 has been omitted in the drawing. In contrast to FIGS. 6A/6B, the force-fitting screw connection between the clamping element 38 and the shaft 34 is secured against unintentional release by the device 43 in accordance with the invention. Thereby, based on its tilting by the angle , the device 43 tensions the clamping element 38 formed as a clamping nut with respect to the selector lever 36, whereas, in principle, the manner of the formation of the mounting corresponds to the variants described for FIGS. 1 to 4. FIG. 8 shows an enlarged view (top view and section view) of the device 43 in accordance with the invention used in FIG. 7.

[0051] As can be seen in this case, the device 43 is formed by a one-piece, disk-shaped structure 44, which is penetrated in the axial direction with an inner contour 45. Within the gear selector 30, the device 43 is set with its inner contour 45 on the shaft 34 designed as a selector shaft, whereas a torque-proof connection with the shaft 34 is realized by means of a driving profile 46, which is arranged on the inner contour 45 of the structure 44.

[0052] The device 43 has, in an axial manner on both sides, the contact surfaces 47 and 48, of which, within the gear selector 30, the contact surface 47 establishes a contact of the device 43 with the selector lever 36 and the contact surface 48 establishes a contact with the clamping element 38. Thereby, the contact surfaces 47 and 48 run in a radial manner into the planes 49 and 50 corresponding to each, and are aligned to each other in a parallel manner.

[0053] As a special feature, a profile plane 51, along which the driving profile 46 extends, now runs at an angle both to the plane 49 and the plane 50. As a result, the driving profile 46 is tilted from the radial line by the angle , whereas, in this case, the angle is (as an example) in the range of 1.5 to 2.5. In other words, this means that the central axis of the driving profile 46 is tilted by the angle with respect to the central axis of the disk-shaped structure 44.

[0054] Within the framework of the assembly of the gear selector 30, the selector shaft 35 is initially completed with the notched disk 31, the spring pin 39, the bearing 33 and the spring 33. Subsequently, the pre-mounted selector shaft 34 is pushed from the interior of the transmission housing through the corresponding transmission housing bore hole, such that the shaft end of the selector shaft 34 provided with the profile 35 is outside of the transmission housing. Accordingly, the selector lever 36 is plugged into the free shaft end of the selector shaft 34. On the part of the selector lever 36, a recess 37 corresponding to the dihedral profile 35 of the selector shaft 34 is formed for this purpose. Subsequently, the device 43 is threaded onto the free shaft end of the selector shaft 34. On the part of the selector shaft 34, the profile 35 corresponding to the inner contour 46 of the device 43 is formed for this purpose; in the present application example, this is a dihedral profile fit to the driving profile 46 of the device 43. However, the profile 35 of the selector shaft 34 is aligned in the radial direction and, in contrast to the device 43, is not tilted at an angle. In addition, the driving profile 46 and the profile 35 are designed for each other in such a manner that a clearance fit is predominant and the device 43 can be easily threaded accordingly.

[0055] If, within the framework of the assembly of the gear selector 30, the clamping element 38 is now screwed onto the shaft 34, the clamping element 38 arrives in contact with the contact surface 48 of the device 43 and subsequently presses the device 43, with its contact surface 47, at the selector lever 36. However, since the two contact surfaces 47 and 48 run to the profile plane 51 of the driving profile 46 at the angle , the clamping of the device 43 between the selector lever 36 and the clamping element 38 results in a tilting of the driving profile 46 of the device 43 to the profile 35 of the selector shaft 34 by the angle , whereas the selector lever 36 on its part is supported on an abutment shoulder of the selector shaft 34. Due to this tilting, the flanks 52 and 53 of the driving profile 46 are pressed, at least in sections, at flanks of the profile 35, and thus, in such areas, any backlash is eliminated. Thereby, the clearance fit predominant upon the threading of the device 43, in some sections of the circumferential side, is transferred into press fits.

