JP6227448B2 - Resonator - Google Patents

Description

  The present invention relates to a resonator that is arranged in an air chamber between a tire and a wheel to which the tire is attached to reduce noise.

  Conventionally, for a wheel in which a rubber tire is mounted on a metal wheel, random vibration transmitted from the road surface to the tire vibrates air in the air chamber between the wheel and the tire, and near the air column resonance frequency of the air chamber. There is a known phenomenon in which a resonance phenomenon (cavity resonance) is generated and noise called air column resonance is generated. And in order to reduce this noise, the sub air chamber which communicates with an air chamber via a cylindrical communication part is divided inside, and the resonator (resonator) which functions as a Helmholtz resonance sound absorber by the communication part and the sub air chamber There is.

  Such a resonator is generally manufactured by blow molding. That is, by sandwiching the molten resin supplied from the die between the molds and blowing the air into the mold using blow pins, the molten resin is brought into close contact with the cavity, thereby forming the resonator body that partitions the sub air chamber inside. The both side portions sandwiched between the molding dies serve as plate-like locking portions that are locked to the holding portions facing the rim surface of the wheel (see, for example, Patent Document 1).

  In the case of this resonator, since it is locked to the wheel by the plate-like locking portions located on both sides, for example, the plate thickness is increased so that the locking can be reliably maintained against the centrifugal force during traveling. There is a need. In addition, since the mating surface of the mold, that is, the parting surface is located at the tip of the locking part, burrs are generated at the tip of the locking part. It is necessary to remove the burrs with high accuracy in advance and to perform dimension inspection and the like before the attachment.

  In this respect, the locking portions extending on both sides of the resonator main body are made hollow so as to define a part of the auxiliary air chamber, thereby improving the strength of the locking portion and improving the parting surface of the molding die. A configuration is known in which a high-precision removal operation and dimensional inspection operation of burrs are reduced and manufacturing costs are suppressed by setting the position so as not to contact the holding portion of the locking portion (for example, see Patent Document 2). .

  However, in the case of this resonator, since the strength is improved by making the locking portion hollow, the locking portion is not easily deformed when press-fitted between the holding portions, and a large force is required for mounting.

JP 2010-149363 A (page 4-6, FIG. 1-4) JP 2012-45971 A (Page 4, FIGS. 7-9)

  As described above, there is a demand for a resonator that can be easily attached to the wheel and can be reliably locked while suppressing the manufacturing cost.

  The present invention has been made in view of the above points, and an object thereof is to provide a resonator that can be attached to a wheel with good workability and can be reliably locked to the wheel while suppressing the manufacturing cost. And

The resonator according to claim 1, wherein the resonator is disposed in an air chamber between a tire and a wheel to which the tire is attached to reduce noise, and has a longitudinal direction along a circumferential direction of the wheel. A resonator main body provided with a sub air chamber therein, and a communication portion provided in the resonator main body for communicating the sub air chamber with the air chamber, the resonator main body facing the rim surface of the wheel. A bottom plate portion, an upper plate portion spaced away from the rim surface with respect to the bottom plate portion, and the bottom plate portion and the upper plate portion are connected to each other at both sides, and the sub plate portion and the upper plate portion together with the sub plate portion and the upper plate portion. A locking portion that divides the air chamber and extends to both sides and is locked to a holding portion facing the rim surface, and a recess provided on at least one side of the bottom plate portion , the communication unit, the resonator present Of at least one of the ends of the longitudinal direction, the part with respect to the upper plate portion is provided along the longitudinal direction so as to be substantially flush, the bottom plate portion and the upper plate portion except the recess In this position, blow molding is performed using a mold having a parting surface along the longitudinal direction of the resonator body.

  According to a second aspect of the present invention, in the resonator according to the first aspect, a plurality of recesses are provided intermittently in the longitudinal direction along a direction intersecting with the longitudinal direction of the resonator body.

  According to a third aspect of the present invention, in the resonator according to the second aspect, the locking portion is provided at a position shifted from the concave portion in the longitudinal direction of the resonator main body.

Resonator of 請 Motomeko 4 described in claims 1 to 3 resonator of any one described, the upper plate portion and the continuous resonator body part over substantially flush of communicating portion with respect to the upper plate portion Grooves are provided along the longitudinal direction.

