JP2005180661A - Tensioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure of stable behavior even when high rotation is input from an engine. <P>SOLUTION: A first shaft member 3 and a second shaft member 4 engaged with each other by screw parts 8, 9, and a torsion spring 5 for rotating and energizing the first shaft member 3 in one direction are accommodated in a case 2, the rotation of the second shaft member 4 is restricted, and the rotational energizing force of the torsion spring 5 is converted into propulsive force of the second shaft member 4. An elastic member 20 for energizing the first shaft member 3 in the axial direction is mounted to bring a shaft end part 3f of the first shaft member 3 into closely contact with the case 2, and supporting members 25, 27 for supporting the first shaft member 3 at least at two points in the axial direction are mounted in the case 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a tensioner that maintains a constant tension of an endless belt or chain.

  The tensioner, for example, pushes a timing chain or timing belt used in an automobile engine with a predetermined force, and acts to keep the tension constant when the chain is stretched or loosened.

  FIG. 12 shows a state in which the tensioner 100 is mounted on the engine body 200 of the automobile. A pair of cam sprockets 210 and 210 and a crank sprocket 220 are arranged inside the engine body 200, and a timing chain 230 is stretched between the sprockets 210, 210 and 220 in an endless manner. Yes. A chain guide 240 is swingably disposed on the moving path of the timing chain 230, and the timing chain 230 slides on the chain guide 240. An attachment surface 250 is formed on the engine body 200, and the tensioner 100 is fixed to the attachment surface 250 by a bolt 270 that passes through the attachment hole 260 of the attachment surface 250. It should be noted that lubricating oil (not shown) is enclosed in the engine body 200.

  FIG. 13 shows a tensioner 100 that is generally used, and a rotating shaft 120 and a propulsion shaft 130 are assembled and disposed inside the case 110. The case 110 has a main body portion 111 extending in the axial direction for inserting the shafts 120 and 130, and a flange portion 112 extending from the main body portion 111 in a direction crossing the axial direction. The flange portion 112 attaches the tensioner 100 to the engine main body 200. For this reason, the flange portion 112 is formed with an attachment hole 113 through which a bolt screwed into the engine main body 200 passes. The main body 111 accommodates each component to be described later. For this reason, a housing hole 114 having the same diameter is formed along the axial direction.

  The rotation shaft 120 and the propulsion shaft 130 are assembled by forming a male screw portion 121 on the outer surface of the rotation shaft 120 and forming a female screw portion 131 on the inner surface of the propulsion shaft 130 and screwing these screw portions 121 and 131 together. Is done by. A receiving seat 140 is provided inside the case 110 corresponding to the proximal end of the rotating shaft 120 so as to be positioned in the storage hole 114, and the receiving shaft 140 allows the proximal end of the rotating shaft 120 to be located. Is supported. In the assembled state, the propulsion shaft 130 is screwed into a substantially half portion on the front side of the rotary shaft 120, and a torsion spring 150 is disposed in a substantially half portion on the rear side where the propulsion shaft 130 is not screwed.

  The torsion spring 150 has a hook portion 151 at one end inserted into a slit 123 formed at the base end portion of the rotary shaft 120 and locked therein, and a hook portion 152 at the other end locked in the case 110. Therefore, when the torsion spring 150 is twisted and assembled with a predetermined torque applied, the rotating shaft 120 is rotated by the urging force of the torsion spring 150.

  A bearing 160 is fixed to the front end portion of the case 110 by a retaining ring 170, and the propulsion shaft 130 passes through the sliding hole 161 of the bearing 160. The inner surface of the sliding hole 161 of the bearing 160 and the outer surface of the propulsion shaft 130 are formed in a substantially oval shape, a parallel cut, or other non-circular shape, whereby the propulsion shaft 130 is in a state in which rotation is restricted. .

  The bearing 160 is formed into a flat plate shape having a predetermined thickness, and a plurality of fixed pieces 162 are formed on the outer peripheral side. The fixed piece 162 is fitted into a notch groove 115 formed at the tip of the case 110, so that the entire bearing 160 is prevented from rotating. Since the bearing 160 is thus prevented from rotating with respect to the case 110, the propulsion shaft 130 penetrating the bearing 160 is rotationally restrained by the case 110 via the bearing 160. The case 110 moves forward and backward.

