JP5879786B2 - Coupling device - Google Patents

Description

  The present invention relates to a coupling device capable of transmitting a relatively large torque between two rotating shafts arranged substantially coaxially and allowing a slight eccentricity or angular deviation between the rotating shafts. .

  A so-called Oldham coupling as disclosed in Patent Document 1 is widely known as a coupling device that connects two rotating shafts eccentric to each other. This Oldham coupling is configured to absorb the eccentricity of the two rotating shafts by sliding the intermediate member along two diametrical directions intersecting the cross shape, and in principle allows a relatively large eccentricity. Can do.

  On the other hand, in Patent Document 2, in a hybrid vehicle including an internal combustion engine and an electric motor as a vehicle drive source, a rotor of a motor is fixed to the rear end of a crankshaft of the internal combustion engine, and the rotor and a transmission input shaft are connected to each other. A configuration is disclosed in which the drive plates are connected by a drive plate having a truncated cone shape.

JP 2010-249151 A JP 2004-242494 A

  The Oldham coupling as disclosed in Patent Document 1 is not suitable as a coupling device in a portion where torque fluctuation is large, such as an internal combustion engine, because there is a backlash of the sliding portion, and the configuration is complicated and large. And also lubrication problems.

  On the other hand, in the configuration of Patent Document 2, the crankshaft of the internal combustion engine and the transmission input shaft are connected via the rotor of the motor and the frustoconical drive plate. There is no mechanism that allows slight eccentricity or angular deviation between the input shaft and the concentricity of both must be ensured with very high accuracy. And if slight eccentricity etc. remain, since this cannot be absorbed, for example, uneven wear of a bearing will arise.

The present invention is a coupling device that connects a first rotating shaft and a second rotating shaft while allowing an eccentricity or angular deviation of the central axis of the both, and the first rotating shaft is attached to the first rotating shaft. , A second flange that is attached to the second rotating shaft and is disposed to face the first flange, and a plurality of connecting arms. The connecting arm is made of a belt-like metal plate having spring properties, and a plurality of radial arms are provided, one end on the outer peripheral side is fixed to the first flange, and the other end on the inner peripheral side is the second. It is fixed to each flange. The connecting arm is provided with a wave-like bent portion that allows expansion and contraction deformation in the radial direction at the intermediate portion in the radial direction, and is relatively rigid as compared with the end portion on the outer peripheral side and the end portion on the inner peripheral side. Is provided with a low-rigidity portion formed by forming a hole or notch in the metal plate constituting the connecting arm so as to reduce the thickness or partially reducing the plate thickness .

  In such a coupling device, rotation is transmitted from one rotating shaft to the other rotating shaft through a plurality of radially arranged connecting arms. The individual connecting arms can be elastically deformed by the spring property of the metal plate. For example, the center axis of the second rotating shaft is eccentric with respect to the center axis of the first rotating shaft, or the center axes of the two rotating shafts are angled. Even when they are displaced, the eccentricity and angular deviation are absorbed by the elastic deformation of each connecting arm, and rotational torque can be transmitted. The connecting arm that extends radially generally tends to concentrate stress on the attachment portions at both ends fixed to the first and second flanges, but the stress is dispersed by providing a low-rigidity portion in the middle portion in the radial direction. As a result, stress concentration in the mounting portion is alleviated.

  According to the present invention, rotation can be transmitted while allowing the eccentricity and angular deviation of the two rotating shafts with a relatively simple configuration, and there is no problem of backlash due to torque fluctuation and the need for lubrication. .

The principal part sectional drawing of the Example provided with the coupling apparatus which concerns on this invention between the crankshaft of an internal combustion engine, and the electric motor. Sectional drawing which shows the coupling apparatus of this Example alone. The top view which similarly looked at the coupling apparatus of the Example from the electric motor side. The top view which shows one of the connection arms provided with the slit. Sectional drawing of the principal part which shows an example of a wavelike bending part. Sectional drawing of the principal part which shows the other example of a wavelike bending part. Sectional drawing of the principal part which shows the other example of a wavelike bending part. Explanatory drawing which shows the deformation | transformation state of a connection arm in case the motor rotating shaft is eccentric with respect to a crankshaft. Explanatory drawing which shows the deformation | transformation state of a connection arm in case transmission torque is large. The top view of the 2nd Example which provided the notch in the connection arm.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a configuration of a connecting portion between an internal combustion engine 2 and an electric motor 3 as one example in which the coupling device 1 according to the present invention is used. In the internal combustion engine 2, a crankshaft 5 is rotatably supported via a main bearing (not shown) below the cylinder block 4, and a crank chamber 6 in which the crankshaft 5 is accommodated is defined. An oil pan 7 is attached to the lower surface of the cylinder block 4.

