Cramp device, coupling structure of the clamp device and rotational shaft, and steering device

Abstract

To provide a clamp device capable of reducing deformation resistance of a base part during tightening of a bolt, thereby increasing tightening force.SOLUTION: A clamp device comprises a base part 20 having a cylindrical shape and a pair of flange parts 21a, 21b. The base part 20 has: an insertion hole 25 that extends in an axial direction; a slit 22 that is arranged at one circumferential location and extends in the axial direction; meshing parts 26a to 26c that comprise female serration teeth 29 on their inner peripheral surfaces; and first non-meshing parts 27a, 27b that do not comprise the female serration teeth 29 on their inner peripheral surfaces. The inner peripheral surfaces of the first non-meshing parts 27a, 27b are located radially outward with respect to a tooth bottom circle S29 of the female serration teeth 29, and outer peripheral surfaces 36a, 36b are located radially outward with respect to an imaginary circle S26 that passes through partially cylindrical outer peripheral surfaces 35a to 35c of the meshing parts 26a to 26c centering on a central axis O25 of the insertion hole 25.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present disclosure relates to a clamp device, a coupling structure between the clamp device and a rotating shaft, and a steering device including the clamp device. [Background technology]

[0002] A steering device for an automobile is used to impart a steering angle to a steering wheel.

[0003] In a steering device, the rotation of the steering wheel is transmitted to the pinion shaft of the steering gear unit via a steering shaft, an intermediate shaft, etc. The rotation of the pinion shaft is converted into linear motion of the rack shaft of the steering gear unit, which gives the steered wheels a steering angle that corresponds to the amount of rotation of the steering wheel.

[0004] In a steering device, ends of two rotating shafts that are not coaxial with each other, such as a steering shaft and an intermediate shaft, are connected to each other via a universal joint so as to be able to transmit torque.

[0005] The universal joint includes a pair of yokes and a cross shaft.

[0006] The yoke that constitutes the universal joint is a type of clamp device, and has a cylindrical base portion, a pair of flange portions, and a pair of arm portions connected to the cross shaft.

[0007] The base has a slit extending in the axial direction at one location in the circumferential direction and is configured to be able to reduce its diameter. An end of a rotating shaft such as a steering shaft or a pinion shaft is inserted inside the base. A pair of flanges are provided on both sides of the slit in the circumferential direction. The pair of flanges have mounting holes arranged coaxially. The yoke is fixed to the rotating shaft by the base tightening the rotating shaft with a bolt inserted through one mounting hole provided in one of the pair of flanges and screwing it into the other mounting hole provided in the other flange.

[0008] Yokes are roughly classified into so-called open slit type yokes and so-called closed slit type yokes, depending on the difference in the structure of the slits provided in the base.

[0009] The closed slit type yoke is preferably used for applications that transmit high torque because it is easier to ensure strength compared to the open slit type yoke.

[0010] Fig. 28 shows an example of a conventional structure of an open slit type yoke 100a, and Fig. 29 shows an example of a conventional structure of a closed slit type yoke 100b.

[0011] Open slit type yoke 100a has a slit 102a with open ends on both axial ends at one location on base 101a in the circumferential direction, while closed slit type yoke 100b has a slit 102b with a closed end on one axial end and an open end on the other axial end at one location on base 101b in the circumferential direction.

[0012] The closed slit type yoke 100b has a higher flexural rigidity and tends to have a higher deformation resistance than the open slit type yoke 100a. Therefore, when a bolt (not shown) is tightened with the same torque, the tightening force of the closed slit type yoke 100b tends to be smaller than the tightening force of the open slit type yoke 100a.

[0013] When the closed slit type yoke 100b is incorporated into a column-assist type electric power steering device that transmits high torque, the end of the rotating shaft may slide slightly against the base 101b due to insufficient tightening force. As a result, damage such as fretting wear and fretting corrosion may progress to the female serration teeth provided on the inner peripheral surface of the base 101b and / or the male serration teeth provided on the outer peripheral surface of the rotating shaft.

[0014] In view of these circumstances, techniques for increasing the tightening force of closed slit type yokes have been devised.

[0015] JP 2022-15860 A describes a technology in which a thin-walled portion is provided on the outer circumferential surface of the base, including a portion of the base that is circumferentially shifted approximately ±45 degrees from the radially opposite portion of the slit, thereby reducing the deformation resistance of the base when the bolt is tightened and increasing the tightening force of the yoke.

[0016] In the conventional structure described in JP 2022-15860 A, the inner surface of the thin-walled portion of the base is a cylindrical surface that does not have female serration teeth, thereby preventing the surface pressure between the female serration teeth on the inner surface of the base and the male serration teeth on the outer surface of the rotating shaft from becoming excessively high in some areas, and this also increases the tightening force of the yoke. [Prior art documents] [Patent documents]

[0017] [Patent Document 1] Patent Publication No. 2022-15860 Summary of the Invention [Problem to be solved by the invention]

[0018] In the conventional yoke structure described in JP 2022-15860 A, a thin-walled portion is formed at the base by removing the thickness of the outer peripheral surface of the base, but there is a limit to the amount of thickness that can be removed from the outer peripheral surface of the base. For this reason, there is room for improvement in terms of sufficiently reducing the deformation resistance of the base and further increasing the tightening force of the yoke.

[0019] The problem described above is not limited to yokes that constitute universal joints that connect two rotating shafts that are not arranged coaxially, but can also occur in clamping devices other than yokes, such as coupling devices that connect two rotating shafts that are arranged coaxially.

[0020] An object of the present disclosure is to provide a clamp device capable of reducing the deformation resistance of the base and increasing the tightening force. [Means for solving the problem]

[0021] A clamp device according to one aspect of the present disclosure includes a base portion having a generally cylindrical shape and a pair of flange portions.

[0022] The base portion has an insertion hole extending in the axial direction, a slit arranged at one location in the circumferential direction and extending in the axial direction, an engaging portion having female serration teeth on its inner surface, and a non-engaging portion having no female serration teeth on its inner surface.

[0023] The interlocking portion has an outer peripheral surface having a partial cylindrical shape centered on the central axis of the insertion hole, and is provided at three locations on the base: a portion radially opposite the slit, and portions on both sides of an imaginary plane including the central axis of the insertion hole and the central axis of the slit.