  A cap 180 is attached to the tip of the propulsion shaft 130, and the cap 180 is in contact with the chain guide 240 in the engine main body 200 described above.

  Further, a spacer 190 is disposed inside the case 110. The spacer 190 has a cylindrical shape extending in the axial direction (propulsion direction) in a state of surrounding the periphery of the rotary shaft 120 and the propulsion shaft 130, and the shafts 120, 130 in the screwed state come out from the tip portion of the case 110. To prevent that. In order to prevent this from coming off, the rotary shaft 120 is formed into a hooked shape that can be abutted against the spacer 190.

  In the tensioner 100 having the above-described structure, the rotating shaft 120 is rotated by the urging force of the torsion spring 150, and this rotating force is converted into the propulsive force of the propulsion shaft 130, so the propulsion shaft 130 advances. As a result, the propulsion shaft 130 presses the timing chain 230 via the cap 180 and the chain guide 240, so that tension can be applied to the timing chain 230.

  However, in the tensioner 100 shown in FIG. 13, when a large external load is input from the timing chain, the input load cannot be handled, and the propulsion shaft 130 is easily pushed.

Japanese Unexamined Patent Application Publication No. 2003-184968 discloses a conventional tensioner that can flexibly cope with such an input load. This tensioner has a basic structure shown in FIG. 13 and a coil spring further incorporated in the structure shown in FIG. The coil spring is disposed between the rotation shaft 120 and the propulsion shaft 130. By arranging the coil spring in this manner, the coil spring generates a resistance torque with respect to the input external load, so that the propulsion shaft is not pushed in, and the external input load is excellent. It is possible to respond.
JP 2003-184968 A

  Even in the tensioner disclosed in Japanese Patent Application Laid-Open No. 2003-184968, when the engine rotates at a high speed and high vibrations are input or lateral vibrations occur, the propulsion shaft vibrates violently in the vertical direction and falls down. Or has a problem that the stable behavior cannot be secured. Here, the high vibration is vibration including both high-load vibration and high-frequency vibration.

  An object of this invention is to provide the tensioner which can perform the stable behavior also with respect to such a high vibration and a transverse vibration.

  To achieve the above object, a tensioner according to a first aspect of the present invention includes a first shaft member and a second shaft member that are screwed together by a threaded portion, and a torsion spring that urges the first shaft member to rotate in one direction. Is a tensioner that is housed in a case and restrains the rotation of the second shaft member and converts the rotational biasing force of the torsion spring into the propulsive force of the second shaft member, and the shaft end of the first shaft member An elastic member for urging the first shaft member in the axial direction is provided so that the portion is in close contact with the case.

  According to the first aspect of the present invention, the elastic member acts to press the shaft end of the first shaft against the case, and the first shaft member can be operated even when high vibration including high load vibration and high frequency vibration is input. While restraining from floating from the case, a constant friction torque is always generated between the first shaft member and the case. For this reason, the entire behavior including the first shaft member and the second shaft member into which the first shaft member is screwed is stabilized.

  In the tensioner of the invention of claim 2, the first shaft member and the second shaft member screwed together by the threaded portion, and the torsion spring that urges the first shaft member to rotate in one direction are accommodated in the case. A tensioner that constrains the rotation of the second shaft member and converts the rotational biasing force of the torsion spring into the propulsive force of the second shaft member, and supports the first shaft member at at least two locations in the axial direction. The support member is disposed in the case.

  In the invention of claim 2, since the support member supports the first shaft member at at least two places, the first shaft member is firmly supported. For this reason, even if lateral vibration is input, the first shaft member does not fall down, and the entire behavior including the first shaft member and the second shaft in which the first shaft member is screwed is obtained. Stabilize.