  A transmission housing 11 is attached to a rear end surface of the internal combustion engine 2 including the oil pan 7 and the cylinder block 4, and the electric motor 3 is accommodated in a front end portion of the transmission housing 11. A transmission gear mechanism (not shown) is accommodated in the rear portion of the transmission housing 11. The electric motor 3 includes a stator 12 fixed to the transmission housing 11 side, and a rotor 13 that rotates with respect to the stator 12. The rotor 13 is fixed to a motor rotating shaft 14, and the front end portion of the motor rotating shaft 14 is rotatably supported by a bulkhead portion 15 at the front end of the transmission housing 11 via a bearing 16 and is an oil seal. 17 is sealed.

  The motor rotating shaft 14 is arranged in series with respect to the crankshaft 5 of the internal combustion engine 2 and they are basically arranged so as to be concentric with each other. The rear end of the crankshaft 5 and the front end of the motor rotating shaft 14 are connected via the coupling device 1 in order to absorb slight eccentricity and angular misalignment of both central axes that may be caused by time errors. Has been. The rear end portion of the crankshaft 5 is sealed to the cylinder block 4 and the oil pan 7 on the rear end surface of the internal combustion engine 2 via an oil seal (not shown).

  The transmission housing 11 has a bell mouth portion 18 that gradually swells to a large diameter in front of the bulkhead portion 15, and the coupling device 1 having a disc shape as a whole is provided in the bell mouth portion 18. The space is accommodated in a space generated between the bulkhead portion 15 of the transmission housing 11 and the rear end surface of the internal combustion engine 2.

  As shown in FIGS. 2 and 3, the coupling device 1 is generally composed of a first flange plate 21, a second flange plate 22, and a plurality of connecting arms 23 that connect the two.

  The first flange plate 21 is formed by press-molding a steel plate. The first flange plate 21 has a circular shape as a whole, and a small-diameter reinforcing plate 24 is stacked on the center and fixed by a rivet 25. Is attached to a boss portion 27 at the rear end of the crankshaft 5 by a plurality of bolts 26. The first flange plate 21 is formed in a shape in which the central portion is slightly recessed toward the internal combustion engine 2 with the position slightly on the outer peripheral side of the outer peripheral edge of the reinforcing plate 24 as a boundary. Plates 24 are stacked. Further, an annular ring member 28 serving as a weight for a flywheel is attached to the outer peripheral portion of the first flange plate 21 by a bolt 29 on the surface on the internal combustion engine 2 side. Furthermore, the outer peripheral edge of the first flange plate 21 is bent rearward in the axial direction, that is, along the cylindrical surface, and a large number of tooth portions 30 are notched. In the transmission housing 11, a probe (not shown) for detecting the tooth portion 30 is disposed adjacent to the tooth portion 30, and the rotation position (of the crankshaft 5 ( A crank angle sensor for detecting (crank angle) is configured. That is, the first flange plate 21 also functions as a so-called signal plate of the crank angle sensor. In other words, the signal plate normally disposed at the rear end of the crankshaft 5 also serves as the first flange plate 21. It has become.

  The second flange plate 22 is made of a die-cast part such as an aluminum alloy. The second flange plate 22 has a smaller diameter than the first flange plate 21, and a cylindrical portion 31 is integrally formed at the center. The tip of the motor rotating shaft 14 is splined or serrated, and the tip of the motor rotating shaft 14 is fitted to the inner peripheral surface of the cylindrical portion 31 having the corresponding spline or serration. The second flange plate 22 is located opposite to the first flange plate 21, and an appropriate interval is maintained between them in the axial direction. More specifically, the cylindrical portion 31 has a major portion protruding in the axial direction from the surface of the second flange plate 22 to the front (that is, the internal combustion engine 2 side), and the tip of the cylindrical portion 31 is the first flange. The interval is set so that the plate 21 is positioned slightly behind the reinforcing plate 24. The second flange plate 22 is provided with a plurality of circular openings 32 corresponding to the positions of the bolts 26 for attachment to the crankshaft 5.