According to the resonator of claim 1, the parting surface is formed by blow molding using a mold having a parting surface along the longitudinal direction of the resonator main body at the position of the bottom plate portion and the upper plate portion excluding the concave portion. The formed burrs are not formed on the engaging portions extending on both sides of the bottom plate portion and the upper plate portion, and a high-precision removal step and dimensional inspection step of the burrs are not required, and the manufacturing cost can be suppressed. Since the concave portion is provided on at least one of the side portions of the bottom plate portion, it is possible to suppress the engagement of the bottom plate portion to the holding portion when attaching between the holding portions, and the workability of attachment to the wheel is improved. Since the locking portion is a hollow shape that divides the auxiliary air chamber together with the bottom plate portion and the upper plate portion, the strength can be secured and the locking portion can be reliably locked to the wheel holding portion . At least one end in the longitudinal direction of the resonator main body is provided with a communication portion along the longitudinal direction so that a part thereof is substantially flush with the upper plate portion, so that the centrifugal force generated by the rotation of the wheel is generated. Water that has been effectively utilized and has entered the auxiliary air chamber can be reliably discharged to the air chamber along the upper plate portion via the communicating portion .

  According to the resonator according to claim 2, in addition to the effect of the resonator according to claim 1, by providing a plurality of recesses intermittently in the longitudinal direction along the direction intersecting the longitudinal direction of the resonator main body, Thus, the surface rigidity of the bottom plate portion can be improved. Therefore, for example, even when traveling at high speed, the wheel can be reliably locked in a stable state.

  According to the resonator of the third aspect, in addition to the effect of the resonator of the second aspect, the locking portion is provided at a position shifted from the concave portion in the longitudinal direction of the resonator main body, so that the thin wall at the position of the locking portion is provided. Can be more reliably suppressed, and can be more reliably locked to the wheel by the locking portion.

According to the resonator of 請 Motomeko 4, in addition to claims 1 to 3 Effect of the resonator of any one described, over the upper plate portion and the communicating portion part is substantially flush with respect to the upper plate portion By providing continuous grooves along the longitudinal direction of the resonator body, water that has entered the secondary air chamber is collected more effectively using the centrifugal force generated by the rotation of the wheel, and the communication section is connected along the upper plate. It can be reliably discharged to the air chamber via

BRIEF DESCRIPTION OF THE DRAWINGS The 1st related technique of the resonator of this invention is shown, (a) is a perspective view which shows a resonator from upper direction, (b) is a perspective view which shows a resonator from the downward direction. It is sectional drawing which expands and shows a part of resonator same as the above. It is sectional drawing which shows the attachment operation | work to the wheel of a resonator same as the above in order of (a) (b). It is explanatory drawing which shows typically the formation procedure of a resonator same as the above in order of (a) thru | or (e). It is a perspective view which shows the wheel which attached the resonator same as the above. It is a perspective view which shows the 2nd related technique of the resonator of this invention. It is a perspective view which shows the 3rd related technique of the resonator of this invention. 1 is a perspective view showing a first embodiment of a resonator according to the present invention. (A) is the cross-sectional view of FIG. 8, (b) is the longitudinal cross-sectional view of FIG. It is sectional drawing which shows 2nd Embodiment of the resonator of this invention.

The first related art of the resonator of the present invention will be described below with reference to the drawings.

  1 to 5, reference numeral 10 denotes a wheel device. The wheel device 10 is also called a resonator wheel including a metal wheel 11 and, for example, a plurality of resonators 12 attached to the wheel 11 in the circumferential direction. The wheel of an automobile is configured by attaching a rubber tire (not shown) to the wheel device 10.

  The wheel 11 includes a rim portion 16, a hub portion (not shown) located inside the rim portion 16, and a disk portion 18 that connects the rim portion 16 and the hub portion. The rim portion 16 is provided with a bead seat portion (not shown) formed along both end portions in the width direction of the wheel 11, and further projecting outward from the outer end side of the bead seat portion in the radial direction of the wheel 11. A rim flange portion (not shown) and a well portion 23 which is located between the bead seat portions and is recessed toward the inner side in the radial direction of the wheel 11 are provided. By mounting the bead portion of the tire on the bead seat portion, an air chamber 25 having a predetermined volume, which is an annular sealed space, is configured by being surrounded by the rim portion 16 of the wheel 11 and the tire. The well portion 23 of the rim portion 16 is provided for temporarily dropping the bead portion of the tire when the tire is assembled to the rim portion 16. Each resonator 12 is attached to the rim surface 26 that is the bottom of the well portion 23.