  In the tensioner of the invention according to claim 3, the first shaft member and the second shaft member screwed together by the threaded portion, and the torsion spring for rotating and biasing the first shaft member in one direction are accommodated in the case. A tensioner that constrains the rotation of the second shaft member and converts the rotational urging force of the torsion spring into the propulsive force of the second shaft member so that the shaft end of the first shaft member is in close contact with the case. An elastic member for urging the first shaft member in the axial direction is provided, and a support member for supporting the first shaft member at at least two locations in the axial direction is disposed in the case. To do.

  In the invention of claim 3, since the elastic member acts so as to press the shaft end portion of the first shaft against the case, the first shaft member is prevented from being lifted from the case, and the support member is the first member. Since the shaft member is supported at at least two locations, the first shaft member is firmly supported. For this reason, even if high vibration consisting of high load vibration and high frequency vibration is input, the first shaft member does not float, and even if lateral vibration is input, the first shaft member does not fall down. Thereby, even when the engine rotates at a high speed, a stable behavior can be performed.

  A fourth aspect of the invention is the tensioner according to the second or third aspect, wherein each of the support members supports the outer peripheral surface of the first shaft member.

  In the invention of claim 4, since the support member supports the outer peripheral surface of the first shaft member, even if groove processing or other processing is performed on the shaft end portion of the first shaft member, The first shaft member can be supported independently. For this reason, the first shaft member can be supported stably.

  The invention of claim 5 is the tensioner according to any one of claims 1 to 4, wherein the first shaft member includes a shaft portion supported by the support member and the second shaft member. It is divided into screw shaft portions to be screwed together, and these are connected in a mutually engaged state.

  In the invention of claim 5, the divided shaft portion and the threaded shaft portion are engaged with each other, so that they rotate integrally. For this reason, it can operate similarly to a single shaft member.

  In addition, in the invention of claim 5, when the lateral vibration from the engine side is input to the second shaft member, the lateral vibration is transmitted to the screw shaft portion screwed to the second shaft member, and the screw The shaft performs a swinging motion following the lateral vibration. This swinging motion can attenuate or alleviate the lateral input load. Even at this time, at least two portions of the shaft portion with which the screw shaft portion is engaged are firmly supported by the support member, so that the shaft portion does not fall down. For this reason, the behavior as a whole is stabilized.

  According to the tensioner of the present invention, since the first shaft member does not float or fall down, stable behavior can be performed even when the engine rotates at a high speed.

  Hereinafter, the present invention will be specifically described with reference to embodiments illustrated in the drawings. In each embodiment, the same members are assigned the same reference numerals.

(Embodiment 1)
FIG. 1 shows a tensioner A1 according to Embodiment 1 of the present invention, which includes a case 2, a first shaft member 3, a second shaft member 4, a torsion spring 5, a guide 6, and a spacer 7.

  The case 2 has a trunk portion 2a and a flange portion 2b extending from the trunk portion 2a in a substantially orthogonal direction. A storage hole 2c extending in the axial direction (propulsion direction) is formed from the body portion 2a to the flange portion 2b. The front end portion of the storage hole 2c is open, and the assembly of the first and second shaft members 3 and 4, the torsion spring 5 and the spacer 7 is stored in the storage hole 2c.

  The flange portion 2b is to be attached to the engine main body, which is a device used, and is formed with an attachment hole 2d through which a bolt (not shown) screwed into the engine main body passes. At the time of attachment to the engine body, the front end surface of the flange portion 2b comes into contact with the attachment surface 250 of the engine body 200, as in FIG.

  The first shaft member 3 is rotated by being biased by the torsion spring 5, and the second shaft member 4 is propelled from the case 2 by the rotation of the first shaft member 3.

  The first shaft member 3 is integrally formed so that the proximal end side shaft portion 3a and the distal end side screw shaft portion 3b extend in the axial direction, and is formed on the outer periphery of the distal end side screw shaft portion 3b. The male screw 8 is formed. Further, the rotation of the base end portion (left end portion) of the shaft portion 3 a is supported by abutting against a receiving seat 15 provided in the case 2. The receiving seat 15 functions as a support member that supports the first shaft member 3. In the receiving seat 15, the shaft end 3f of the first shaft member 3 abuts from the axial direction, and the first shaft member 3 is supported by the abutment of the shaft end 3f.