[0024] The non-interlocking portion has an inner surface located radially outward from the bottom circle of the female serration tooth of the interlocking portion, and an outer peripheral surface located radially outward from an imaginary circle passing through the partially cylindrical outer peripheral surface of the interlocking portion with the central axis of the insertion hole as its center, and is provided at two locations on both circumferential sides of the interlocking portion located radially opposite the slit.

[0025] The pair of flange portions have coaxial mounting holes and are disposed on both sides of the slit in the circumferential direction.

[0026] In the clamp device according to one aspect of the present disclosure, the base has a second non-engagement portion, which does not have the female serration teeth on its inner circumferential surface, in a portion spanning the slit in the circumferential direction.

[0027] In a clamp device according to one aspect of the present disclosure, the non-interlocking portion has a cut-out portion on the inner circumferential surface, and the thickness of the cut-out portion of the non-interlocking portion is smaller than the thickness of the interlocking portion.

[0028] When the cut-out portion is provided on the inner circumferential surface of the non-meshing portion, the cut-out portion may be provided only at a portion that overlaps with the slit in the axial direction. Alternatively, the cut-out portion may be provided over the entire axial length of the inner circumferential surface of the non-engagement portion.

[0029] In the clamp device according to one aspect of the present disclosure, the pair of flange portions are integral with the base portion.

[0030] Alternatively, the pair of flange portions may be separate from the base portion.

[0031] The clamp device according to one aspect of the present disclosure further includes a connecting portion that is connected to another member in a torque-transmittable manner.

[0032] In the clamp device according to one aspect of the present disclosure, the connecting portion is made of a pair of arms provided adjacent to each other in the axial direction of the base portion. In this case, the clamp device is made of a yoke constituting a universal joint.

[0033] In the clamp device according to one aspect of the present disclosure, one of the pair of arms is disposed at a position where its phase in the circumferential direction coincides with that of the slit.

[0034] In the clamp device according to one aspect of the present disclosure, the connecting portion may be configured by a male shaft portion having male serration teeth or male spline teeth on an outer peripheral surface, a female shaft portion having female serration teeth or female spline teeth on an inner peripheral surface, or a key engagement portion, which are arranged coaxially with the base and adjacent to the base in the axial direction. In this case, the clamp device can connect the ends of two coaxially arranged rotating shafts to each other in a torque transmittable manner by fitting the connecting portion to an end of a mating member so as not to rotate relative to the mating member.

[0035] A coupling structure between a clamp device and a rotating shaft according to one aspect of the present disclosure includes a clamp device according to one aspect of the present disclosure, and a rotating shaft that rotates in use and is inserted into the insertion hole.

[0036] The rotating shaft has male serration teeth on its outer circumferential surface.

[0037] When the rotating shaft is inserted into the insertion hole and the diameter of the base portion is reduced, a gap exists between the male serration teeth and the inner peripheral surface of the non-meshing portion.

[0038] A steering device according to one embodiment of the present disclosure includes two rotating shafts that are not arranged on the same axis and that rotate by operating a steering wheel, and a universal joint that connects the ends of the two rotating shafts to each other so as to transmit torque.

[0039] The universal joint includes a pair of yokes and a cross shaft.

[0040] In the clamp device according to the above aspect, at least one of the pair of yokes has the pair of arm portions.

[0041] A steering device according to one embodiment of the present disclosure includes two coaxially arranged rotating shafts that rotate by operation of a steering wheel, and a coupling device that connects the ends of the two rotating shafts to each other so as to transmit torque.

[0042] The connecting device is the clamp device according to the aspect not having the connecting portion, or the clamp device according to the one aspect having the connecting portion other than the pair of arm portions. Effect of the Invention

[0043] According to the clamp device according to one aspect of the present disclosure, the deformation resistance of the base can be reduced and the clamping force can be increased. [Brief description of the drawings]

[0044] [Figure 1] FIG. 1 is a partial cutaway side view showing a steering device according to a first example of an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a cross-sectional view taken along line AA in FIG. [Diagram 3] FIG. 3 is a side view of the universal joint that connects the intermediate shaft and the pinion shaft in the first example. [Figure 4] FIG. 4 is a diagram showing a first yoke which is a clamp device of the first example. [Diagram 5] FIG. 5 is a diagram showing the first yoke of the first example rotated 180 degrees around the central axis from the state shown in FIG. [Figure 6] FIG. 6 is a view of the first yoke of the first example seen from above in FIG. [Figure 7] FIG. 7 is a view of the first yoke of the first example seen from below in FIG. [Figure 8] FIG. 8 is an end view of the first yoke of the first example as viewed from the left side of FIG. [Figure 9] FIG. 9 is a partially enlarged view of FIG. [Figure 10] FIG. 10 is a cross-sectional view taken along line BB in FIG. [Figure 11] FIG. 11 is a perspective view of the first yoke of the first example as viewed from the left side of FIG. [Figure 12] FIG. 12 is a view corresponding to FIG. 8, showing a state in which an end of a pinion shaft is inserted into the first yoke of the first example. [Figure 13] FIG. 13 is a diagram corresponding to FIG. 8 and relating to a second example of the embodiment of the present disclosure. [Figure 14] FIG. 14 is a diagram corresponding to FIG. 9 and relating to a second example of the embodiment of the present disclosure. [Figure 15] FIG. 15 is a diagram corresponding to FIG. 11 and relating to a second example of the embodiment of the present disclosure. [Figure 16] FIG. 16 is a diagram corresponding to FIG. 12 and relating to a second example of the embodiment of the present disclosure. [Figure 17]FIG. 17 is a diagram corresponding to FIG. 8 and relating to a third example of the embodiment of the present disclosure. [Figure 18] FIG. 18 is a diagram corresponding to FIG. 9 and relating to a third example of the embodiment of the present disclosure. [Figure 19] FIG. 19 is a diagram corresponding to FIG. 10 and relating to a third example of the embodiment of the present disclosure. [Figure 20] FIG. 20 is a half-sectional perspective view of a first yoke of the third example. [Figure 21] FIG. 21 is a diagram corresponding to FIG. 11 and relating to a third example of the embodiment of the present disclosure. [Figure 22] FIG. 22 is a diagram corresponding to FIG. 12 and relating to a third example of the embodiment of the present disclosure. [Diagram 23] FIG. 23 is a view corresponding to FIG. 4 and illustrating a state in which an end of a pinion shaft is inserted into a first yoke according to a fourth embodiment of the present disclosure. [Figure 24] FIG. 24 is a diagram corresponding to FIG. 12 and relating to a fourth example of the embodiment of the present disclosure. [Diagram 25] FIG. 25 is a side view showing an intermediate shaft constituting a steering device according to a fifth example of an embodiment of the present disclosure. [Figure 26] FIG. 26 is a diagram corresponding to FIG. 4 and relating to the fifth example. [Figure 27] FIG. 27 is a diagram corresponding to FIG. 6 and relating to the fifth example. [Figure 28] FIG. 28 is a perspective view showing an example of a conventional structure of an open slit type yoke. [Figure 29] FIG. 29 is a perspective view showing an example of a conventional structure of a closed slit type yoke. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0045] [Example 1] A first example of an embodiment of the present disclosure will be described with reference to FIGS. 1 to 12. FIG.