  Then, on the rim surface 26 of the well portion 23, side surfaces 28 and 28 as side holding surfaces are raised along the radial direction of the wheel 11, and the resonator is attached by the side surfaces 28 and 28 and the rim surface 26. A mounting groove 29 as a portion is formed. At the upper ends of the side surfaces 28, 28, holding portions 33, 33 that are folded back so as to face the rim surface 26 are provided so as to be continuous over the entire circumference of the wheel 11, for example. That is, the holding portions 33 and 33 are located above the rim surface 26 at a position separated from the rim surface 26.

  Each resonator 12 can also be called a wheel resonator, and includes a resonator main body 36 that is integrally molded by blow molding using a synthetic resin and curved in an arc shape, and a communication portion 37 that protrudes from the resonator main body 36. It has a cylindrical shape as a whole, is curved along a predetermined arc, and is symmetrical with respect to both sides.

  The resonator body 36 is formed in a longitudinal shape having a longitudinal direction along the circumferential direction of the wheel 11. The resonator main body 36 has a bottom plate portion 41 that faces the rim surface 26 so as to face the rim surface 26, and an upper plate portion 42 that is spaced above and opposite the bottom plate portion 41 (on the side of the rim surface 26). An engaging portion 43 that connects both side portions of the bottom plate portion 41 and the upper plate portion 42 along the longitudinal direction, and a connecting portion 44 that connects both end portions of the bottom plate portion 41 and the upper plate portion 42 in the longitudinal direction. The bottom plate portion 41, the upper plate portion 42, the locking portions 43, and the connecting portions 44 form a hollow shape that divides the auxiliary air chamber 45 therein. Each of the locking portions 43 is held by each holding portion 33 and the entire resonator 12 is accommodated in the mounting groove 29, whereby the resonator 12 is fixed to the wheel 11. Hereinafter, the longitudinal direction refers to the longitudinal direction of the resonator body 36, and the both-side direction (short direction) refers to the direction orthogonal to the longitudinal direction of the resonator body 36.

  The bottom plate portion 41 is formed so as to be gently curved (not sharply bent) in a U shape so that a cross section perpendicular to the longitudinal direction bulges downward toward the rim surface 26 as a whole. Yes. The bottom plate portion 41 gradually protrudes downward from the side portions 41a and 41a toward the central portion 41b, and the curvature of the side portions 41a and 41a is larger than the curvature of the central portion 41b. The bottom plate portion 41 is formed wider than the upper plate portion 42, and both side portions 41a and 41a protrude laterally with respect to the upper plate portion 42. Further, a plurality of recesses 47, 47 are provided intermittently in the longitudinal direction on both side portions 41a, 41a of the bottom plate portion 41 along a direction intersecting (orthogonal) with the longitudinal direction. That is, in each side portion 41a of the bottom plate portion 41, the concave portions 47 and the non-concave portions 48 are alternately arranged at substantially equal intervals in the longitudinal direction.

  Each concave portion 47 includes an upper curved portion 47a as a first curved surface portion whose upper end portion is continuous with the lower end portion of each locking portion 43, and a second curved surface portion that is gently continuous with the lower end portion of the upper curved portion 47a. And a lower curved portion 47b as a single unit. And the recessed parts 47 and 47 located in the both sides 41a and 41a of the baseplate part 41 are the positions which mutually oppose in a both-sides direction, ie, the position which substantially corresponds to a longitudinal direction.

  The upper curved portion 47a is curved so as to enter the lower side, which is the back side of the locking portion 43, when viewed in the cross section in both side directions. That is, the upper curved portion 47a is curved so as to incline downward toward the rim surface 26 toward the central portion in both side directions. Further, the upper curved portion 47a is formed so as to form a part of a curved surface that bulges upward in a convex shape, and the bending direction is opposite to that of the lower curved portion 47b. Therefore, each concave portion 47 is formed so as to be gradually deeper from the upper end portion and the lower end portion toward the continuous portion of the upper curved portion 47a and the lower curved portion 47b with respect to the bottom plate portion 41 (side portion 41a). Has been.