  The first flange plate 21 and the second flange plate 22 are connected to each other by a plurality of, for example, seven connecting arms 23 in this embodiment. The connecting arm 23 is made of a steel plate having spring properties. As shown in FIG. 4, as shown in FIG. 4, the arc-shaped outer peripheral rim portion 41 along the outer peripheral edge of the first flange plate 21 and the outer side of the second flange plate 22. An arcuate inner peripheral rim portion 42 extending along the periphery and an arm portion 43 having a band shape with a certain width connecting the two are formed, and as a whole, I-shaped or T-shaped. Mounting holes 44 are provided at both ends of the outer peripheral rim portion 41, and the outer peripheral rim portion 41 is fixed to the outer peripheral portion of the first flange plate 21 by bolts 29 penetrating through the mounting holes 44. The bolt 29 is screwed into the ring member 28, and simultaneously connects the ring member 28 disposed on the front surface of the first flange plate 21 and the outer peripheral rim portion 41 disposed on the rear surface of the first flange plate 21. It is fixed to the first flange plate 21. A pair of mounting holes 45 are provided in the inner peripheral rim portion 42, and the inner peripheral rim portion 42 is fixed to the front surface of the outer peripheral portion of the second flange plate 22 by a rivet 46 that passes through these mounting holes 45. ing. Thus, in a state where the connecting arms 23 are respectively attached, the respective arm portions 43 extend radially along the radial lines of the first flange plate 21 and the second flange plate 22. A plurality of, for example, seven, connecting arms 23 are arranged at equal intervals along the circumferential direction.

  As shown in FIGS. 1 and 2, the arm portion 43 of the connecting arm 23 is inclined in the axial direction so as to connect the outer peripheral rim portion 41 and the inner peripheral rim portion 42 that are located apart from each other in the axial direction. However, in the coupling device 1 of the embodiment, a wave-like bent portion 47 that allows expansion and contraction deformation in the radial direction is provided in the intermediate portion in the radial direction.

  The wavy bent portion 47 is configured by bending the arm portion 43 made of a band-shaped metal plate once or a plurality of times in a circular arc shape or a substantially U shape in cross section. 5 to 7 show several examples of the wave-like bent portion 47. In the example of FIG. 5, the arm portion 43 has a cross-sectional arc along a folding line indicated by reference numeral 51 near the outer rim portion 41. In addition to being bent into a shape, it is configured to be bent into a circular arc shape in the opposite direction along a folding line indicated by reference numeral 52 near the inner peripheral rim portion 42. In other words, the two bent portions are loose. It has an arc-shaped step shape. The folding lines 51 and 52 form a straight line along the tangential direction of rotation on the plan view as shown in FIG.

  In the example of FIG. 6, the arm portion 43 is folded into a cross-sectional arc shape along a folding line indicated by reference numeral 53 near the outer peripheral rim portion 41, and is folded back into a substantially U-shaped cross section along a ridge line indicated by reference numeral 54. In this configuration, it is bent into a circular arc shape along a folding line indicated by reference numeral 55 near the inner peripheral rim portion 42. In other words, between the outer peripheral rim portion 41 and the inner peripheral rim portion 42, a mountain portion 56 having a substantially U-shaped cross section protruding toward the rear (the electric motor 3 side) is provided. The folding lines 53 and 55 and the ridge line 54 form a straight line along the tangential direction of rotation.

  In the example of FIG. 7, the arm portion 43 is folded in a cross-sectional arc shape along a folding line indicated by reference numeral 57 near the outer peripheral rim portion 41, and is folded back in a substantially U-shaped cross section along a ridge line indicated by reference numeral 58. In this configuration, it is folded back into a substantially U-shaped cross-section in the reverse direction along the ridge line indicated by reference numeral 59, and is further bent in a cross-section arc shape along a folding line indicated by reference numeral 60 near the inner peripheral rim portion 42. . In other words, between the outer peripheral rim portion 41 and the inner peripheral rim portion 42, a substantially U-shaped cross-section 61 projecting rearward (to the electric motor 3 side), and conversely a substantially concave U-section. And a trough portion 62 having a character shape. The folding lines 57 and 60 and the ridges 58 and 59 form a straight line along the tangential direction of rotation.

The coupling device 1 of the embodiment shown in FIGS. 1 to 4 includes a wave-like bent portion 47 similar to that of the example shown in FIG. 7, and is a valley recessed opposite to the peak portion 61 protruding rearward. Part 62. However, in this example, as shown in FIGS. 1 and 2, the radii of the bent portions corresponding to the folding lines 57 and 60 in FIG. 7 are relatively small, and from the outer peripheral rim portion 41 and the inner peripheral rim portion 42. The intermediate arm portion 43 is bent substantially linearly .

