JPWO2012099026A1 - Tensioner - Google Patents

Abstract

Provided is a tensioner that can prevent movement of the other end of the spring with a simple structure, is easy to process, and can be assembled by a simple operation that does not require skill. The first shaft member 2 and the second shaft member 3 screwed together by the threaded portion, the spring 4 that urges the first shaft member 2 to rotate, and the first shaft member 2 and the second shaft member 3 coming out from the case 1. And a spacer 5 for preventing the above. One end 41 of the spring 4 is locked to the first shaft member 2, and the other end 42 is locked to a slit 6 formed in the length direction of the case 1. A movement restricting member 9 that restricts the movement of the other end 42 of the spring 4 in the length direction of the slit 6 is inserted into the slit 6.

Description

  The present invention relates to a tensioner that keeps the tension of an endless belt or tune constant.

  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 contracted.

  FIG. 14 shows a state in which the tensioner 100 is mounted on the engine body 200 of the automobile. A pair of cam sprockets 210, 210 and a crank sprocket 220 are arranged inside the engine body 200, and the timing chain 230 is stretched between these sprockets 210, 210, 220 in an endless manner. Yes. On the moving path of the timing chain 230, a tune guide 240 is slidably disposed. The tensioner 100 is fixed to the mounting surface 250 by bolts 260 while penetrating the mounting surface 250 of the engine body 200. In this attached state, the tip of the tensioner 100 abuts on the chain guide 240 and pushes the timing chain 230 via the chain guide 240 to keep the tension of the timing chain 230 constant.

  FIG. 15 shows a tensioner 100 conventionally used. As shown in FIGS. 15B and 15C, the first shaft member 120 and the second shaft member 130 that are screwed together and the spring 140 that rotationally biases the first shaft member 120 are the main body portion 111 of the case 110. Is housed inside. The case 110 is formed by aluminum die casting, pressing, or the like. The case 100 is fixed to the engine main body 200, and a flange portion 112 that abuts on the mounting surface 250 of the engine main body 200 and is bolted is integrally formed at the rear end portion in the length direction of the main body portion 111. Yes.

  When the first shaft member 120 and the second shaft member 130 are screwed together, the external thread portion 121 is formed on the outer surface of the first shaft member 120, while the internal thread portion 131 is formed on the inner surface on the rear end side of the second shaft member 130. And these are made by screwing together. The first shaft member 120 is rotatably supported by the case 110. For rotation support of the first shaft member 120, a support recess 113 is formed in the flange portion 112 of the case 110, and the rear end portion of the first shaft member 120 is inserted into and supported by the shaft receiver 150 press-fitted into the support recess 113. It is made by.

  The spring 140 is provided corresponding to the rear end portion of the first shaft member 120, and a spring that is extrapolated around the first shaft member 120 is used. One end 141 of the spring 140 is locked to a locking slit 122 formed at the rear end of the first shaft member 120, and the other end 142 is locked to the main body 111 of the case 110. Accordingly, the spring 140 urges the first shaft member 120 to rotate. A washer 180 is provided for the spring 140. The washer 180 is externally attached to the first shaft member 120 and covers the upper portion of the spring 140, thereby preventing the spring 140 from moving in the length direction of the first shaft member 120.

  In order to lock the other end 142 of the spring 140 to the main body 111 of the case 110, a slit 114 is formed in the main body 111 of the case 110. The other end 142 of the spring 140 is locked by being inserted into the slit 114. The slit 114 is formed over the entire length of the main body 111 of the case 110 as in the case of Patent Document 4. Thus, in the structure in which the slit 114 is formed over the entire length of the main body 111, the other end 142 of the spring 140 can be easily inserted into the slit 114, and the other end 142 of the spring 140 can be easily locked. It becomes possible. The spring 140 may be a torsion spring as well as a spring, and also in the case of a torsion spring, one end is locked to the first shaft member 120 and the other end is locked to the slit of the case. Thus, the first shaft portion 120 can be urged to rotate.