  A slit 3e into which the tip of a winding jig (not shown) for rotating the first shaft 3 is inserted is formed in the shaft end 3f of the shaft 3a. The slit 3e communicates with a jig hole 2e formed in the base end surface of the body 2a of the case 2, and the distal end of the winding jig is inserted into the slit 3e from the jig hole 2e, and the first through the slit 3e. By rotating the shaft member 3, the torsion spring 5 can be wound. In the state of FIG. 1, a stopper 16 for preventing the rotation of the first shaft member 3 is inserted into the jig hole 2e and the slit 3e. A female screw is formed on the inner surface of the jig hole 2e so that a seal bolt 18 described later can be screwed together.

  The second shaft member 4 is formed in a cylindrical shape, and a female screw 9 into which the male screw 8 of the first shaft member 3 is screwed is formed on the inner surface thereof. The shaft members 3 and 4 are inserted into the housing hole 2c of the case 2 in a state where the female screw 9 and the male screw 8 are screwed together. A cap 10 is attached to the tip of the second shaft member 4 and is prevented from coming off by press-fitting a spring pin 11.

  In this embodiment, the torsion spring 5 is disposed on the second shaft member 4 side and is externally inserted into the screw shaft portion 3 b of the first shaft member 3. The torsion spring 5 has a hook portion 5a on one end side inserted into a hook groove (not shown) formed in the case 2 and locked, while a hook portion (not shown) on the other end side is a first shaft member. 3 is inserted and locked. For this reason, the first shaft member 3 can be rotated by winding the torsion spring 5 and applying torque.

  The guide 6 is attached to the tip portion of the case 2 and is fixed by a circlip 13. The guide 6 has a sliding hole 6a, and the second shaft member 4 passes through the sliding hole 6a so as to be slidable in the axial direction. The inner surface of the sliding hole 6a and the outer surface of the second shaft member 4 are formed in a substantially oval shape, D-cut or parallel cut, or other non-circular shape, whereby the rotation of the second shaft member 4 is restricted. It becomes a state. Further, a plurality of fixed pieces 6 b are formed radially on the outer peripheral side of the guide 6, and the fixed pieces 6 b are fitted into a notch groove formed in the distal end portion of the case 2, whereby the entire guide 6 is formed. Is stopped. The guide 6 is thus prevented from rotating with respect to the case 2, whereby the second shaft member 4 penetrating the guide 6 is rotationally restrained by the case 2 via the guide 6.

  The screw shaft portion 3b of the first shaft member 3 is screwed into the second shaft member 4 via the screw portions 8 and 9, and the first shaft member is rotated by the rotational biasing force of the torsion spring 5. 3 is transmitted to the second shaft member 4, but the second shaft member 4 advances and retreats with respect to the case 2 because the second shaft member 4 is rotationally restrained by the guide 6.

  The spacer 7 has a cylindrical shape, and a screwed portion of the screw shaft portion 3b and the second shaft member 4 is inserted therein. In this case, a flange portion 3c having a large diameter is formed at the boundary portion between the shaft portion 3a and the screw shaft portion 3b in the first shaft member 3, and the base end portion of the spacer 7 is formed on the flange portion 3c. It is in contact. The tip of the spacer 7 faces the guide 6, and the first and second shaft members 3, 4 are prevented from coming out of the case 2 by contact with the guide 6.

  Reference numeral 18 denotes a seal bolt. After the stopper 16 is pulled out from the case 2 with the tensioner A1 attached to the engine, oil leakage from the jig hole 2e is prevented by screwing it into the jig hole 2e of the case 2. Acts like

  In this embodiment, a coil spring 20 as an elastic member is disposed inside the case 2. The coil spring 20 is extrapolated to the shaft portion 3a of the first shaft member 3, and a compression spring is used.

