JP4737429B2 - Sensor plate - Google Patents

Description

  The present invention relates to a sensor plate used in combination with a sensor for detecting the rotational speed of a rotating shaft such as a crankshaft of an automobile engine. The sensor plate of the present invention is, for example, a torque fluctuation absorbing damper that absorbs fluctuations in torque transmitted from a drive shaft to another rotating device in an automobile engine or the like and absorbs resonance of the drive shaft main body, or a torsional damper that absorbs crank resonance. It is also used in fields having other engine / transmission torque mechanisms.

  Conventionally, a sensor plate that is used in combination with a sensor to detect the rotation speed of a crankshaft of an automobile engine is known. As shown in FIG. 6, the sensor plate 51 includes a damper mass 53 of a torsional damper 52. A flange surface 55 is integrally formed at one axial end of the cylindrical portion 54 attached to the inner peripheral surface, and a sensing portion 56 such as a notch is provided at the outer peripheral end of the flange surface 55.

  However, in the conventional sensor plate 51, since the flange surface 55 has a solid shape with no openings, the flange surface 55 is axially caused by plate resonance caused by the vibration input of the crankshaft. And a problem of radiating sound (noise) toward the engine front space S has occurred.

Japanese Patent Laid-Open No. 10-141441 Japanese Utility Model Publication No. 7-18049 Japanese Utility Model Publication No. 7-19649

  An object of this invention is to provide the sensor plate which can reduce the noise which generate | occur | produces in view of the above point.

In order to achieve the above object, a sensor plate according to claim 1 of the present invention is a sensor plate that is mounted on a rotating part such as a damper hub or a damper mass and rotates together with the rotating part, and is provided with a sensing portion on a flange surface. In the sensor plate, a required number of openings are provided in the flange surface in order to reduce the acoustic radiation area on the flange surface, and the opening is formed in a long hole shape in the circumferential direction. The shape is characterized in that the radial width at the center in the circumferential direction is relatively small and the radial width at both ends in the circumferential direction is relatively large .

If the required number of openings are provided in the flange surface to reduce the acoustic radiation area on the flange surface, as in the sensor plate of the present invention having the above-described configuration, the acoustic radiation area is reduced, and this is generated accordingly. Noise can be reduced. Further, since the sensor plate is reduced in weight, it is possible to reduce the loss of rotational torque .

  Since the sensor plate receives a large centrifugal force as the engine rotates at a high speed, it is necessary to provide sufficient strength in the radial direction. Therefore, as described above, it is effective to reduce the acoustic radiation area by opening the flange surface for acoustic reflection from the sensor plate. However, it may be difficult to provide a large opening because it is necessary to provide anti-centrifugal strength.

Therefore, when it is necessary to impart anti-centrifugal strength to the sensor plate in this way, the opening is formed into a long hole shape in the circumferential direction, and the beam shape on the outer periphery side of the opening is formed at the center in the circumferential direction. A shape having a relatively small radial width and a relatively large radial width at both circumferential ends .

  The beam provided on the outer periphery of the long hole-shaped opening is subjected to centrifugal force due to its own weight, but only its own weight acts on its center in the circumferential direction, so the centrifugal force is small, and as it goes to both ends Since the gravity centrifugal force of the component from the central part to both ends acts as a load, a large stress is generated at both ends compared to the central part. Therefore, in the present invention, by having the beam shape appropriate for the stress caused by the centrifugal force, it is possible to equalize the stress at the both ends of the opening by relaxing the stress.

  As described above, if the beam shape on the outer peripheral side of the elongated hole-shaped opening is a shape having a small radial width at the circumferential central portion and a large radial width at both circumferential ends, the beam portion as a whole It has an arch shape. The slope gradient from the center to both ends of the arch-shaped beam portion is most efficiently set according to the following equation in accordance with the diameter of the sensing portion, the inner diameter of the sensor plate, the long side size of the long hole, and the like.

ｔ：円周方向中央部の径方向幅（アーチ中央部高さ）
ｔ’：円周方向端部の径方向幅（アーチ端部高さ）
Ｌ：円周方向中央部から円周方向端部までの距離（アーチ中央から端部までの距離）

t: Radial width at the center in the circumferential direction (arch center height)
t ′: radial width of the circumferential end (arch end height)
L: Distance from the circumferential center to the circumferential edge (distance from the arch center to the edge)

  When the gradient ratio is smaller than 1/10, there is a possibility that the stress at both ends becomes large and breaks. When the gradient ratio is larger than 1/3, the area of the opening is small and weight reduction cannot be realized.

  Although the above calculation formula is a linear linear expression, it is defined by this calculation formula when linear approximation by the least square method or the like is performed even when the partial gradient shape is curved to form a non-linear shape (higher order expression). The present invention is also applicable to the case where the gradient ratio is obtained.