  The second shaft member 130 passes through the bearing 160 and has a leading end extracted outside the case 110. The bearing 160 is fixed to the tip of the main body 111 of the case 110 in a state of being prevented from coming off by a retaining ring 170. The outer surface of the second shaft member 130 penetrating the bearing 160 and the inner surface of the bearing 160 on which the outer surface slides are non-circular such as a parallel cut and a D cut, and the rotation of the second shaft member 130 is thereby restricted. Therefore, the second shaft member 130 moves forward and backward with respect to the case 110.

  A cylindrical spacer 190 is disposed on the outer periphery of the first shaft member 120 and the second shaft member 130. The spacer 190 is disposed between the bearing 160 and the washer 180, and prevents the shaft members 120 and 130 in a screwed state from coming out of the main body 111 of the case 110.

  In the tensioner 100 described above, the other end 142 of the spring 140 receives torque in the rotational direction, and when an excessive movement is applied, the other end 142 can move in the slit 114 so as to be displaced in the vertical direction. is there. When the other end 142 moves in the vertical direction in this manner, the other end 142 is sandwiched between the case 110 and the washer 180, so that the urging force of the spring 140 fluctuates and the second shaft member 130 is favorably urged. The problem that can not be done occurs. For this reason, it is necessary to prevent the other end 142 of the spring 140 from moving.

  In Patent Documents 1 and 2, a window hole made of a square hole or a round hole is formed in the main body 111 of the case 110, and the other end 142 of the spring 140 is locked in this window hole. Even if the other end 142 of the spring 140 moves in the window hole, the amount of movement is limited, so that the other end 142 is not greatly displaced and there is no adverse effect.

  Further, in Patent Document 3, a rising wall is provided on the shaft receiver 150 that supports the first shaft member 120, a locking claw is formed on the wall, and the other end of the spring 140 is formed on the locking claw. The part 142 is locked. In Patent Document 3, since the shaft receiver 150 is not press-fitted into the flange portion 112 of the case 110 and moved, the movement of the other end 142 of the spring 140 can be prevented.

  FIG. 16 shows another structure for preventing the other end 142 of the spring 140 from moving. A concave groove 115 that is recessed stepwise is formed at the base portion of the main body 111 of the case 110, and the other end 142 of the spring 140 is inserted into the concave groove 115 to restrict the movement of the other end 142. Is.

Japanese Patent No. 4228359 Japanese Patent No. 3526679 Japanese Patent No. 4243679 JP 2008-223790 A

  However, in the structures described in Patent Documents 1 and 2, the operation of inserting and locking the other end 142 of the spring 140 into the window hole of the case is troublesome and requires skill. In addition, since a window hole is provided in the case, it is necessary to make a hole when processing the case with a press, and a hole with a slide is required when processing with a die casting, which makes the process complicated and expensive. The same applies to the structure described in Patent Document 3, and the operation of locking the other end 142 of the spring 140 to the locking claw is troublesome and requires skill. Moreover, the structure of the shaft receiver is complicated, and the processing of the shaft receiver is cumbersome and expensive.

  In the structure shown in FIG. 16, when the case 110 is formed by aluminum die casting, the concave groove 115 is undercut on the surface indicated by the reference numeral 300, so that it cannot be released. In order to form the concave groove 115, it is necessary to perform a cutting process or to set the dividing surface to a surface indicated by reference numeral 400. However, since cutting is necessary in the cutting process, the processing becomes troublesome and the surface 400 is divided. However, there is a problem that mold division becomes complicated and mold life is shortened.

  The present invention has been made in view of such conventional problems, and the movement of the other end of the spring can be prevented with a simple structure, and the processing is easy and requires skill. The purpose is to provide a tensioner that can be assembled with no simple work.