[0046] This example is an example in which a clamp device according to one aspect of the present disclosure is applied to a yoke that constitutes a universal joint incorporated in a steering device for an automobile.

[0047] [Outline of the steering system] The steering device 1 is a column-assist type electric power steering device, the overall configuration of which is shown in FIG.

[0048] The steering device 1 includes a steering wheel 2, a steering shaft 3, a steering column 4, two universal joints 5a, 5b, an intermediate shaft 6, a steering gear unit 7, a pair of tie rods 8, and an electric assist device 9.

[0049] The steering shaft 3 is rotatably supported inside a steering column 4 supported on the vehicle body. A steering wheel 2 operated by a driver is fixed to the rear end of the steering shaft 3. The front end of the steering shaft 3 is inserted inside a gear housing 10 fixed to the steering column 4, and is connected to an output shaft 12 via a torsion bar 11.

[0050] The front-rear direction refers to the front-rear direction of the vehicle in which the steering device 1 is mounted.

[0051] The rotation of the output shaft 12 is transmitted to a pinion shaft 13 constituting a steering gear unit 7 via two universal joints 5a, 5b and an intermediate shaft 6. The rotation of the pinion shaft 13 is converted into linear motion of a rack shaft meshed with the pinion shaft 13, which pushes and pulls a pair of tie rods 8. As a result, a steering angle according to the amount of operation of the steering wheel 2 is imparted to the steered wheels.

[0052] As shown in FIG. 2, the electric assist device 9 includes a torque sensor 14, an ECU (not shown), an electric motor 15, and a worm reduction gear 16.

[0053] The torque sensor 14 is disposed around the output shaft 12 and detects the relative torsion direction and amount of torsion of the output shaft 12 with respect to the steering shaft 3. The ECU determines the assist torque based on the detection signal of the torque sensor 14 and a vehicle speed signal measured by a vehicle speed sensor (not shown), etc. The electric motor 15 is fixed to the gear housing 10, and the direction and amount of current flow are controlled by the ECU. The worm reduction gear 16 reduces the rotational force of the electric motor 15 and transmits it to the output shaft 12. The electric assist device 9 imparts an assist torque to the output shaft 12 and reduces the steering force required for the driver to operate the steering wheel 2.

[0054] The intermediate shaft 6 and the output shaft 12 are two rotating shafts that are not arranged coaxially and rotate by operating the steering wheel 2. The universal joint 5a connects the respective ends of the intermediate shaft 6 and the output shaft 12 to each other in a manner enabling torque transmission.

[0055] The intermediate shaft 6 and the pinion shaft 13 are two rotating shafts that are not arranged coaxially and rotate by operating the steering wheel 2. The universal joint 5b connects the respective ends of the intermediate shaft 6 and the pinion shaft 13 to each other in a manner capable of transmitting torque.

[0056] 3, the universal joint 5b is composed of a first yoke 17 corresponding to a clamp device fixed to an end of the pinion shaft 13, a second yoke 18 fixed to an end of the intermediate shaft 6, and a cross shaft 19. In this example, the clamp device according to one embodiment of the present disclosure is applied to the first yoke 17 of the first yoke 17 and second yoke 18 constituting the universal joint 5b.

[0057] The clamp device according to an embodiment of the present disclosure may be applied to the second yoke 18 instead of the first yoke 17, or may be applied to both the first yoke 17 and the second yoke 18. Additionally or alternatively, the clamp device according to an embodiment of the present disclosure may be applied to at least one of the pair of yokes constituting the universal joint 5a. In these cases, the same configuration as the first yoke is adopted, and therefore the description thereof is omitted in this specification.

[0058] Hereinafter, the first yoke 17 and the coupling structure between the first yoke 17 and the pinion shaft 13 will be described with reference to FIGS.

[0059] [Yoke structure] The first yoke 17 is a so-called closed slit type yoke, and includes a base portion 20 having a substantially cylindrical shape and a pair of flange portions 21a, 21b.

[0060] The base 20 has a slit 22 extending in the axial direction at one location in the circumferential direction and is configured to be able to reduce its diameter. The pair of flange portions 21a, 21b are disposed on both sides of the slit 22 in the circumferential direction of the base 20. The first yoke 17 is fixed to the pinion shaft 13 by tightening the base 20 to the end of the pinion shaft 13 by screwing a bolt 24 (see FIG. 3) inserted through a mounting hole 23a provided in one flange portion 21a into a mounting hole 23b provided in the other flange portion 21b and further tightening the bolt.

[0061] The axial direction, circumferential direction, and radial direction of the first yoke 17 refer to the axial direction, circumferential direction, and radial direction of the base 20, unless otherwise specified. One axial side refers to the right side in Figs. 3 to 7 and 10, and the other axial side refers to the left side in Figs. 3 to 7 and 10. The front-back direction in Figs. 4 and 5, the up-down direction in Figs. 6 and 7, and the left-right direction in Figs. 8 and 9, which are perpendicular to the axial direction of the base 20, are referred to as the first direction. The first direction coincides with the central axial direction of the mounting holes 23a and 23b. The up-down direction in Figs. 4 and 5, the front-back direction in Figs. 6 and 7, and the up-down direction in Figs. 8 and 9, which are perpendicular to the axial direction and the first direction of the base 20, are referred to as the second direction.

[0062] A slit is a narrow gap whose width is smaller than its length.

[0063] The first yoke 17 is made of a metal material by subjecting it to, for example, forging and cutting processes.

[0064] The base portion 20 has an insertion hole 25, a slit 22, meshing portions 26a to 26c, and first non-meshing portions 27a and 27b which are the non-meshing portions described in the claims.