  The lower curved portion 47b is curved in a U shape so as to bulge downward toward the rim surface 26 so as to continue smoothly toward the central portion 41b of the bottom plate portion 41. The lower curved portion 47b is formed along, for example, an arc centered on the opposite locking portion 43, and has a larger curvature (a smaller radius of curvature) than both side portions 41a and 41a of the bottom plate portion 41. Yes.

  The upper plate portion 42 is formed in a curved shape in an inverted U shape so that a cross section perpendicular to the longitudinal direction bulges upward upward, which is opposite to the rim surface 26 as a whole. That is, the upper plate portion 42 gradually protrudes upward from the side portions 42a and 42a toward the central portion 42b, and the curvature of the side portions 42a and 42a is larger than the curvature of the central portion 42b.

Each locking portion 43 extends laterally from the bottom plate portion 41 and the upper plate portion 42 and is formed in a longitudinal shape that is continuous in the longitudinal direction along both side portions of the resonator main body 36 in this related technology . These locking portions 43 are a vertical wall portion 43a as a first wall portion continuous with the bottom plate portion 41 and the concave portion 47, and a second wall portion as a second wall portion continuous with the vertical wall portion 43a and the upper plate portion 42. And a horizontal wall 43b which is a contact surface. The horizontal wall 43b of each locking portion 43 abuts on the back side of each holding portion 33, that is, the lower surface facing the rim surface 26, so that the resonator 12 is prevented from coming off upward and locked between the holding portions 33. It has come to be.

  Each vertical wall portion 43a constitutes the outermost side portion of each locking portion 43, and is a portion facing and spaced apart from each side surface 28 with the resonator 12 attached to the wheel 11. These vertical wall parts 43a are continuous with the horizontal wall part 43b through the upper connecting part 43c as the first connecting part whose upper end part is curved in an arc shape in a cross section orthogonal to the longitudinal direction, and the lower end part is A lower connection as a second connection portion that is gently continuous with the side portion 41a of the bottom plate portion 41 and has a cross section orthogonal to the longitudinal direction curved in an arc shape with respect to the upper curved portion 47a of each recess 47 It is continuous via the part 43d. The vertical dimension L1 of these vertical wall portions 43a is set to the maximum possible dimension in order to ensure the rigidity of each locking portion 43.

  The upper connecting portion 43c is formed to have the smallest possible radius considering the amount of lap with the holding portion 33 of the wheel 11.

  The lower connecting portion 43d is formed to have the maximum possible radius in order to improve the attachment property (assembly property) to the wheel 11. Therefore, the lower connecting portion 43d has a curved surface shape having a larger radial dimension than the upper connecting portion 43c.

  Each horizontal wall portion 43b constitutes the uppermost portion of each locking portion 43, and intersects (orthogonal) the longitudinal direction, that is, has a planar shape along a direction substantially parallel to the rim surface 26. . These horizontal wall portions 43b have outer end portions that are continuous with the upper end portions of the vertical wall portions 43a via the upper connecting portions 43c, and inner end portions that are longitudinal with respect to the side portions 42a of the upper plate portion 42. The cross sections orthogonal to each other are continuous via an inner connecting portion 43e as a third connecting portion curved in an arc shape. The projecting dimension L2, which is the short dimension of the horizontal wall part 43b, is formed to the minimum required dimension considering the wrapping allowance and clearance with each holding part 33, and is continuous with the upper plate part 42 of each locking part 43. The shape undulation on the upper side is made gentle.

  The inner connecting portion 43e is formed to the maximum possible deformation corresponding to the radial dimension of the upper connecting portion 43c, and the upper shape undulation continuous with the upper plate portion 42 of the locking portion 43 is made gentle. The inner connecting portion 43e has a curved surface shape having a larger radial dimension than the lower connecting portion 43d and the upper connecting portion 43c.

  Each connecting portion 44 connects the bottom plate portion 41 and the upper plate portion 42 in a planar shape at both ends in the longitudinal direction and closes both ends of the auxiliary air chamber 45.

  The auxiliary air chamber 45 is also referred to as a hollow portion, and is a space having a longitudinal direction along the circumferential direction of the wheel 11. Further, the auxiliary air chamber 45 does not include a passage communicating with the outside other than the communication portion 37.

  The communication portion 37 communicates the auxiliary air chamber 45 with the air chamber 25, has a cylindrical shape, and protrudes upward at, for example, the central portion of the upper plate portion 42 of the resonator main body 36 in the longitudinal direction and both side directions. .