  The coil spring 20 is externally inserted into the shaft portion 3a in a compressed state. A presser ring 21 is integrally formed on the proximal end side of the shaft portion 3a, and the housing hole 2c of the case 2 is formed. A presser ring 22 is press-fitted into the press. The coil spring 20 has free ends at both ends, and is arranged between the presser ring 21 and the presser ring 22 in a compressed state, so that the shaft end 3f of the first shaft member 3 is always on the receiving seat 15. It is energized to adhere closely. That is, the coil spring 20 acts so as to press the shaft end portion 3f of the first shaft member 3 against the receiving seat 15, whereby the coil spring 20 is received by the shaft end portion 3f of the first shaft member 3. It is urged so as to always come into close contact with the case 2 via the seat 15. The shaft portion 3a of the first shaft member 3 penetrates the presser ring 22 in a loosely inserted state.

  Due to the biasing of the coil spring 20 as an elastic member, the shaft end portion 3f of the first shaft member 3 is pressed against the case 2, so that a high vibration including a high load vibration and a high frequency vibration is input from the engine. However, it is possible to suppress the first shaft member 3 from floating from the case 2. A constant torque is always generated between the first shaft member 3 and the case 2 (receiving seat 15). This makes it possible to perform stable behavior even when high vibration is input.

(Embodiment 2)
FIG. 2 shows a tensioner A2 according to Embodiment 2 of the present invention. In this embodiment, in addition to the receiving seat 15 as a support member, a ring guide 25 that is another support member is provided.

  The ring guide 25 is fixed in the case 2 by forming a press-fit step portion 2g on the inner surface of the case 2 facing the shaft portion 3a of the first shaft member 3 and press-fitting the press-fit step portion 2g. Such a ring guide 25 supports the outer peripheral surface of the shaft portion 3a in a rotatable manner.

  The shaft portion 3a of the first shaft member 3 is formed with an engagement slit 3h extending along the axial direction, and the hook portion 5b on the other side of the torsion spring 5 is inserted into the hook groove 3f. It is locked.

  In such a structure, since the shaft portion 3a is supported by the receiving seat 15 on the shaft end portion 3f side and the intermediate portion is supported by the ring guide 25, the first shaft member 3 is attached to the case 2 at two locations. It is supported and can provide strong support. For this reason, even if lateral vibration is input via the second shaft member 4, the first shaft member 3 does not fall down. Thereby, the 1st shaft member 3 and the 2nd shaft member 4 can perform the stable operation | movement, and a behavior is stabilized. In this embodiment, the coil spring 20 as the elastic member in the first embodiment is not provided. However, since the first shaft member 3 is supported at two locations to prevent its collapse, stable behavior is achieved. It is something that can be done.

(Embodiment 3)
3 to 5 show a tensioner A3 according to Embodiment 3 of the present invention.

  In this embodiment, the first shaft member 3 is divided into two parts, that is, a shaft part 31 and a screw shaft part 32. The shaft portion 31 is located on the proximal end side, the screw shaft portion 32 is located on the distal end side (second shaft member 4 side), and the male screw portion 8 for the second shaft member 4 to be screwed together. Is formed on the outer peripheral surface.

  The shaft portion 31 and the screw shaft portion 32 have a structure in which opposing end surfaces engage with each other. That is, as shown in FIG. 6, a flange portion 3c with which the spacer 7 abuts is formed on the end surface on the proximal end side of the screw shaft portion 32, and the fitting protrusion having a circular cross section from the flange portion 3c. 32a protrudes, and further, an engaging protrusion 32b having a rectangular cross section protrudes from the fitting protrusion 32a. On the other hand, the end face on the front end side of the shaft portion 31 is engaged with the fitting groove 31a having the same shape as the fitting protrusion 32a into which the fitting protrusion 32a is inserted and the engaging protrusion 32b being inserted. An engagement slit 3h is formed.

  As shown in FIG. 3, the hook portion 5b on the other side of the torsion spring 5 is inserted into the engagement slit 3h of the shaft portion 31 and locked. For this reason, the rotational biasing force of the torsion spring 5 acts on the shaft portion 31.