  In the tensioner according to the present invention, a first shaft member and a second shaft member screwed together by a screw portion, and a spring for rotating and biasing the first shaft member are accommodated in a case, and the first shaft in the screwed state is accommodated. Spacers are provided around the outside of the first shaft member and the second shaft member to prevent the member and the second shaft member from coming out of the case, and the rotation of the second shaft member is constrained to rotate the spring. A tensioner that converts a force to a propulsive force of a second shaft member, wherein one end of the spring is engaged with the first shaft member and the other end is engaged with a slit formed in the length direction of the case. A movement restricting member that is stopped and restricts movement of the other end of the spring in the length direction of the slit is inserted into the slit.

  In this case, the movement restricting member is formed by a main body portion that is inserted into the slit, and an engaging convex portion that is integrally formed with the main body portion and engages with the inner edge portion and the outer edge portion of the slit. Preferably it is.

  Further, it is preferable that the movement restricting member comprises a protrusion formed so as to integrally extend outward from the spacer, and the protrusion is inserted into the slit.

  Further, a bottom plate portion extending inwardly is formed at a rear end portion in the length direction of the spacer, and the bottom plate portion enters an axial gap between the first shaft member and the second shaft member. preferable.

  Further, it is preferable that the dimension of the gap when the second shaft member is retracted to the maximum is larger than the thickness of the bottom plate portion.

  Further, a cap that contacts the first shaft member when the second shaft member is retracted to the maximum is attached to a distal end portion of the second shaft member in the length direction, and the cap contacts the first shaft member It is preferable that the dimension of the gap at the time is larger than the thickness of the bottom plate portion.

  According to the present invention, since the other end of the spring is locked to the slit formed in the length direction of the case and the movement restricting member for restricting the movement of the other end of the spring is inserted into the slit, It is possible to prevent the other end of the spring from moving in the slit. Therefore, the movement of the other end of the spring can be prevented with a simple structure. Further, since only the movement restricting member is inserted into the slit, the processing is easy, and a simple operation without requiring skill can be achieved.

It is a front view showing tensioner A1 of a 1st embodiment of the present invention. (A) is the cross section from the plane of tensioner A1, (b) F2-F2 sectional view taken on the line, (b) is F1-F1 sectional view taken on the line of FIG. The movement control member in tensioner A1 is shown, (a) is a top view, (b) is a front view, (c) is a side view. It is a front view which shows tensioner A2 of 2nd Embodiment of this invention. (A) is the cross section from the plane of tensioner A2, G2-G2 sectional view taken on the line of (b), (b) is G1-G1 sectional view taken on the line of FIG. The first form of the spacer in the tensioner A2 is shown, (a) is a plan view, (b) is a front view, (c) is a sectional view taken along line H1-H1 of (a), and (d) is a bottom view. The 2nd form of the spacer of 2nd Embodiment is shown, (a) is a top view, (b) is a front view, (c) is the J1-J1 sectional view taken on the line of (a), (d) is a bottom view. . The 3rd form of the spacer of 2nd Embodiment is shown, (a) is a top view, (b) is a front view, (c) is K1-K1 sectional view taken on the line of (a), (d) is a bottom view. . The 4th form of the spacer of 2nd Embodiment is shown, (a) is a top view, (b) is a front view, (c) is L1-L1 sectional view taken on the line of (a), (d) is a bottom view. . It is a front view which shows tensioner A3 of 3rd Embodiment of this invention. (A) is the cross section from the plane of tensioner A3, (b) M2-M2 sectional view taken on the line, (b) is M1-M1 sectional view taken on the line of FIG. The spacer in tensioner A3 is shown, (a) is a top view, (b) is a front view, (c) is a sectional view taken along line M3-M3 of (b), and (d) is a bottom view. It is a longitudinal cross-sectional view which shows tensioner A4 of 4th Embodiment of this invention. It is a front view of the engine main body which mounted the tensioner. (A) is a front view of a conventional tensioner, (b) is a sectional view taken along line E2-E2 of (a), and (c) is a sectional view taken along line E1-E1 of (b). It is a front view which shows the case of the improved conventional tensioner.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in each embodiment, the same code | symbol is attached | subjected to the same member and it is made to respond | correspond.