  Further, an elongated slit 70 is formed in an intermediate portion in the radial direction of the arm portion 43 so as to constitute a low-rigidity portion having relatively low rigidity compared to both end portions of the arm portion 43. . This slit 70 extends along the tangential direction of rotation, and is formed in the central portion of the width of the arm portion 43 so as to leave only both side portions of the arm portion 43 made of a band-shaped metal plate. It should be noted that one or more circular holes may be formed side by side or a plurality of short slits may be formed in place of the formation of one elongated slit 70 as described above.

  In the embodiment shown in FIGS. 1 to 4, the slit 70 is formed to avoid the peaks 61 and valleys 62 of the wave-like bent portion 47 that is displaced in the bending direction, but the present invention is not limited to this. For example, in the example of FIG. 6, the slit 70 is located near the top of the peak portion 56.

  In the coupling device 1 configured as described above, rotational torque is transmitted between the first flange plate 21 and the second flange plate 22 through the plurality of radially arranged arm portions 43. And since the 2nd flange plate 22 is hold | maintained with respect to the 1st flange plate 21 via the arm part 43 which can be elastically deformed, relative eccentricity and angle shift | offset | difference of both center axis lines are accept | permitted. FIG. 8 schematically shows, as an example, the state of each connecting arm 23 when the center axis of the second flange plate 22 is eccentric to the right with respect to the center axis of the first flange plate 21. As described above, according to the eccentricity of the second flange plate 22, the arm part 43 located on the left side of the figure expands and the arm part 43 located on the right side of the figure shrinks, thereby easily absorbing the eccentricity. That is, it is possible to reliably transmit rotational torque while allowing eccentricity of the central axis. Similarly, angular deviations between the two central axes are also absorbed. In particular, in this embodiment, since the wavy bent portion 47 that can be expanded and contracted is provided, eccentricity and angular deviation are more easily absorbed.

  Here, if there is an eccentricity as described above, a part of the arm portions 43 (for example, the arm portions 43 positioned above and below in FIG. 8) are inclined with respect to the radial line, and the arm portions 43 and the outer periphery are inclined. Stress tends to concentrate on the corner of the connecting portion with the side rim portion 41 and further on the corner of the connecting portion between the arm portion 43 and the inner peripheral rim portion 42. On the other hand, in the above-described embodiment, the intermediate portion in the radial direction of the arm portion 43 has low rigidity due to the formation of the slit 70, so that stress is dispersed and stress concentration in the corner portions at both ends of the arm portion 43 is alleviated. The Therefore, high durability can be obtained.

  In FIG. 8, for the sake of explanation, the second flange plate 22 is depicted as being largely decentered. However, as described above, the crankshaft 5 of the internal combustion engine 2 and the motor rotation shaft 14 of the electric motor 3 are basically the same. Since they are arranged concentrically, the amount of eccentricity and angular deviation to be absorbed by the coupling device 1 are actually very small values. For example, it is sufficient to absorb an eccentricity of 1 mm or less and an angular deviation of 1 degree or less.

  FIG. 9 shows a slightly exaggerated view of the deformation state of each connecting arm 23 when a large rotational torque is applied between the first flange plate 21 and the second flange plate 22. In this example, the second flange plate 22 rotates in the clockwise direction with respect to the first flange plate 21, and accordingly, each connecting arm 23 is inclined so as to be inclined with respect to the radial line. In such a case, the intermediate arm portion 43 tends to incline with respect to the outer peripheral rim portion 41 and the inner peripheral rim portion 42. Therefore, if the entire arm portion 43 has a certain rigidity, the arm portion 43 The stress is concentrated at the corner of the connection portion between the outer peripheral rim portion 41 and the corner of the connection portion between the arm portion 43 and the inner peripheral rim portion 42. On the other hand, in the above embodiment, as in the example of FIG. 8, the stress is dispersed by the slit 70 in the intermediate portion, and the stress concentration in the corner portions at both ends of the arm portion 43 is alleviated.

  Note that the position, size, and the like of the slit 70 are set so that the stress distribution in each part in the deformed state as shown in FIGS. 8 and 9 is appropriate.

  As described above, according to the coupling device 1 described above, the crankshaft 5 of the internal combustion engine 2 and the motor rotating shaft 14 of the electric motor 3 can be connected in a form that allows some eccentricity or angular deviation between them. It is possible to easily absorb the tolerance of each part and the error when the transmission housing 11 is attached. Since the coupling device 1 has a small axial dimension and can be accommodated in a space in the bell mouth portion 18 between the internal combustion engine 2 and the electric motor 3, the internal combustion engine 2 and the electric motor arranged in series. There is no need to enlarge the overall axial dimension with 3. In particular, the first flange plate 21 also serves as a signal plate for the crank angle sensor, so that the number of parts as a whole is reduced and the coupling device 1 is accommodated in a space necessary for arranging a normal signal plate. Is possible. Moreover, the coupling device 1 does not require lubrication and can secure sufficient durability.