[0065] The insertion hole 25 opens at least on the other axial end face of the base 20 and extends in the axial direction. In this example, the insertion hole 25 passes through the base 20 in the axial direction. Specifically, the insertion hole 25 passes through the radial center of the base 20 in the axial direction. That is, the central axis O of the insertion hole 25 is 25 coincides with the central axis of the base 20. One axial end of the pinion shaft 13 is inserted into the insertion hole 25. The insertion hole is not limited to a through hole that passes through the base in the axial direction, but may be a bottomed hole that opens only on the end face on the other axial side of the base.

[0066] The insertion hole 25 has a cross-sectional shape in the shape of a partial gear.

[0067] Specifically, the insertion hole 25 is formed by a serration hole on the inner surface of the base 20, in which female serration teeth 29 and a first toothless portion 30 and a second toothless portion 31 in which the female serration teeth 29 are not formed are arranged in the circumferential direction.

[0068] The female serration teeth 29 engage with the male serration teeth 32 (see FIG. 12) provided on the outer peripheral surface of the end of the pinion shaft 13 so as to be non-rotatable relative to each other. In contrast, the first toothless portion 30 and the second toothless portion 31 do not engage with the male serration teeth 32.

[0069] In this example, the female serration teeth 29, the first toothless portion 30 and the second toothless portion 31 are formed on the inner peripheral surface of the base portion 20 in a range extending from one axial end to the other axial end.

[0070] The female serration teeth 29, the first toothless portion 30 and the second toothless portion 31 are formed, for example, by broaching using a broach tool.

[0071] The slit 22 is disposed at one location in the circumferential direction of the base 20 and extends in the axial direction. The length direction of the slit 22 coincides with the axial direction, the width direction of the slit 22 coincides with the first direction, and the depth direction of the slit 22 coincides with the second direction.

[0072] The slit 22 extends linearly in the axial direction. 22 is the central axis O of the insertion hole 25 25 are arranged approximately parallel to each other.

[0073] The slits 22 open on the outer circumferential surface and the inner circumferential surface of the base portion 20 .

[0074] The slit 22 is formed in a range extending from the other axial end of the base portion 20 to the axial middle portion.

[0075] An end of the slit 22 on one axial side is a closed end 33 that is closed in the axial direction, and an end of the slit 22 on the other axial side is an open end 34 that is open in the axial direction. In other words, the slit 22 does not open on the end face of the base 20 on one axial side, but opens on the end face of the base 20 on the other axial side. The closed end 33 is located in the middle of the base 20 in the axial direction.

[0076] When viewed from the second direction, the slit 22 has a rectangular opening shape that is long in the axial direction.

[0077] Width dimension W of slit 22 22 is constant over the entire length of the slit 22 before the bolt 24 is tightened. However, the width dimension of the slit may be varied depending on the axial position of the slit.

[0078] The closed end 33 of the slit 22 is aligned with the central axis O of the insertion hole 25. 25 and is constituted by a concave cylindrical surface having an arc-shaped cross section in a cross section perpendicular to the first direction. In other words, the closed end 33 is constituted by a partial cylindrical surface that is inclined toward one axial side as it goes radially outward and faces radially outward.

[0079] However, when implementing the present disclosure, the closed end of the slit may be formed by a plane perpendicular to the central axis of the insertion hole, or may be formed by a partial cylindrical surface that is approximately semicircular arc shaped when viewed from the second direction.

[0080] The slits 22 are formed, for example, by cutting using a cutter, which is a rotary cutting tool.

[0081] However, when implementing the present disclosure, the slits may be formed by methods other than cutting.

[0082] The base portion 20 of this embodiment is not completely cylindrical, but has a substantially cylindrical shape with two circumferentially bulging portions compared to the other portions.

[0083] The base portion 20 is configured by connecting a plurality of parts (elements) having different structures on the outer circumferential surface and the inner circumferential surface in the circumferential direction.

[0084] The base 20 has meshing portions 26a-26c and first non-meshing portions 27a, 27b, which have different structures on the outer circumferential surface and the inner circumferential surface. In this example, the base 20 further has a second non-meshing portion 28 in addition to the meshing portions 26a-26c and the first non-meshing portions 27a, 27b.

[0085] When implementing the present disclosure, the base portion does not necessarily have to have the second non-interlocking portion as long as it has the interlocking portion and the first non-interlocking portion.

[0086] The base 20 is configured by connecting in the circumferential direction the meshing portions 26a to 26c, the first non-meshing portions 27a, 27b, and the second non-meshing portion 28. Specifically, the base 20 is configured by connecting in the circumferential direction the meshing portions 26a to 26c provided at three locations in the circumferential direction, the first non-meshing portions 27a, 27b provided at two locations in the circumferential direction, and the second non-meshing portion 28 provided at one location in the circumferential direction.

[0087] The meshing portions 26a to 26c, the first non-meshing portions 27a, 27b, and the second non-meshing portion 28 are provided over the entire axial length of the base portion 20.

[0088] The meshing portions 26a to 26c are formed on the base 20 at a position radially opposite the slit 22 and the central axis O of the insertion hole 25. 25 and the central axis O of the slit 22 22 The projections are provided at three locations in total, one on each side of a virtual plane β that includes the projections.

[0089] Of the meshing portions 26a to 26c, one meshing portion 26a is provided on the radially opposite portion of the base 20 from the slit 22, and the remaining two meshing portions 26b, 26c are provided on both sides of the imaginary plane β.

[0090] In this example, the meshing portions 26b, 26c are provided in a range of the base portion 20 that includes a portion that is shifted from the slit 22 in the circumferential direction by approximately ±45 degrees.

[0091] Central axis O of the insertion hole 25 25 The central angle of the meshing portions 26a to 26c about the central axis O of the insertion hole 25 is not particularly limited. 25 The central angle of the meshing portion 26a about the central axis O of the insertion hole 25 is about 70 degrees. 25 The central angle of the meshing portions 26b, 26c about the center is approximately 30 degrees.

[0092] The first non-meshing portions 27a, 27b are provided at two locations in total on the base 20, on both circumferential sides of the meshing portion 26a located on the radially opposite side of the slit 22.

[0093] The first non-meshing portion 27a is provided between the meshing portions 26a, 26b adjacent to each other in the circumferential direction, and the first non-meshing portion 27b is provided between the meshing portions 26a, 26c adjacent to each other in the circumferential direction.

[0094] In this example, the first non-meshing portions 27a, 27b are provided in a range including a portion of the base 20 that is shifted approximately ±45 degrees in the circumferential direction from the portion radially opposite the slit 22.