(First embodiment)
1 to 3 show a tensioner A1 according to the first embodiment of the present invention. As shown in FIG. 2, the case 1, the first shaft member 2 and the second shaft member 3 in a screwed state, a spring 4, and And a spacer 5.

  The case 1 is formed by aluminum die casting, and includes a cylindrical main body portion 11 and a flange portion 12 formed integrally with a rear end portion in the length direction of the main body portion 11. The flange portion 12 is fixed to the engine main body 200 (see FIG. 14), and a bolt hole 12a for fixing to the engine main body 200 is formed. A support recess 13 for supporting the rotation of the first shaft member 2 is formed in the approximate center of the upper surface of the flange portion 12.

  The main body 11 accommodates the first shaft member 2 and the second shaft member 3 and the spring 4 that are screwed together, and is formed in a tapered tube shape and is erected from the upper surface of the flange portion 12. A slit 6 is formed in the main body 11. A pair of slits 6 is formed so as to face each other, and each slit 6 is provided over the entire length of the main body 11 in the length direction. The slit 6 is formed in consideration of the draft at the time of die casting, so that the slit 6 gradually becomes wider toward the distal end side (the distal end side in the length direction of the shaft members 2 and 3).

  The first shaft member 2 and the second shaft member 3 are screwed together by forming a male screw portion 21 on the outer periphery of the first shaft member 2 and a female screw portion 31 on the inner periphery of the second shaft member 3. It is made by screwing the part 21 and the female thread part 31 together. The first shaft member 2 is rotatably supported by the case 1, and the rear end portion 22 having a large diameter is supported by the flange portion 12 of the case 1. In this case, the shaft receiver 14 is fixed to the support recess 13 of the flange portion 12 by press-fitting, and the first shaft member 2 is inserted into and supported by the rear end portion 22 of the first shaft member 2 to be supported. 2 is rotatably supported by the flange portion 12 (case 1). A locking slit portion 23 is formed in the rear end portion 22 of the first shaft member 2 along the length direction.

  In the first shaft member 2, the female screw portion 31 is formed at the rear end portion in the length direction, and the female screw portion 31 is screwed into the male screw portion 21 of the first shaft member 2. In this screwed state, the distal end portion 32 of the second shaft member 3 is extracted from the distal end portion of the case 1 (main body portion 11). The cap 10 is fixed to the distal end portion 32 by caulking.

  A bearing 7 is fixed to a distal end portion of the main body 11 of the case 1 by a retaining ring 7a so as to be prevented from coming off, and the second shaft member 3 is slidably passed through the bearing 7 so that its rotation is restricted. ing. In order to restrict the rotation of the second shaft member 3, the outer surface of the second shaft member 3 and the inner surface of the bearing 7 on which the outer surface slides are formed in a non-circular shape such as a parallel cut, a D cut, an ellipse, or a polygon. ing. In such a structure, the second shaft member 3 linearly moves forward and backward by the rotational force of the first shaft member 2 rotating, and the tension of the timing chain in the engine body 200 is increased by the forward and backward movement of the second shaft member 3. It is designed to keep it constant.

  The spring 4 rotates and urges the first shaft member 2. In this embodiment, a spring that is extrapolated to the rear end portion 22 of the first shaft member 2 is used. The spring 4 is inserted into the engagement slit portion 23 of the rear end portion 22 of the first shaft member 2 with the end portion 41 on the inner side being inserted into the rear end portion 22 of the first shaft member 2 and locked. ing. The other end 42 on the outer side of the spring 4 is locked through one slit 6 of the main body 11 (case 1). As shown in FIG. 1, the other end 42 of the spring 4 is engaged with the slit 6 by being wound around the main body 11 while being positioned on the rear end side of the slit 6.