  In a state where the shaft portion 31 and the screw shaft portion 32 are coupled in the axial direction, the engagement protrusion 32b is inserted into the engagement slit 3h and engaged, whereby the shaft portion 31 and the screw shaft portion 32 are integrated. Can be rotated. Thereby, it operate | moves similarly to the 1st shaft member which consists of a single rod.

  A presser ring 21 is integrally formed on the proximal end side of the shaft portion 31, and a small-diameter rod portion 33 protrudes from the presser ring 21. The slit 3 e into which the stopper 16 is inserted is formed on the end surface of the rod portion 33.

  In this embodiment, the first shaft member 3 is supported by a ring plate 27 and a ring guide 25 as support members. The ring guide 25 supports the intermediate portion of the shaft portion 31 in the first shaft member 3 by being press-fitted into the press-fitting step portion 2g formed in the case as in the second embodiment. FIG. 5 shows the ring guide 25, the outer peripheral surface of which is press-fitted into the press-fitting step portion 2g, and the shaft portion 31 is inserted into and supported by the central through hole. Thereby, the ring guide 25 supports the outer peripheral surface of the shaft portion 31.

  The ring plate 27 is fixed by being press-fitted into the base end side of the housing hole 2 c of the case 2. FIG. 4 shows the ring plate 27, and a through hole 27 a into which the rod portion 33 is inserted is formed in the central portion. The ring plate 27 supports the shaft portion 31 by the inner surface of the through hole 27a. The ring plate 27 supports the outer peripheral surface of the shaft portion 31 together with the ring guide 25. In such a support by the ring plate 27, the slit 3e does not come into contact with the case 2, and the rotational torque of the shaft portion 31 does not fluctuate due to the slit 3e, so that the first shaft member 3 can rotate stably. it can.

  In such an embodiment, as in the second embodiment, the first shaft member 3 is supported by the case 2 at two locations of the ring guide 25 and the ring plate 27, so that strong support can be performed. . In particular, in this embodiment, the first shaft member 3 is divided into a shaft portion 31 and a screw shaft portion 32 on the second shaft member 4 side, and the lateral vibration from the engine side is the second shaft. When input to the member 4, lateral vibration is transmitted to the screw shaft portion 32 that is screwed into the second shaft member 4. Thereby, since the screw shaft portion 32 performs a swing motion following the lateral vibration, the lateral input load can be attenuated or reduced by the swing motion. Even at this time, the shaft portion 32 with which the screw shaft portion 32 is engaged is supported at two locations by the ring guide 25 and the ring plate 27, so that the shaft portion 32 is stably supported by the case 2 without falling down. It is in a state. Thereby, the behavior as a whole is stabilized. In addition to this, since the first shaft member 3 is constituted by two members of the shaft portion 31 and the screw shaft portion 32, there is an advantage that the degree of freedom in assembling the tensioner is increased.

  In this embodiment, the sliding hole 6 a of the guide 6 through which the second shaft member 4 passes in a rotationally restricted state is opened so as to be larger than the outer shape of the second shaft member 4. The sliding hole 6a is for restricting the rotation of the second shaft member 4, and is therefore formed in a non-circular shape similar to the second shaft member 4, but its diameter is the second shaft member 4. It opens so that it may become larger. Thus, by opening the sliding hole 6a greatly, a gap can be secured between the sliding hole 6a and the second shaft member 4, and the second movement accompanying the swinging motion of the screw shaft portion 32 can be secured. The swing motion of the shaft member 4 can be ensured. Accordingly, the screw shaft portion 32 and the second shaft member 4 are not screwed together, so that the screw shaft portion 32 (that is, the first shaft member 3) is smoothly moved by the advancement and retreat of the second shaft member 4. It is possible to ensure a smooth operation.

(Embodiment 4)
FIG. 7 shows a tensioner A4 according to Embodiment 4 of the present invention.

  In the tensioner A4 in this embodiment, the first shaft member 3 is divided into two members of a shaft portion 31 and a screw shaft portion 32. The shape and connection structure of the shaft portion 31 and the screw shaft portion 32 are the same as those of the tensioner A3 in the third embodiment shown in FIG.