  Then, with the air chamber 25 as the main air chamber, the capacity (volume) of the sub air chamber 45, the length of the communication portion 37, and the like are set so as to satisfy the following equations for obtaining the resonance frequency of the Helmholtz resonance sound absorber.

fo = C / 2π × √ (S / V (L + α × √S))
fo [Hz]: resonance frequency of the air chamber 25 C [m / s]: sound velocity inside the air chamber 25 S [m ² ]: cross-sectional area of the communication part 37 of the resonator 12 V [m ³ ]: sub-air of the resonator 12 Capacity of chamber 45 L [m]: Length of communication portion 37 of resonator 12 α: Correction coefficient

  The resonance frequency fo is set in accordance with the resonance frequency of the air chamber 25. For the plurality of resonators 12 provided in the air chamber 25, all the resonators 12 are set to the same setting. When a plurality of resonance frequencies are recognized, the length and the cross-sectional area of the communication portion 37 communicating with each sub air chamber 45 may be different, or the average value of the plurality of resonance frequencies of the air chamber 25 may be obtained. Can also be set.

The resonator 12 is manufactured by blow molding in this related technology . In this blow molding, the molds 51 and 52 (one and the other) shown in FIG. 4 are used. The molds 51 and 52 are planar (one and other) parting surfaces 51a and 52a that are brought into contact with each other in a closed mold state, and (one and other) molding surfaces 51b and 52b that form an outer shell of the resonator 12. A cavity 53, which is a space in which the parison P that is a molten resin is accommodated, is defined between the molding surfaces 51b and 52b in a state where the parting surfaces 51a and 52a are abutted with each other. . Further, the parting surface 51a of the mold 51 and 52, 52a is shaped surfaces 51b, 52 b position corresponding to the bottom plate portion 41 and the upper plate portion 42 excluding the recessed portion 47, 47, in the related art, the forming surface 51b , 52b and the positions corresponding to the center portions 41b, 42b of the upper plate portion 42, that is, the positions separated from the locking portions 43, 43. For this reason, these molds 51 and 52 are substantially line-symmetric with each other in both directions of the resonator 12 at the parting surfaces 51a and 52a.

Then, for example, the parison P is set in the cavity 53 by closing the molds 51 and 52 with respect to the cylindrical parison P (FIG. 4A) supplied from above to below by a die (not shown) (FIG. 4). 4 (b)). At this time, part of the parison P is sandwiched between the parting surfaces 51 a and 52 a of the molds 51 and 52. Subsequently, when the compressed air A is injected and injected into the inside of the parison P in the cavity 53 via a blow pin (not shown) (FIG. 4C), the parison P in the cavity 53 swells and the molds 51 and 52 are formed. Are pressed into close contact with the molding surfaces 51b and 52b (FIG. 4D). At this time, the parison P is sequentially brought into close contact with the molding surfaces 51b and 52b so as to be separated from both sides from the center of the cavity 53, that is, the positions of the parting surfaces 51a and 52a in this related technology . Therefore, in the resonator 12, the parison P is thickest at the positions of the central portions 41b and 42b of the bottom plate portion 41 and the upper plate portion 42, and the parison is located at the positions of the locking portions 43 and 43 farthest from the central portion of the cavity 53. P becomes the most stretched thin wall state.

  The locking portions 43 and 43 and the surrounding shaping when viewed in a cross section in both directions will be described in more detail. At the positions of the non-recessed portions 48 of the both side portions 41a and 41a of the bottom plate portion 41, the gentle inclination After the parison P is in close contact with the molding surfaces 51b and 52b sequentially toward the vertical wall 43a of the locking portions 43 and 43 along the (curved surface), the upper connecting portion is connected to the vertical wall 43a of each locking portion 43. Close contact toward 43c from below. Further, at the positions of the respective concave portions 47 of the both side portions 41a and 41a of the bottom plate portion 41, the parison P extends from the lower curved portion 47b to the upper curved portion 47a along the gentle slope (curved surface) of the locking portions 43 and 43. After being in close contact with the molding surfaces 51b and 52b sequentially toward the vertical wall 43a, it is in close contact with the vertical wall 43a of each locking portion 43 from the lower connecting portion 43d to the upper connecting portion 43c from below. At this time, the lower connecting portion 43d is curved to the maximum possible radius, and the vertical dimension L1 of the vertical wall portion 43a is a planar shape having the maximum possible dimension, so that it is relatively narrowed vertically by the recess 47 in particular. Even at the position, the parison P securely adheres to the molding surfaces 51b and 52b. On the other hand, at the positions of both side portions 42a and 42a of the upper plate portion 42, the parison P sequentially contacts the molding surfaces 51b and 52b toward the lateral wall portion 43b of the locking portions 43 and 43 along the gentle slope (curved surface). After that, the parison P is in close contact with the molding surfaces 51b and 52b so that the parison P is extended along the horizontal wall portion 43b from the inner coupling portion 43e toward the upper coupling portion 43c. At this time, the inner connecting portion 43e is curved to the maximum possible radius and the projecting dimension L2 of the lateral wall portion 43b is the minimum necessary, so the shape undulation is gentle, so the parison along the molding surfaces 51b and 52b. P is reliably stretched and a local thin portion is not easily formed, and is securely in contact with the molding surfaces 51b and 52b without causing a hole or the like.