[0095] Central axis O of the insertion hole 25 25 The central angle of the first non-meshing portions 27a, 27b about the central axis O of the insertion hole 25 is not particularly limited. 25 The central angle of the first non-meshing portions 27a, 27b about the center is approximately 80 degrees.

[0096] The second non-meshing portion 28 is provided at only one location in a portion of the base 20 that straddles the slit 22 in the circumferential direction. In other words, the slit 22 is formed in a circumferential intermediate portion (center portion) of the other axial half of the second non-meshing portion 28.

[0097] Central axis O of the insertion hole 2525 The central angle of the second non-meshing portion 28 about the central axis O of the insertion hole 25 is not particularly limited. 25 The central angle of the second non-meshing portion 28 about the center is approximately 70 degrees.

[0098] When the base 20 is viewed from the other axial side, the meshing portions 26a to 26c, the first non-meshing portions 27a, 27b and the second non-meshing portion 28 are arranged counterclockwise from the radially opposite portion of the slit 22 in the following order: meshing portion 26a → first non-meshing portion 27a → meshing portion 26b → second non-meshing portion 28 → meshing portion 26c → first non-meshing portion 27b.

[0099] Female serration teeth 29 are provided on the inner peripheral surfaces of the meshing portions 26a to 26c.

[0100] The number of teeth of the female serration teeth 29 may be different for each of the meshing portions 26a to 26c, but the pitch, tooth height, tip diameter and bottom diameter of the female serration teeth 29 are the same for each of the meshing portions 26a to 26c.

[0101] The meshing portions 26a to 26c are aligned along the central axis O of the insertion hole 25. 25 The outer circumferential surfaces 35a to 35c are partially cylindrical with the center at the center.

[0102] In this example, the meshing portion 26a has a partially cylindrical outer peripheral surface 35a only at the circumferential center, whereas the meshing portions 26b, 26c have partially cylindrical outer peripheral surfaces 35b, 35c over the entire circumferential direction.

[0103] The first non-mesh portions 27a, 27b have a shape that bulges outward in the radial direction relative to the circumferentially adjacent mesh portions 26a, 26b and mesh portions 26a, 26c.

[0104] The first non-meshing portions 27a, 27b have an arc-shaped cross section, and are configured as a partial cylinder as a whole.

[0105] The first non-meshing portions 27a, 27b are not provided with female serration teeth 29 on their inner circumferential surfaces, but are provided with first toothless portions 30.

[0106] The first toothless portion 30, which is the inner peripheral surface of the first non-meshing portions 27a, 27b, is entirely within the tooth root circle S of the female serration teeth 29. 29 It is located radially outwardly of the

[0107] The first toothless portion 30 has a radius of curvature r smaller than the radius of the bottom circle of the female serration tooth 29. 27 9. The center of curvature of the first toothless portion 30 of the first non-meshing portion 27a is located closer to the first non-meshing portion 27a than the imaginary plane β in the first direction, and the center of curvature of the first toothless portion 30 of the first non-meshing portion 27b is located closer to the first non-meshing portion 27b than the imaginary plane β in the first direction. In this example, the center of curvature of the first toothless portion 30 of the first non-meshing portion 27a and the center of curvature of the first toothless portion 30 of the first non-meshing portion 27b are located closer to the central axis O of the insertion hole 25 in the second direction in FIG. 25 In this example, the first toothless portion 30 is formed by a concave cylindrical surface.

[0108] The outer circumferential surfaces 36a, 36b of the first non-meshing portions 27a, 27b are aligned with the central axis O of the insertion hole 25. 25 A virtual circle S passing through the partially cylindrical outer circumferential surfaces 35a to 35c of the meshing portions 26a to 26c with the center at 26 It is located radially outwardly of the

[0109] The outer circumferential surfaces 36a, 36b of the first non-meshing portions 27a, 27b are aligned along the imaginary circle S 26 A radius of curvature R smaller than the radius of 27The first non-meshing portion 27a is configured by a convex curved surface having a curvature center of the first non-meshing portion 27a. The curvature center of the outer peripheral surface 36a of the first non-meshing portion 27a is located closer to the first non-meshing portion 27a than the imaginary plane β in the first direction, and substantially coincides with the curvature center of the first toothless portion 30 provided on the inner peripheral surface of the first non-meshing portion 27a. The curvature center of the outer peripheral surface 36b of the first non-meshing portion 27b is located closer to the first non-meshing portion 27b than the imaginary plane β in the first direction, and substantially coincides with the curvature center of the first toothless portion 30 provided on the inner peripheral surface of the first non-meshing portion 27a. In this example, the outer peripheral surfaces 36a, 36b of the first non-meshing portions 27a, 27b are configured by convex cylindrical surfaces.

[0110] The second non-interlocking portion 28 has a partially cylindrical shape except for the portion where the slit 22 is formed.

[0111] The second non-meshing portion 28 does not have any female serration teeth 29 on its inner circumferential surface, but has a second toothless portion 31 .

[0112] The second toothless portion 31 is aligned with the central axis O of the insertion hole 25. 25 The second toothless portion 31 has an inner diameter equal to the diameter of the bottom circle of the female serration tooth 29.

[0113] The outer circumferential surface of the second non-meshing portion 28 is aligned with the central axis O of the insertion hole 25. 25 The virtual circle S is configured as a partial cylindrical surface having a center at 26 Therefore, the outer circumferential surface of the second non-mesh portion 28 is smoothly continuous with the outer circumferential surfaces 35b, 35c of the mesh portions 26b, 26c in the circumferential direction.

[0114] In this example, the thickness (radial thickness dimension) of the first non-meshing portions 27a, 27b is substantially the same as the thickness of the meshing portions 26a to 26c. Note that the thickness of the meshing portions 26a to 26c refers to the radial thickness dimension not including the tooth height of the female serration teeth 29.

[0115] The thickness of the first non-meshing portions 27a, 27b is approximately the same as the thickness of the second non-meshing portion .

[0116] The base portion 20 of the present embodiment is configured by connecting the meshing portions 26a to 26c, the first non-mesh portions 27a and 27b, and the second non-mesh portion 28 in the circumferential direction as described above. 25 Across an imaginary plane γ that passes through and is perpendicular to the imaginary plane β, the half opposite the slit 22 (the upper part in Figures 8 and 9) has a roughly elliptical cylindrical shape, and the half opposite the slit 22 (the lower part in Figures 8 and 9) has a roughly cylindrical shape.

[0117] The pair of flange portions 21a, 21b are disposed on both sides of the slit 22 in the circumferential direction.