  The present invention has the following effects.

That is, in the sensor plate of the present invention, as described above, since the required number of openings are provided in the flange surface to reduce the acoustic radiation area on the flange surface, the generated noise is reduced as the acoustic radiation area is reduced. Can be reduced. Further, since the sensor plate is reduced in weight, loss of rotational torque can be reduced, and fuel consumption can be improved.

In addition to this, in the sensor plate of the present invention, as described above, since the equalization of the beam shape provided on the outer peripheral side of the elongated hole-shaped opening is realized, sufficient centrifugal resistance for the beam shape is achieved. Strength can be given.

The present invention includes the following embodiments.
That is, in the present invention, an elongated hole opening is provided on the sensor plate flange surface to reduce the acoustic radiation area. The outer peripheral shape of the elongated hole opening portion is provided with a sensing portion having an arch shape in which the height of the opening center portion is thin and the height of both ends of the opening is thickened.

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a torsional damper 1 equipped with a sensor plate 9 according to an embodiment of the present invention. FIG. 2 is an enlarged sectional view taken along line AA in FIG.

  The torsional damper 1 is formed by connecting a damper mass (also simply referred to as mass or mass body or inertial mass body) 7 via a damper rubber (also simply referred to as rubber) 6 to the outer peripheral side of a damper hub (also simply referred to as hub) 2. A sensor plate 9 is mounted on the damper hub 2, a sensing portion 12 is provided on the flange surface 11 of the sensor plate 9, and a required number of openings 13 are formed on the flange surface 11 in order to reduce the acoustic radiation area on the flange surface 11. Is provided.

  The damper hub 2 is formed by integrally forming an outer peripheral cylindrical portion 5 with a boss portion 3 fixed to an end portion of the crankshaft via a radial rising portion 4, and is disposed on the outer peripheral cylindrical portion 5 and the outer peripheral side thereof. A damper rubber 6 is press-fitted from one axial direction into an annular gap between the damper mass 7 and the rubber fitting type torsional damper 1. A pulley groove 8 is provided on the outer peripheral surface of the damper mass 7 for winding an endless belt that transmits rotational torque to other rotating devices such as auxiliary machines.

  The sensor plate 9 is formed by integrally forming a flange surface 11 radially outward at one end in the axial direction of a cylindrical portion 10 fitted to the inner peripheral surface of the outer peripheral cylindrical portion 5 of the damper hub 2. A sensing portion 12 made up of a large number of notches is provided at the outer peripheral end of the surface 11, and a plurality of openings 13 (six locations in the figure) are provided in a uniform manner in the plane of the flange surface 11. The sensing unit 12 including a large number of notches detects the number of rotations of the crankshaft and the like in combination with an optical sensor.

  As shown in an enlarged view in FIG. 3A, each of the openings 13 is formed in a long hole shape that is long in the circumferential direction of the sensor plate 9. Further, the beam portion 14 set on the outer peripheral side of the opening portion 13 has a relatively small radial width t at the circumferential central portion 14a and a relatively large radial width t ′ at both circumferential end portions 14b. It is formed in an arch shape and is set so as to satisfy the following equation.

ｔ：円周方向中央部の径方向幅（アーチ中央部高さ）
ｔ’：円周方向端部の径方向幅（アーチ端部高さ）
Ｌ：円周方向中央部から円周方向端部までの距離（アーチ中央から端部までの距離）

t: Radial width at the center in the circumferential direction (arch center height)
t ′: radial width of the circumferential end (arch end height)
L: Distance from the circumferential center to the circumferential edge (distance from the arch center to the edge)

  Further, the radial width of the beam portion 14 is set so as to gradually increase from the circumferential central portion 14a to both circumferential end portions 14b.

As described above, when the sensor plate 9 rotates, the beam portion 14 provided on the outer peripheral side of the elongated hole-like opening portion 13 receives a centrifugal force due to its own weight, but as shown in FIGS. 4 (A) and 4 (B). As shown in the comparison diagram, when the shape of the beam portion 14 has a constant radial width t _{0 over} the entire length in the circumferential direction, a large stress is generated at both circumferential end portions 14b, resulting in stress concentration. As a result, the beam portion 14 may be damaged due to insufficient strength. On the other hand, in the sensor plate 9, since the beam portion 14 has an arch shape as described above, the stress generated as shown in FIG. 3B is equalized and stress concentration does not occur. Therefore, it is possible to prevent the beam portion 14 from being damaged.