[0056] In the present case, the angle is selected to be so large that the formation of press fits takes place over the largest possible areas of the flanks 52, 53, whereas, on the part of the device 43 and, if applicable, the shaft 34, in addition to elastic deformations, plastic deformations may also arise, in part due to the selected angle . Due to the formation of press fits, the device 43 subsequently may no longer rotate with respect to the shaft 34, such that no micro-movements whatsoever can be transferred to the clamping element 38.

[0057] Based on FIGS. 9A, 9B and 10, a fourth application example of the invention will be explained in more detail below. FIG. 9A and FIG. 9B show a cut of a view of a shaft 54 formed as a selector shaft that, as an alternative to the shaft 34 provided in FIG. 7, may be used with the gear selector 30 shown in FIG. 7. In FIG. 9A, the selector shaft 54 is shown as an individual part. In FIG. 9B, the selector shaft 54 is shown in the mounted state, together with the selector lever 36, the device 57 in accordance with the invention and the clamping element 38 formed as a clamping nut. The (external) thread provided for screwing the clamping nut 38 onto the selector shaft 54 is designated with 56. In contrast to FIG. 7, in which the profile 35 provided for the positive-locking receiving of the selector lever 36 and the device 43 at the selector shaft 34 is formed as a so-called dihedral profile, in FIG. 9A/FIG. 9B, a profile 55, which is formed as a so-called square profile, is provided for the positive-locking receiving of the selector lever 36 and the device 54 at the selector shaft 54. Essentially, such a square profile is a spline with four cogs and a pressure angle of 45 degrees. FIG. 10 shows, in a top view and section view, the device 57 in accordance with the invention used in FIG. 9B as an individual part.

[0058] As can be seen in this case, the device 57 is formed by a one-piece, disk-shaped structure 58, which features a square-shaped outer contour and is penetrated in the axial direction with a square-shaped inner contour 59. Within the gear selector, the device 57 is set with its inner contour 59 on the shaft 54 designed as a selector shaft, whereas a torque-proof connection with the shaft 54 is realized by means of a driving profile 60, which is arranged on the inner contour 59 of the structure 58.

[0059] The device 57 has, in an axial manner on both sides, the contact surfaces 61 and 62, of which, within the gear selector, the contact surface 61 establishes a contact of the device 57 with the selector lever 36 and the contact surface 62 establishes a contact with the clamping element 38. Thereby, the contact surfaces 61 and 62 run in a radial manner into the planes 63 and 64 corresponding to each, and are aligned to each other in a parallel manner.

[0060] As a special feature, a profile plane 65, along which the driving profile 60 extends, now runs at an angle both to the plane 63 and the plane 64. As a result, the driving profile 60 is tilted from the radial line by the angle , whereas, in this case, the angle is (as an example) in the range of 1.5 to 2.5. In other words, this means that the central axis of the driving profile 60 is tilted by the angle with respect to the central axis of the disk-shaped structure 57.

[0061] Within the framework of the assembly of the gear selector, the selector shaft 54 completed with the notched disk, the spring pin, the bearing and the spring 33 is pushed from the interior of the transmission housing through the corresponding transmission housing bore hole, such that the shaft end of the selection shaft 54 provided with the profile 55 and the thread 56 is outside of the transmission housing. Accordingly, the selector lever 36 is plugged into the free shaft end of the selector shaft 54. On the part of the selector lever 36, a recess corresponding to the square profile 55 of the selector shaft 54 is formed for this purpose. Subsequently, the device 57 is threaded onto the free shaft end of the selector shaft 54. On the part of the selector shaft 54, the profile 55 corresponding to the inner contour 59 of the device 57 is formed for this purpose; in the present application example, this is a square profile fit to the driving profile 60 of the device 57. However, the profile 55 of the selector shaft 54 is aligned in the radial direction and, in contrast to the device 57, is not tilted at an angle. In addition, the driving profile 60 and the profile 55 are designed for each other in such a manner that a clearance fit is predominant and the device 57 can be easily threaded accordingly.