[0118] The pair of flange portions 21a, 21b are provided on the outer peripheral surface of the end portion on the other axial side of the base portion 20. The pair of flange portions 21a, 21b each protrude in a second direction from a portion of the outer peripheral surface of the base portion 20 that is located on both sides of the slit 22 in the circumferential direction. Each of the pair of flange portions 21a, 21b has a plate shape.

[0119] In this example, the pair of flange portions 21a, 21b have a substantially semicircular side shape when viewed from the first direction.

[0120] In this example, the pair of flange portions 21a, 21b are integral with the base portion 20. Specifically, the base ends of the pair of flange portions 21a, 21b are continuous with the outer circumferential surface of the end portion of the base portion 20 on the other axial side.

[0121] The pair of flange portions 21a, 21b are spaced apart in the first direction and disposed approximately parallel to each other. A gap 37 is provided between the inner surfaces of the pair of flange portions 21a, 21b in the first direction. The gap 37 is continuous with the slit 22 in the second direction. The gap 37 has the same size as the width dimension of the slit 22 before the bolt 24 is tightened. The gap 37 can be formed by cutting the slit 22 at the same time as the gap 37 using a cutter, which is a rotary cutting tool.

[0122] The dimension between the outer surfaces of the pair of flange portions 21a, 21b in the first direction is slightly smaller than the dimension between the outer peripheral surfaces 36a, 36b of the first non-interlocking portions 27a, 27b in the first direction before the bolt 24 is tightened.

[0123] The pair of flanges 21a, 21b have mounting holes 23a, 23b on the same axis. 23 The central axis O of the mounting holes 23a and 23b faces the first direction. 23 is the central axis O of the insertion hole 25 25 are arranged in a twisted position.

[0124] In this example, one of the pair of mounting holes 23a, 23b, 23a, is a cylindrical bolt insertion hole, and the other of the pair of mounting holes 23a, 23b, 23b, is a screw hole.

[0125] However, when implementing the present disclosure, the pair of mounting holes may be cylindrical holes, in which case the diameter of the base is reduced by screwing a nut onto the tip of the bolt inserted through the pair of mounting holes.

[0126] The first yoke 17 further includes a connecting portion 38 for connecting to another member in a manner enabling torque transmission.

[0127] In this example, the connecting portion 38 is configured by a pair of arm portions 39a, 39b. The pair of arm portions 39a, 39b each extend in the axial direction and are disposed spaced apart from each other.

[0128] Each of the pair of arm portions 39a, 39b is configured in a substantially plate shape. The pair of arm portions 39a, 39b are disposed adjacent to one axial side of the base portion 20. Base ends of the pair of arm portions 39a, 39b are connected to two radially opposite positions of the end portion on one axial side of the base portion 20.

[0129] In the illustrated example, the pair of arm portions 39a, 39b are spaced apart in the second direction. In other words, the pair of arm portions 39a, 39b are arranged at positions that are shifted in phase with each other by 90 degrees in the circumferential direction with respect to the pair of flange portions 21a, 21b.

[0130] However, when implementing the present disclosure, the pair of arm portions may be disposed spaced apart in the first direction, or may be disposed spaced apart in another direction.

[0131] Of the pair of arm portions 39a, 39b, the phase of one arm portion 39a in the circumferential direction matches the phase of the slit 22 in the circumferential direction.

[0132] In this example, the pair of arms 39 a, 39 b are integrally formed with the base 20 .

[0133] The pair of arms 39a, 39b each have a through hole 40 that is a coaxially arranged through hole. A shaft portion constituting the cross shaft 19 is rotatably supported in the through hole 40 via a bearing cup.

[0134] To fix the first yoke 17 to the end of the pinion shaft 13, as shown in FIG. 12, the end of the pinion shaft 13 is inserted into the insertion hole 25, and the male serration teeth 32 and the female serration teeth 29 are engaged by serration. The bolt 24 inserted through the mounting hole 23a in one flange portion 21a is screwed into the mounting hole 23b in the other flange portion 21b. The bolt 24 is then further tightened to reduce the width of the slit 22 and the gap 37, and the diameter of the base 20 is reduced, so that the end of the pinion shaft 13 is tightened by the base 20. This fixes the first yoke 17 to the end of the pinion shaft 13.

[0135] In this example, when the bolt 24 is tightened and the base 20 is reduced in diameter, a gap 41 exists between the male serration teeth 32 provided on the outer peripheral surface of the pinion shaft 13 and the first toothless portion 30 provided on the inner peripheral surface of the first non-meshing portions 27a, 27b.

[0136] According to the first yoke 17 of this embodiment, the deformation resistance of the base portion 20 when the bolt 24 is tightened can be reduced, and the tightening force can be increased.

[0137] The base 20 of the first yoke 17 in this example has meshing portions 26a to 26c with female serration teeth 29 on the inner peripheral surface, and first non-meshing portions 27a, 27b with no female serration teeth 29 on the inner peripheral surface and with a first toothless portion 30. The first non-meshing portions 27a, 27b have a first toothless portion 30 on the inner peripheral surface that is not provided with the female serration teeth 29. 29 and the outer circumferential surfaces 36a, 36b are located radially outward of the central axis O of the insertion hole 25. 25 A virtual circle S passing through the partially cylindrical outer circumferential surfaces 35a to 35c of the meshing portions 26a to 26c with the center at 26 It is located radially outwardly of the

[0138] Therefore, the meshing portions 26a, 26b and the meshing portions 26a, 26c adjacent in the circumferential direction are arranged such that the inner peripheral surfaces of the meshing portions 26a, 26b and the inner peripheral surfaces of the female serration teeth 29 are spaced apart from each other by a bottom circle S 29 and its outer periphery is a virtual circle S 26 The arc length of the first non-meshing parts 27a, 27b can be made longer than the arc length of the cylindrical part when the first non-meshing parts 27a, 27b are connected by the cylindrical part located above. Therefore, the rigidity of the first non-meshing parts 27a, 27b can be reduced. As a result, the deformation resistance of the base 20 when the bolt 24 is tightened can be reduced, and the tightening force of the first yoke 17 can be increased.

[0139] In this example, the first non-meshing portions 27a, 27b are disposed on both sides of the imaginary plane β. Therefore, the rigidity of the base 20 is reduced equally on both sides of the imaginary plane β. Therefore, the inner peripheral surface of the base 20 can tighten the outer peripheral surface of the end of the pinion shaft 13 in a well-balanced manner.