  Thereafter, the parison P in close contact with the molding surfaces 51b and 52b is cooled and cured, so that the hollow intermediate body M is shaped in a predetermined shape. Then, the intermediate body M is removed from the molds 51 and 52 by opening the molds 51 and 52 (FIG. 4E), and the tip of the communication part 37 is calculated by a predetermined length calculated based on the above resonance frequency equation. The resonator 12 is completed by cutting the burrs and removing the burrs B which are unnecessary portions. Since the position of the burr B is separated from the locking parts 43 and 43 that are locked and held by the holding parts 33 and 33 when the resonator 12 is assembled to the wheel 11, the removal work of the burr B is more than necessary. It becomes a simple one that does not require accuracy.

  When assembling the resonator 12 to the wheel 11, first, the resonator 12 is inserted into the mounting groove 29 from the one locking portion 43 in an inclined manner with respect to the mounting groove 29 of the wheel 11. The tip of the portion 43 is brought into contact with one holding portion 33 (FIG. 3A). Next, using the one locking portion 43 in contact with the one holding portion 33 as a fulcrum, the bottom plate portion 41 of the resonator 12 is slid on the other holding portion 33 using a jig or the like (not shown) while the other engagement portion 43 is engaged. The stopper 43 is pushed downward into the mounting groove 29 so as to rotate along the direction indicated by the arrow X (FIG. 3B). At this time, the concave portion 47 on the back side of the other locking portion 43 of the bottom plate portion 41 facing the other holding portion 33 has a size that does not interfere with the other holding portion 33 (one locking portion 43 And the lower connecting portion 43d in which the other locking portion 43 and the recess 47 are continuous is seen in a cross section in both directions. Since the curved surface has the maximum possible radius, the contact (sliding) area between the gently curved bottom plate portion 41 and the other holding portion 33 is reduced, and the other locking portion 43 can be moved with a relatively small insertion force. It can be easily locked to the other holding portion 33. As a result, each of the resonators 12 comes off with respect to the radial direction of the wheel 11 by the locking portions 43 and 43 coming into contact with the holding portions 33 and 33 and the central portion 41b of the bottom plate portion 41 coming into contact with the rim surface 26. Stopped and held. In this state, each resonator 12 is attached to the wheel 11 with the longitudinal direction along the circumferential direction of the wheel 11 and with both side directions perpendicular to the longitudinal direction along the width direction of the wheel 11.

  A tire (not shown) is attached to the wheel 11 to which the resonator 12 is attached, so that an air chamber 25 is defined between the wheel 11 and the tire, and the auxiliary air chamber 45 of each resonator 12 is provided in the air chamber 25. Communicate with each other via the communication part 37. Therefore, each resonator 12 functions as a Helmholtz resonance sound absorber, which effectively contributes to the air column resonance generated by the vibration of the air in the air chamber 25 caused by the random vibration transmitted from the road surface to the tire, which contributes to in-vehicle noise. To reduce.

As described above, according to this related technique , the molds 51 and 52 having the parting surfaces 51a and 52a along the longitudinal direction of the resonator main body 36 are used at the positions of the bottom plate portion 41 and the upper plate portion 42 excluding the recess 47. By blowing the resonator 12 in this way, the burrs B formed on the parting surfaces 51a, 52a are not formed on the locking portions 43, 43 extending on both sides of the bottom plate portion 41 and the upper plate portion 42, A high-precision removal process of burrs, a dimension inspection process, and the like are not required, and thus manufacturing costs can be reduced, such as shortening of manufacturing tact and no need to create jigs and inspection tools.