  Further, the first flange plate 21 connected to the internal combustion engine 2 side is substantially a rigid body, and the flywheel is constituted by the weight of the outer peripheral portion, that is, the ring member 28. Therefore, the internal combustion engine that acts on the connecting arm 23. 2 is suppressed, and the durability of the coupling device 1 can be increased from this point.

  Next, FIG. 10 shows a second embodiment in which notches 71 are provided on both side edges of the connecting arm 23 as a low-rigidity portion of the connecting arm 23 instead of forming the slit 70 described above. That is, the connecting arm 23 of this embodiment is roughly divided into an outer peripheral rim portion 41, an inner peripheral rim portion 42, and an arm portion 43, and a pair of notches are provided in the middle portion of the arm portion 43 in the radial direction. 71 is provided so that a narrow narrow portion 72 remains.

  The narrow portion 72 has lower rigidity than both end portions of the arm portion 43 connected to the outer peripheral rim portion 41 and the inner peripheral rim portion 42, and therefore, stress is dispersed as in the above-described embodiment. The position and size of the narrow portion 72 are set so that the stress distribution of each portion in the deformed state is appropriate.

  In addition, as the low-rigidity portion, a configuration in which rigidity is lowered by partially reducing the thickness of the intermediate portion in the radial direction of the arm portion 43 is also possible.

  In each of the above embodiments, the plurality of connecting arms 23 are separately formed and individually attached to the first and second flange plates 21 and 22, but the outer peripheral rim 41 and the inner peripheral rim 42 It is also possible to form a plurality of connecting arms 23 as one member, assuming that at least one is continuous in an annular shape. Further, in the illustrated example, the arm portion 43 is disposed completely along the radial line of the first and second flange plates 21, 22, but may be disposed to be inclined in consideration of the rotational direction, for example. Furthermore, the 1st flange plate 21 and the 2nd flange plate 22 do not necessarily need to be circular, and should just be a shape which can attach the connection arm 23 radially.

  The coupling device of the present invention is not limited to the power transmission between the internal combustion engine 2 and the electric motor 3 described above, and can be widely applied to connection of rotating shafts in various drive mechanisms and rotating devices.

DESCRIPTION OF SYMBOLS 1 ... Coupling apparatus 2 ... Internal combustion engine 3 ... Electric motor 5 ... Crankshaft 14 ... Motor rotating shaft 21 ... 1st flange plate 22 ... 2nd flange plate 23 ... Connection arm 30 ... Tooth part 41 ... Outer peripheral side rim part 42 ... Inner peripheral side rim part 43 ... arm part 47 ... wavy bent part
70 ... Slit 71 ... Notch

Claims (5)

A coupling device that connects the first rotating shaft and the second rotating shaft while allowing eccentricity or angular deviation of the central axis of the two,
A first flange attached to the first rotating shaft;
A second flange attached to the second rotating shaft and disposed opposite to the first flange;
It consists of a strip-shaped metal plate having spring properties, and a plurality of radial metal plates are arranged, one end on the outer peripheral side is fixed to the first flange, and the other end on the inner peripheral side is fixed to the second flange. A plurality of connected arms,
The connecting arm includes a wavy bent portion that allows expansion and contraction deformation in the radial direction at the intermediate portion in the radial direction, and relatively relative to the end portion on the outer peripheral side and the end portion on the inner peripheral side. rigid coupling device, characterized in that it comprises a low rigidity portion formed by thinning the formation or thickness hole or notch of the metal plate constituting the connecting arms partially to be lower. The coupling device according to claim 1 , wherein the hole is a slit elongated along a tangential direction of rotation. Provided between the internal combustion engine and the motor arranged in series, to claim 1 or 2, connected to the first crankshaft axis of rotation and comprising an internal combustion engine and a rotating shaft of the motor to be the second rotary shaft The coupling device as described. The coupling according to any one of claims 1 to 3 , wherein the first rotation shaft is an input shaft, and the first flange is configured as a flywheel having a weight on an outer peripheral portion. apparatus. The connecting arm has an outer peripheral rim portion that forms an arc along the outer peripheral edge of the first flange, and an inner peripheral rim portion that forms an arc along the outer peripheral edge of the second flange. and, to any one of claims 1 to 4, the outer peripheral side rim portion, characterized in that said inner circumferential rim portion is fixed to the second flange together are fixed to the first flange The coupling device as described.

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