[0062] If, within the framework of the assembly of the gear selector, the clamping element 38 is now screwed onto the shaft 54, the clamping element 38 arrives in contact with the contact surface 62 of the device 57 and subsequently presses the device 57, with its contact surface 61, at the selector lever 36. However, since the two contact surfaces 61 and 62 run to the profile plane 65 of the driving profile 60 at the angle , the clamping of the device 57 between the selector lever 36 and the clamping element 38 results in a tilting of the driving profile 60 of the device 57 to the profile 55 of the selector shaft 54 by the angle , whereas the selector lever 36 on its part is supported on an abutment shoulder of the selector shaft 54. Due to this tilting, the flanks 66, 67, 68 and 69 of the driving profile 60 are pressed, at least in sections, at flanks of the profile 55, and thus, in such areas, any backlash is eliminated. Thereby, the clearance fit predominant upon the threading of the device 57, in some sections of the circumferential side, is transferred into press fits.

[0063] In the present case, the angle is selected to be so large that the formation of press fits takes place over the largest possible areas of the flanks 66, 67, 68, 69, whereas, on the part of the device 57 and, if applicable, the shaft 54, in addition to elastic deformations, plastic deformations may also arise, in part due to the selected angle . Due to the formation of press fits, the device 57 subsequently may no longer rotate with respect to the shaft 54, such that no micro-movements whatsoever can be transferred to the clamping element 38.

[0064] Thus, by means of the arrangement of a device in accordance with the invention, the securing of a clamping element against unintentional release can be realized in a reliable manner, with low installation costs at the same time. However, apart from a loss prevention device, a device in accordance with the invention may also be designed as a torque-transferring component, such as a gear wheel or a brake disk, whereas, in this case, the design in accordance with the invention of a device is used to form a press connection with a shaft coupled with it.

REFERENCE SIGNS

[0065] 1 Shaft; bevel pinion shaft

[0066] 2 Bevel pinion

[0067] 3 Spline

[0068] 4 Bearing seat area

[0069] 5 Tapered roller bearing

[0070] 6 Angular ball bearing

[0071] 7 Internal ring

[0072] 8 Internal ring

[0073] 9 External ring

[0074] 10 External ring

[0075] 11 Clamping element; clamping nut

[0076] 12 Internal thread

[0077] 13 External thread

[0078] 14 Device

[0079] 15 Structure

[0080] 16 Bore hole

[0081] 17 Driving profile

[0082] 18 Contact surface

[0083] 19 Contact surface

[0084] 20 Plane

[0085] 21 Plane

[0086] 22 Profile plane

[0087] 23 Profile; tooth profile

[0088] 24 Flank

[0089] 25 Flank

[0090] 26 Transmission; automatic transmission

[0091] 27 Mounting flange

[0092] 28 Shaft; drive shaft

[0093] 29 Clamping element; clamping nut

[0094] 30 Gear selector

[0095] 31 Notched disk

[0096] 32 Thread

[0097] 33 Bearing

[0098] 34 Shaft, selector shaft

[0099] 35 Profile; dihedral profile

[0100] 36 Selector lever

[0101] 37 Recess

[0102] 38 Clamping element; clamping nut

[0103] 39 Spring pin

[0104] 40 Transmission housing

[0105] 41 Transmission housing bore hole

[0106] 42 Bowden cable holder

[0107] 43 Device

[0108] 44 Structure

[0109] 45 Inner contour

[0110] 46 Driving profile

[0111] 47 Contact surface

[0112] 48 Contact surface

[0113] 49 Plane

[0114] 50 Plane

[0115] 51 Profile plane

[0116] 52 Flank

[0117] 53 Flank

[0118] 54 Shaft, selector shaft

[0119] 55 Profile; square profile

[0120] 56 Thread

[0121] 57 Device

[0122] 58 Structure

[0123] 59 Inner contour

[0124] 60 Driving profile

[0125] 61 Contact surface

[0126] 62 Contact surface

[0127] 63 Plane

[0128] 64 Plane

[0129] 65 Profile plane

[0130] 66 Flank

[0131] 67 Flank

[0132] 68 Flank

[0133] 69 Flank

[0134] Angle