  A washer 8 is provided on the top of the spring 4. The washer 8 corresponds to a small-diameter continuous portion 24 that is continuous with the rear end portion 22 of the first shaft member 2, and is disposed so that the continuous portion 24 is loosely inserted. Thereby, the washer 8 can come into contact with the rear end portion 22 of the first shaft member 2. Thus, by providing the washer 8 in the continuous part 24, the washer 8 has covered the upper part of the spring 4, and has prevented the spring 4 from moving to the length direction of the 1st shaft member 2. FIG. .

  The spacer 5 is formed in a cylindrical shape, and is disposed around the outer sides of the first shaft member 2 and the second shaft member 3 that are screwed together. Both ends of the spacer 5 in the length direction are sandwiched between a washer 8 and a bearing 7, and the spacer 5 prevents the spacer 5 from being removed from the case 1. Further, the rear end side can come into contact with the second shaft member 3, and this contact prevents the washer 8 from moving in the length direction of the first shaft member 2 (the direction from the case 1). doing. As described above, the rear end portion 22 of the first shaft member 2 can come into contact with the washer 8, and the first shaft member 2 moves in the length direction (the direction of removal from the case 1) of the washer 8. To prevent that. Thus, the spacer 5 prevents the first shaft member 2 and the second shaft member 3 in the screwed state from coming out of the case 1.

  In this embodiment, a movement restricting member 9 is provided in addition to the above constituent members. The movement restricting member 9 is inserted into one slit 6 formed in the main body 11 of the case 1. As shown in FIG. 3, the movement restricting member 9 has a vertically long shape extending in the length direction of the slit 6, and a main body 91 inserted into the slit 6 and a pair of inner members integrally formed with the main body 91. It is formed by a mating convex portion 92 and a pair of outer engaging convex portions 93. The entire movement restricting member 9 is made of an appropriate material such as aluminum die casting, steel, resin such as rubber.

  As shown in FIG. 2, the pair of inner engagement protrusions 92 correspond to the inner edge 61 of the slit 6 and engage with the inner edge 61 of the slit 6. The pair of outer engagement protrusions 93 correspond to the outer edge 62 of the slit 6 and engage with the outer edge 62 of the slit 6. Due to these engagements, the movement restricting member 9 is inserted into the slit 6 while being prevented from coming off.

  The entire outer shape of the movement restricting member 9 is formed in accordance with the shape of the slit 6 to be inserted, and for this reason, the shape gradually becomes wider toward the distal end side (bearing 9 side). Further, the distal end portion 94 in the length direction of the movement restricting member 9 is in contact with the lower surface of the bearing 7 in a state of being inserted into the slit 6. By this contact, the movement restricting member 9 is in a fixed position with respect to the slit 6. The rear end portion 95 in the length direction of the movement restricting member 9 faces the upper portion of the other end portion 42 of the spring 4 locked to the slit 6 (see FIG. 2B). As a result, the movement restricting member 9 prevents the other end portion 42 of the spring 4 from shifting and moving toward the tip end side (upper side) of the case 1.

  According to such an embodiment, the other end 42 of the spring 4 is locked in the slit 6 formed in the length direction of the case 1 and the movement restricting member that restricts the movement of the other end 42 of the spring 4. Since 9 is inserted into the slit 6 at a fixed position, the other end 42 of the spring 4 can be prevented from moving in the slit 6. For this reason, the movement of the other end 42 of the spring 4 can be prevented with a simple structure. Further, since only the movement restricting member 9 is inserted into the slit 6, the processing is easy, and a simple operation without requiring skill can be achieved.

(Second Embodiment)
4 to 6 show a tensioner A2 according to a second embodiment of the present invention. As shown in FIG. 5, the tensioner A <b> 2 includes a first shaft member 2 and a second shaft member 3 that are screwed together, a spring 4, and a spacer 5.