[0140] The first yoke 17 of this example has reduced deformation resistance when the bolts 24 are tightened, and therefore a sufficient tightening force of the base 20 is ensured. Therefore, even when the first yoke 17 of this example is incorporated into a column-assist steering device 1 to which not only the torque caused by the driver operating the steering wheel 2 but also high assist torque from the electric assist device 9 is transmitted, micro-sliding of the pinion shaft 13 relative to the base 20 is suppressed. This makes it possible to suppress damage such as fretting wear and fretting corrosion from occurring in the female serration teeth 29 and / or the male serration teeth 32.

[0141] In the first yoke 17 of this example, when the bolt 24 is tightened, a gap 41 exists between the male serration teeth 32 provided on the outer peripheral surface of the pinion shaft 13 and the first toothless portions 30 provided on the inner peripheral surfaces of the first non-meshing portions 27a, 27b. This makes it possible to reduce torque loss when the bolt 24 is tightened, and to increase the tightening force applied by the first yoke 17.

[0142] The first yoke 17 of this example has the second toothless portion 31 on the inner peripheral surface of the second non-meshing portion 28, so that when the bolt 24 is tightened, the female serration teeth 29 are strongly pressed against the male serration teeth 32 in the first direction. This is therefore advantageous in terms of transmitting high torque.

[0143] [Example 2] A second example of the embodiment of the present disclosure will be described with reference to FIGS.

[0144] In the base portion 20a of the first yoke 17a of this embodiment, a hollow portion 42 is formed in a first toothless portion 30a which is the inner circumferential surface of the first non-meshing portions 27c and 27d.

[0145] In this example, the hollow portion 42 is formed over the entire axial length of the first toothless portion 30a.

[0146] The first toothless portion 30a is formed with the hollow portion 42, so that the radius of curvature r 27 Radius of curvature r smaller than27a It is composed of a concave curved surface having a shape of (r 27a <r 27 In this example, the first toothless portion 30a is formed by a concave cylindrical surface.

[0147] The thickness of the first non-meshing portions 27c, 27d is smaller than the thickness of the meshing portions 26a to 26c and the second non-meshing portion 28. The thickness of the first non-meshing portions 27c, 27d is smallest at the circumferential center and increases from the circumferential center toward both sides in the circumferential direction.

[0148] The base 20a of the first yoke 17a in this example has a first toothless portion 30a with a cut-out portion 42 formed on the inner circumferential surface of the first non-meshing portions 27c, 27d. This can further reduce the rigidity of the first non-meshing portions 27c, 27d. This can further reduce the deformation resistance of the base 20a when the bolt 24 is tightened, and can further increase the tightening force of the first yoke 17a. In addition, the weight of the first yoke 17a can be reduced compared to when the cut-out portion 42 is not provided.

[0149] The other configurations and effects of the second example are the same as those of the first example.

[0150] [Example 3] A third example of the embodiment of the present disclosure will be described with reference to FIGS.

[0151] In the base portion 20b of the first yoke 17b of the present embodiment, a hollow portion 42 is formed in a part of the first toothless portion 30b which is the inner circumferential surface of the first non-meshing portions 27e, 27f.

[0152] In this example, the removed portion 42 is provided only in a portion of the first toothless portion 30b that axially overlaps with the slit 22. In other words, the removed portion 42 is formed in the other axial half of the inner circumferential surface of the first non-meshing portions 27e, 27f.

[0153] Since the first toothless portion 30b has a hollow portion 42 formed in the other axial half, the radius of curvature changes at the axial center portion.

[0154] In this example, the other axial half of the first tooth-missing portion 30b in which the removed portion 42 is formed is formed by forging, and the one axial half of the first tooth-missing portion 30b in which the removed portion 42 is not formed is formed by broaching together with the female serration teeth 29 and the second tooth-missing portion 31.

[0155] In the present embodiment, the base 20b has the hollowed-out portion 42 only in a portion of the first toothless portion 30b that overlaps with the slit 22 in the axial direction, so that the strength of one axial half of the base 20b can be ensured.

[0156] The other configurations and effects of the third example are the same as those of the first and second examples.

[0157] [Example 4] A fourth example of the embodiment of the present disclosure will be described with reference to FIGS.

[0158] In the first yoke 17c of this embodiment, the pair of flange portions 21c, 21d are separate from the base portion 20c.

[0159] In this example, the pair of flange portions 21c, 21d are provided on a part of the fastening member 43.

[0160] The fastening member 43 has a partially cut cylindrical shape as a whole, and has an end face shape that is substantially U-shaped. The fastening member 43 has a pair of flange portions 21c, 21d and a connecting tube portion .

[0161] The connecting cylinder portion 44 has a substantially semi-cylindrical shape, and connects the pair of flange portions 21c, 21d.

[0162] The fastening member 43 has a fitting hole 45 in a portion surrounded by the pair of flange portions 21c, 21d and the connecting cylinder portion 44. The fitting hole 45 has a shape that matches the outer circumferential surface shape of the other axial end portion of the base portion 20c.

[0163] The fastening member 43 is attached to the base portion 20c by inserting the other axial end of the base portion 20c into the fitting hole 45.

[0164] In the first yoke 17c of the present embodiment, the pair of flange portions 21c, 21d are formed separately from the base portion 20c, so that the manufacturing process of the first yoke 17c can be simplified, and therefore the manufacturing cost of the first yoke 17c can be reduced.

[0165] The other configurations and effects of the fourth example are the same as those of the first example.

[0166] [Example 5] A fifth example of the embodiment of the present disclosure will be described with reference to FIGS.

[0167] This example is an example in which a clamp device according to one aspect of the present disclosure is applied to a connecting device that constitutes an intermediate shaft incorporated in a steering device for an automobile.

[0168] The intermediate shaft 6a of this example constitutes a steering device for a large automobile, and connects the steering shaft and the pinion shaft of a steering gear unit so as to be capable of transmitting torque.

[0169] The intermediate shaft 6 a includes a first shaft 46 , a second shaft 47 , and a coupling device 48 .

[0170] The first shaft 46 is a collapsible shaft, and is configured such that its overall length can be contracted only when an automobile crash occurs and an impact load of a predetermined value or greater is applied to it.

[0171] The second shaft 47 is configured so that its overall length is extendable even in a steady state in which no automobile collision has occurred.

[0172] The first shaft 46 and the second shaft 47 are two rotating shafts that are arranged coaxially and rotate by operating the steering wheel 2 (see FIG. 1).