  In this embodiment, the shaft portion 31 of the first shaft member 3 is supported at two locations by a ring guide 25 and a ring plate 27 as support members. The support by the ring guide 25 and the ring plate 27 is the same as that of the third embodiment shown in FIGS.

  Further, in this embodiment, a coil spring 20 as an elastic member is provided. The coil spring 20 is disposed in a compressed state between the presser ring 21 of the shaft portion 31 in the first shaft member 3 and the ring guide 25 press-fitted into the case 2, thereby the first shaft member. 3 is biased so that the shaft end portion 3 f always abuts against the ring plate 27. Therefore, the shaft end portion 3f of the first shaft member 3 is urged in the axial direction via the ring plate 27 so as to be always in close contact with the case 2 as in the first embodiment. Therefore, even when high vibrations including high load vibrations and high frequency vibrations are input from the engine, the first shaft member 3 can be prevented from floating from the case 2, and stable behavior can be achieved even when high vibrations are input. It is possible to do.

  In this embodiment, similarly to the third embodiment, the first shaft member 3 is screwed into the shaft portion 31 supported by the ring guide 25 and the ring plate 27 and the second shaft member 4. Since the screw shaft 32 performs a swinging motion following the lateral vibration by the lateral vibration input to the second shaft member 4 from the engine side, the lateral movement is caused by the swinging motion. The shaft portion 32 with which the screw shaft portion 32 is engaged is supported at two locations by the ring guide 25 and the ring plate 27, so that it does not fall down. The case 2 is stably supported. Thereby, the behavior as a whole is stabilized. In order to secure such a swinging motion, the sliding hole 6a of the guide 6 through which the second shaft member 4 passes in a rotationally restricted state is opened so as to be larger than the outer shape of the second shaft member 4. is there.

  As described above, in this embodiment, even if high vibration is input, the first shaft member is not lifted, and even if lateral vibration is input, the swinging motion is performed to attenuate and mitigate the lateral vibration. Therefore, even when the engine rotates at a high speed, a stable behavior can be performed. In addition to this, the slit 3e of the shaft portion 31 does not come into contact with the case 2, and the rotational torque of the shaft portion 31 does not fluctuate due to the slit 3e. Therefore, the first shaft member 3 can rotate stably. .

(Embodiment 5)
FIG. 8 shows a tensioner A5 according to the fifth embodiment of the present invention.

  In the tensioner A5 of this embodiment, the first shaft member 3 is divided into two members, a shaft portion 31 and a screw shaft portion 32, as in the third and fourth embodiments. The coil spring 20 as an elastic member is disposed between the press ring 21 of the shaft portion 31 of the first shaft member 3 and the ring guide 25 press-fitted into the case 2 in a compressed state. The shaft end portion 3f of the first shaft member 3 is urged so as to be always in close contact with the ring plate 27 (that is, the case 2).

  In this embodiment, the intermediate portion of the shaft portion 31 of the first shaft member 3 is supported by the ring guide 25 as a support member, and the shaft end portion 3f of the shaft portion 31 is attached to the receiving seat 15 as the support member. It is supported by contact.

  In such an embodiment, the axial end portion 3f of the first shaft member 3 is pressed against the case 2 by the bias of the coil spring 20, so that even if high vibration is input from the engine, the first shaft member 3 is pressed. Is prevented from floating from the case 2. Further, even if lateral vibration is input from the engine side to the second shaft member 4, the screw shaft portion 32 that is screwed with the second shaft member 4 performs a swinging motion following the lateral vibration. The input load in the direction can be attenuated or alleviated, and the shaft portion 32 with which the screw shaft portion 32 is engaged is supported by the ring guide 25 and the ring plate 27 at two locations, so that it does not fall down. The overall behavior is stable. For this reason, even when the engine rotates at a high speed, a stable behavior can be performed. Also in this embodiment, the screw 6 is opened by opening the sliding hole 6a of the guide 6 through which the second shaft member 4 passes in a rotationally restricted state so as to be larger than the outer shape of the second shaft member 4. The swing motion of the shaft portion 32 and the second shaft member 4 is ensured.