In addition, since the concave portion 47 is provided in at least one of the side portions 41a of the bottom plate portion 41, and both side portions 41a and 41a in this related technology , the holding portion of the bottom plate portion 41 when the resonator 12 is attached between the holding portions 33 and 33. The engagement to 33 and 33 (contact area) can be suppressed, and the workability of attachment to the wheel 11 is improved. Furthermore, since the locking portions 43 and 43 are hollow so as to define the auxiliary air chamber 45 together with the bottom plate portion 41 and the upper plate portion 42, the strength can be ensured as compared with a simple plate-shaped locking portion, and the wheel 11 can be held. It can be securely locked to the parts 33, 33.

  In addition, by providing a plurality of recesses 47 intermittently in the longitudinal direction along the direction intersecting with the longitudinal direction of the resonator body 36, the recess 47 functions as a reinforcing bead and a bottom plate portion that contacts the rim surface 26 Since the central portion 41b of 41 is a position corresponding to the parting surfaces 51a and 52a of the molds 51 and 52, it is thicker than the other portions, so that it becomes a pseudo bead, and the bottom plate portion 41 Since the side portions 41a and 41a that are continuous with the locking portions 43 and 43 have gentle slopes (curved surfaces), the surface rigidity of the bottom plate portion 41 can be improved, such as prevention of thinning during molding. Therefore, for example, the resonator 12 can be reliably locked to the wheel 11 in a stable state even during high-speed traveling. Further, when the resonator 12 is press-fitted into the wheel 11 and attached, the bottom plate portion 41 is not deformed.

  In particular, each locking portion 43 has a vertical dimension L1 of the vertical wall portion 43a that is the largest possible plane, thereby improving transferability to the molds 51 and 52, and each locking size with the intended product dimensions. The portion 43 can be formed, the protruding dimension L2 of the lateral wall portion 43b is minimized, and the lower connecting portion 43d and the inner connecting portion 43e are each formed as a curved surface having the maximum possible radius when viewed in cross section on both sides. By making the undulations gentle, it is possible to mold the resonator 12 that has sufficient rigidity to be prevented from being deformed by press fitting at the time of being attached to the wheel 11, such as suppressing local thinning during molding.

  Furthermore, by making the resonator 12 line symmetrical in both directions, the product stability after mounting on the wheel 11 is improved, and the centrifugal force acting on the resonator 12 is equally applied to both sides even during high-speed driving. , Rattling, etc. can be reliably prevented.

In the first related art described above, as in the second related art shown in FIG. 6, the locking portion 43 is moved in the longitudinal direction of the resonator main body 36 at both side portions 41 a and 41 a of the bottom plate portion 41 of the resonator main body 36. May be provided at positions shifted from the recesses 47 and intermittently arranged in the longitudinal direction. In this case, thinning at the positions of the locking portions 43 and 43 can be more reliably suppressed, and the resonator 12 can be locked to the wheel 11 more reliably by the locking portions 43 and 43.

Further, as in the third related technique shown in FIG. 7, the locking portion 43 may be further thinned out in the longitudinal direction. That is, the pitch and number of the locking portions 43 can be set as appropriate as long as there is no functional problem.

Further, when the tire is filled with air using an air compressor or the like, moisture is filled simultaneously with the air, and in some cases, moisture may be accumulated in the auxiliary air chamber 45. Therefore, as in the first embodiment shown in FIGS. 8 and 9, at least one end in the longitudinal direction of the resonator main body 36, in this embodiment, one connecting portion 44 is rotated by the rotation of the wheel 11. The communication part 37 may be provided along the longitudinal direction so that the upper part is substantially flush with the upper plate part 42 to which the centrifugal force is applied most. At this time, the upper plate portion 42 and a groove portion 55 that continues to the upper plate portion 42 over the communication portion 37 that is substantially flush with the upper plate portion 42 are provided in the central portion 42b along the longitudinal direction of the resonator body 36, and It is preferable that the plate portion 42 has an inverted V shape that is inclined toward the groove portion 55 (upward) from both side portions 42a, 42a to the central portion 42b. That is, the communication portion 37 is formed so as to communicate with the position of the resonator body 36 that protrudes in the radial direction of the wheel 11 to the maximum, and the groove portion 55 of the resonator 12 from the rim surface 26 to the radial direction of the wheel 11 is formed. It is preferable to form it at the farthest position.