[0173] The coupling device 48 connects the end of the first shaft 46 and the end of the second shaft 47 in a torque transmissible manner.

[0174] The coupling device 48 has a base 20 and a pair of flange portions 21a, 21b. Unlike the first yoke 17 of the first example, the coupling device 48 of this example does not have a coupling portion. The coupling device 48 of this example has the same configuration as the first yoke 17 of the first example, except that it does not have a pair of arm portions.

[0175] In this example, one axial end of the second shaft 47 is inserted into the inside of an insertion hole 25 (see FIG. 8) provided in the base 20. As a result, the female serration teeth 29 provided on the inner peripheral surface of the base 20 and the male serration teeth 32 (see FIG. 12) provided on the outer peripheral surface of the end of the second shaft 47 are engaged with each other through serrations.

[0176] The other axial end of the first shaft 46 is fitted onto one axial end of the base 20. The one axial end of the base 20 and the other axial end of the first shaft 46 are fixed by welding with a weld bead portion 49.

[0177] The base 20 of the connecting device 48 of this example has meshing portions 26a to 26c having female serration teeth 29 on their inner circumferential surfaces, and first non-meshing portions 27a, 27b having first toothless portions 30 on their inner circumferential surfaces. Of these, the first non-meshing portions 27a, 27b have a first toothless portion 30 on its inner circumferential surface that is located at a depth of 0.05 mm from the bottom circle S of the female serration teeth 29. 29 and the outer circumferential surfaces 36a, 36b are located radially outward of the central axis O of the insertion hole 25. 25 A virtual circle S passing through the partially cylindrical outer circumferential surfaces 35a to 35c of the meshing portions 26a to 26c with the center at 26 Therefore, according to the connecting device 48 of this example, it is possible to reduce the deformation resistance of the base portion 20 when the bolt 24 (see FIG. 3) is tightened, and it is possible to increase the tightening force of the connecting device 48.

[0178] The other configurations and effects of the fifth example are the same as those of the first example.

[0179] Although the first to fifth examples of the embodiment of the present disclosure have been described above, the structures of the first to fifth examples can be appropriately combined and implemented as long as no contradiction occurs. [Explanation of symbols]

[0180] 1 Steering device 2 Steering wheel 3 Steering shaft 4. Steering column 5a, 5b Universal joint 6, 6a Intermediate shaft 7 Steering gear unit 8 Tie Rod 9 Electrically assisted devices 10 Gear housing 11 Torsion bar 12 Output shaft 13 Pinion shaft 14 Torque Sensor 15 Electric motor 16 Worm reducer 17, 17a, 17b, 17c First York 18 Second York 19 Cross axis 20, 20a, 20b, 20c base 21a, 21b, 21c, 21d flange parts 22 Slit 23a, 23b Mounting holes 24 Volts 25 Insertion hole 26a~26c Engagement part 27a~27f 1st non-meshing part 28 Second non-engaging part 29 Female serrated teeth 30, 30a, 30b 1st missing tooth part 31 2nd missing tooth part 32 Male serrated teeth 33 Closed end 34 Open end 35a~35c outer surface 36a, 36b outer surface 37 Gap 38 Connecting part 39a, 39b Arm section 40 through hole 41 Gap 42 Thinning section 43 Fastening member 44 Connecting cylinder part 45 Fitting hole 46 1st Shaft 47 Second Shaft 48 Coupling device 49 Weld bead 100a, 100b York 101a, 101b base 102a, 102b Slits

Claims

1. The device includes a base portion having a generally cylindrical shape and a pair of flange portions. the base portion has an insertion hole extending in an axial direction, a slit disposed at one location in a circumferential direction and extending in the axial direction, an engagement portion having female serration teeth on an inner peripheral surface, and a non-engagement portion having no female serration teeth on an inner peripheral surface, the meshing portion has an outer peripheral surface in a partial cylindrical shape centered on a central axis of the insertion hole, and is provided at three locations on the base, the location being a portion on the radially opposite side of the slit and both sides of a virtual plane including the central axis of the insertion hole and the central axis of the slit; the non-engaging portion has an inner peripheral surface located radially outward of a bottom circle of the female serration teeth of the engaging portion, and an outer peripheral surface located radially outward of an imaginary circle centered on the central axis of the insertion hole and passing through the partially cylindrical outer peripheral surface of the engaging portion, and is provided at two locations on both circumferential sides of the base portion that are located radially opposite the slit, The pair of flange portions have mounting holes on the same axis and are disposed on both sides of the slit in the circumferential direction. Clamping device.

2. The clamp device according to claim 1 , wherein the base portion has a second non-engagement portion, the second non-engagement portion having no female serration teeth on an inner peripheral surface thereof, at a portion spanning the slit in the circumferential direction.

3. The non-engagement portion has a cut-out portion on the inner circumferential surface, The thickness of the removed portion of the non-meshing portion is smaller than the thickness of the meshing portion.

2. The clamping device according to claim 1.

4. The clamp device according to claim 3 , wherein the hollow portion is provided only at a portion that overlaps with the slit in the axial direction.

5. 2. The clamping apparatus of claim 1, wherein said pair of flanges are integral with said base.

6. The clamp device according to claim 1 , further comprising a connecting portion that is connected to another member in a torque-transmittable manner.

7. The clamp device according to claim 6 , wherein the connecting portion is constituted by a pair of arms.

8. 8. The clamp device according to claim 7, wherein one of the pair of arms is disposed at a position where its phase in the circumferential direction coincides with that of the slit.

9. A clamping device according to any one of claims 1 to 8, a rotating shaft that rotates during use and is inserted into the insertion hole; The rotating shaft has male serration teeth on its outer circumferential surface, a gap exists between the male serration teeth and the inner peripheral surface of the non-engagement portion when the rotation shaft is inserted into the insertion hole and the base portion is reduced in diameter; The connection structure between the clamp device and the rotating shaft.

10. Two rotational axes that rotate by operating the steering wheel and are not arranged on the same axis; a universal joint that connects the ends of the two rotating shafts to each other in a torque transmittable manner, The universal joint has a pair of yokes and a cross shaft, At least one of the pair of yokes is the clamp device according to claim 7 or 8. Steering gear.

11. Two coaxially arranged rotating shafts that rotate by operating a steering wheel; A coupling device that connects the ends of the two rotating shafts to each other in a torque-transmittable manner, The connecting device is a clamping device according to any one of claims 1 to 6. Steering gear.

Images