(Embodiment 6)
In this embodiment, another structure when the first shaft member 3 is divided into a shaft portion 31 and a screw shaft portion 32 is shown.

  In FIG. 9, the fitting protrusion 32a in the screw shaft portion 32 is tapered and rises from the flange portion 3c. Correspondingly, the fitting groove 31a of the shaft portion 31 is formed in a tapered shape so that the fitting protrusion 32a is in close contact therewith. In such a structure, the shaft portion 31 and the screw shaft portion 32 can be firmly engaged with each other.

  10 and 11, the fitting protrusion 32a of the screw shaft portion 32 is formed of a hexahedron (see FIG. 11), and the fitting groove 31a of the shaft portion 31 has a groove shape corresponding to the fitting protrusion 32a. Is formed. In the fitted state with the fitting protrusion 32a and the fitting groove 31a, there is an advantage that the shaft portion 31 and the screw shaft portion 32 can be firmly coupled.

  In the above embodiment, the first shaft member 3 is supported at two locations. However, in the present invention, the first shaft member 3 may be supported at three or more locations.

It is sectional drawing of the tensioner in Embodiment 1 of this invention. It is sectional drawing of the tensioner in Embodiment 2 of this invention. It is sectional drawing of the tensioner in Embodiment 3 of this invention. It is sectional drawing of the ring plate which is a support member. It is sectional drawing of the ring guide which is a support member. It is a side view which shows the state which divided | segmented the 1st shaft member. It is sectional drawing of the tensioner in Embodiment 4 of this invention. It is sectional drawing of the tensioner in Embodiment 5 of this invention. It is sectional drawing which shows another structure which divided | segmented the 1st shaft member. (A), (b) is the side view and front view of the shaft part in another structure which divided | segmented the 1st shaft member. (A), (b) is the side view and front view of the screw shaft part in another structure which divided | segmented the 1st shaft member. It is sectional drawing of the state which mounted | wore the engine main body with the tensioner. It is sectional drawing which shows a general tensioner.

Explanation of symbols

2 Case 3 First shaft member 4 Second shaft member 5 Torsion spring 8 Male screw portion 9 Female screw portion 15 Receiving seat (support member)
20 Coil spring (elastic member)
25 Ring guide (support member)
27 Ring plate (support member)

Claims (5)

A first shaft member and a second shaft member that are screwed together by the threaded portion, and a torsion spring that urges the first shaft member to rotate in one direction are accommodated in the case, and restrains the rotation of the second shaft member. A tensioner that converts the rotational biasing force of the torsion spring into the propulsive force of the second shaft member,
A tensioner provided with an elastic member for urging the first shaft member in the axial direction so that the shaft end portion of the first shaft member is in close contact with the case. A first shaft member and a second shaft member that are screwed together by the threaded portion, and a torsion spring that urges the first shaft member to rotate in one direction are accommodated in the case, and restrains the rotation of the second shaft member. A tensioner that converts the rotational biasing force of the torsion spring into the propulsive force of the second shaft member,
A tensioner, wherein a support member for supporting the first shaft member in at least two locations in the axial direction is disposed in the case. A first shaft member and a second shaft member that are screwed together by the threaded portion, and a torsion spring that urges the first shaft member to rotate in one direction are accommodated in the case, and restrains the rotation of the second shaft member. A tensioner that converts the rotational biasing force of the torsion spring into the propulsive force of the second shaft member,
An elastic member for urging the first shaft member in the axial direction is provided so that the shaft end portion of the first shaft member is in close contact with the case, and the first shaft member is disposed at at least two locations in the axial direction. A tensioner, wherein a supporting member to be supported is disposed in a case.   4. The tensioner according to claim 2, wherein each of the support members supports the outer peripheral surface of the first shaft member. 5.   5. The tensioner according to claim 1, wherein the first shaft member includes a shaft portion supported by the support member and a screw shaft portion into which the second shaft member is screwed. A tensioner which is divided and connected in an engaged state with each other.

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