  In this case, due to the centrifugal force generated by the rotation of the wheel 11, moisture inside the auxiliary air chamber 45 adheres to the upper plate portion 42, and along the slopes of both side portions 42a, 42a of the upper plate portion 42, Centrifugal force is surely concentrated on the groove portion 55 of the central portion 42b where it acts most, and is discharged from the communication portion 37 to the air chamber 25 via the groove portion 55, for example, when decelerating during running or braking. That is, the moisture that has entered the auxiliary air chamber 45 by effectively utilizing the centrifugal force can be reliably discharged along the upper plate portion 42 to the air chamber 25 via the communication portion 37. As a result, moisture does not accumulate in the auxiliary air chamber 45, the resonance frequency of the resonator 12 set as a function of the capacity of the auxiliary air chamber 45 is stabilized, and stable sound absorbing performance can be exhibited.

  In addition, since the communication portion 37 is disposed in the mounting groove 29 and does not face the tire, the communication portion 37 is not accidentally damaged when the tire is attached or detached.

Further, the first embodiment described above may be combined with the second related technique or the third related technique .

In order to more reliably prevent deformation when press-fitting into the wheel 11 and assembling, the concave portion 47 is formed on one side portion 41a of the bottom plate portion 41, for example, as in the second embodiment shown in FIG. The parting surfaces 51a and 52a of the molds 51 and 52 are provided only on the side 41a on the side opposite to the recess 47 in the bottom plate 41 and on one side in the upper plate 42. You may make it shift to 41a side, respectively. In this case, the position in the vicinity of the thickest parting surfaces 51a and 52a is the other side portion 41a side of the bottom plate portion 41 in contact with the rim surface 26, and one of the locking portions 43 to be press-fitted. Can be made closer to the parting surfaces 51a and 52a and thicker than the other locking portion 43, and sufficient rigidity can be secured for press-fitting into the wheel 11 for assembly. However, the parting surfaces 51a and 52a are positioned within the range of the bottom plate portion 41 excluding the concave portion 47 and the top plate portion 42 so that burrs at the time of molding are not formed in the locking portions 43 and 43. Within range .

  The present invention can be applied to a resonator that is arranged in an air chamber of a wheel of an automobile or the like to reduce noise caused by resonance.

11 wheel
12 Resonator
25 Air chamber
26 Rim surface
33 Holding part
36 Resonator body
37 Communication part
41 Bottom plate
42 Upper plate
43 Locking part
45 Secondary air chamber
47 recess
51, 52 Mold
51a, 52a Parting surface
55 Groove

Claims (4)

A resonator that is arranged in an air chamber between a tire and a wheel to which the tire is attached to reduce noise,
A resonator body having a longitudinal direction along the circumferential direction of the wheel, and having a sub air chamber therein,
Provided in the resonator main body, comprising a communication portion for communicating the auxiliary air chamber with the air chamber,
The resonator body is
A bottom plate portion facing the rim surface of the wheel;
An upper plate portion spaced apart from the rim surface with respect to the bottom plate portion;
The bottom plate portion and the upper plate portion are connected at both sides to partition the auxiliary air chamber together with the bottom plate portion and the upper plate portion, and are extended to both sides and locked to the holding portion facing the rim surface. A locking portion to be
A recess provided on at least one side of the bottom plate portion,
The communication part is provided along the longitudinal direction at least at one end in the longitudinal direction of the resonator body so that a part thereof is substantially flush with the upper plate part,
A resonator that is blow-molded using a molding die having a parting surface along the longitudinal direction of the resonator main body at the position of the bottom plate portion and the upper plate portion excluding the concave portion. The resonator according to claim 1, wherein a plurality of recesses are provided intermittently in the longitudinal direction along a direction intersecting with the longitudinal direction of the resonator body. The resonator according to claim 2, wherein the locking portion is provided at a position shifted from the concave portion in the longitudinal direction of the resonator main body . The upper plate portion and a communication portion that is partially flush with the upper plate portion and continuing to the longitudinal direction of the resonator main body are provided along the longitudinal direction of the resonator body . The resonator according to one .

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