  Returning to the description of FIG. 1, a small opening 15 made of a relatively small circular hole is provided between the long hole-shaped openings 13 arranged in the circumferential direction. And are arranged alternately on the circumference. The small opening 15 has a balance hole function that balances (rotates in a balanced manner) the sensor plate 9 on the circumference, and this also contributes to the reduction of the acoustic radiation area on the flange surface 11.

  In the sensor plate 9 having the above configuration, as described above, since the required number of openings 13 are provided in the flange surface 11 in order to reduce the acoustic radiation area on the flange surface 11, the acoustic radiation area is reduced. The generated noise can be reduced. Moreover, since the sensor plate 9 is reduced in weight, loss of rotational torque can be reduced and fuel consumption can be improved. Moreover, since equalization of the beam portion 14 provided on the outer peripheral side of the elongated hole-shaped opening portion 13 is realized, the beam portion 14 can be provided with sufficient strength against centrifugal force.

  In the above embodiment, the torsional damper 1 to which the sensor plate 9 is mounted is a rubber fitting type torsional damper, but the type is not limited at all, and may be, for example, a bush type torsional damper. . Moreover, in the said Example, although the sensor plate 9 was mounted | worn with the damper hub 2, you may decide to mount | wear with the damper mass 7 like FIG. 6 which concerns on a prior art example. Further, the other party to be mounted is not limited to the torsional damper, and may be a torque fluctuation absorbing damper, for example.

  FIG. 5 shows an example of the torque fluctuation absorbing damper 21, which is configured as follows.

  That is, first, a sensor plate 23 is fitted to the outer peripheral surface of the damper hub 22, and a vulcanized molded product comprising the mounting ring 24, the damper rubber 25 and the first damper mass 26 is fitted to the sensor plate 23, A vulcanized molded product composed of an attachment ring 27, a coupling rubber 28 and a pulley 29 is fitted to one damper mass 26, and a second damper mass 30 is fitted. Since the first damper mass 26 has an outer peripheral cylindrical portion 31 disposed on the outer peripheral side of the coupling rubber 28 and on the inner peripheral side of the pulley 29, a radial is provided between the outer peripheral cylindrical portion 31 and the pulley 29. A bearing 32 is interposed. Since the pulley 29 has an inward flange portion 33 to which the coupling rubber 28 is vulcanized and bonded to the second damper mass 30 in the axial direction, the pulley 29 is provided between the flange portion 33 and the second damper mass 30. A thrust bearing 34 is interposed therebetween. The pulley 29 and the second damper mass 30 are provided with a stopper mechanism 35 that restricts the relative displacement in the circumferential direction of both parts to a certain amount.

  The torque fluctuation absorbing damper 21 configured as described above reduces vibration due to torsional resonance of the rotating shaft by the operation of the dynamic damper part constituted by each component, and reduces vibration transmission due to torque fluctuation during rotation by the operation of the coupling rubber part. The sensor plate 23, which is one of the components, has the opening 36 and the beam portion 37 having the same configuration as in the above-described embodiment, so that the generated noise is reduced and the beam portion is reduced. 37 can have sufficient centrifugal strength. Therefore, the torque fluctuation absorbing damper 21 can also provide the same operational effects as the above embodiment.

1 is a front view of a torsional damper equipped with a sensor plate according to an embodiment of the present invention. FIG. 2 is a half sectional view of the torsional damper, taken along the line AA in FIG. (A) is an enlarged view of the main part of the sensor plate, (B) is a schematic diagram thereof. (A) is the principal part front view of the sensor plate which concerns on a comparative example, (B) is the schematic diagram 1 is a half sectional view of a torque fluctuation absorbing damper equipped with a sensor plate according to an embodiment of the present invention. Half cut section of a torsional damper equipped with a sensor plate according to a conventional example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Torsional damper 2,22 Damper hub 3 Boss part 4 Radial direction rising part 5,31 Outer cylinder part 6,25 Damper rubber 7,26,30 Damper mass 8 Pulley groove 9,23 Sensor plate 10 Cylindrical part 11 Flange surface 12 Sensing part 13, 36 Opening 14, 37 Beam 15 Small opening 21 Torque fluctuation absorbing damper 24, 27 Mounting ring 28 Coupling rubber 29 Pulley 32, 34 Bearing 33 Flange 35 Stopper mechanism

Claims (1)

A sensor plate that is mounted on a rotating component such as a damper hub or a damper mass and rotates together with the rotating component, wherein the sensor plate has a sensing portion on the flange surface.
Provide the required number of openings in the flange surface to reduce the acoustic radiation area on the flange surface ,
The opening has a long hole shape that is long in the circumferential direction, and the beam shape on the outer periphery side of the opening has a relatively small radial width at the center in the circumferential direction and radial widths at both ends in the circumferential direction. A sensor plate characterized by a relatively large shape .

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