  The case 1 is formed by aluminum die casting, and includes a cylindrical main body portion 11 and a flange portion 12 formed integrally with a rear end portion in the length direction of the main body portion 11. The flange portion 12 is fixed to the engine main body 200 (see FIG. 14), and a bolt hole 12a for fixing to the engine main body 200 is formed. A support recess 13 for supporting the rotation of the first shaft member 2 is formed in the approximate center of the upper surface of the flange portion 12.

  The main body 11 accommodates the first shaft member 2 and the second shaft member 3 and the spring 4 that are screwed together, and is formed in a tapered tube shape and is erected from the upper surface of the flange portion 12. A slit 6 is formed in the main body 11. A pair of slits 6 is formed so as to face each other, and each slit 6 is provided over the entire length of the main body 11 in the length direction. The slit 6 is formed in consideration of the draft at the time of die casting, so that the slit 6 gradually becomes wider toward the distal end side (the distal end side in the length direction of the shaft members 2 and 3).

  The first shaft member 2 and the second shaft member 3 are screwed together by forming a male screw portion 21 on the outer periphery of the first shaft member 2 and a female screw portion 31 on the inner periphery of the second shaft member 3. It is made by screwing the part 21 and the female thread part 31 together. The first shaft member 2 is rotatably supported by the case 1, and the rear end portion 22 having a large diameter is supported by the flange portion 12 of the case 1. In this case, the shaft receiver 14 is fixed to the support recess 13 of the flange portion 12 by press-fitting, and the first shaft member 2 is inserted into and supported by the rear end portion 22 of the first shaft member 2 to be supported. 2 is rotatably supported by the flange portion 12 (case 1). A locking slit portion 23 is formed in the rear end portion 22 of the first shaft member 2 along the length direction.

  In the first shaft member 2, the female screw portion 31 is formed at the rear end portion in the length direction, and the female screw portion 31 is screwed into the male screw portion 21 of the first shaft member 2. In this screwed state, the distal end portion 32 of the second shaft member 3 is extracted from the distal end portion of the case 1 (main body portion 11). The cap 10 is fixed to the distal end portion 32 by caulking.

  A bearing 7 is fixed to a distal end portion of the main body 11 of the case 1 by a retaining ring 7a so as to be prevented from coming off, and the second shaft member 3 is slidably passed through the bearing 7 so that its rotation is restricted. ing. In order to restrict the rotation of the second shaft member 3, the outer surface of the second shaft member 3 and the inner surface of the bearing 7 on which the outer surface slides are formed in a non-circular shape such as a parallel cut, a D cut, an ellipse, or a polygon. ing. In such a structure, the second shaft member 3 linearly moves forward and backward by the rotational force of the first shaft member 2 rotating, and the tension of the timing chain in the engine body 200 is increased by the forward and backward movement of the second shaft member 3. It is designed to keep it constant.

  The spring 4 rotates and urges the first shaft member 2. In this embodiment, a spring that is extrapolated to the rear end portion 22 of the first shaft member 2 is used. The spring 4 is inserted into the engagement slit portion 23 of the rear end portion 22 of the first shaft member 2 with the end portion 41 on the inner side being inserted into the rear end portion 22 of the first shaft member 2 and locked. ing. The other end 42 on the outer side of the spring 4 is locked through one slit 6 of the main body 11 (case 1). As shown in FIG. 1, the other end 42 of the spring 4 is engaged with the slit 6 by being wound around the main body 11 while being positioned on the rear end side of the slit 6.

  A washer 8 is provided on the top of the spring 4. The washer 8 corresponds to a small-diameter continuous portion 24 that is continuous with the rear end portion 22 of the first shaft member 2, and is disposed so that the continuous portion 24 is loosely inserted. Thereby, the washer 8 can come into contact with the rear end portion 22 of the first shaft member 2. Thus, by providing the washer 8 in the continuous part 24, the washer 8 has covered the upper part of the spring 4, and has prevented the spring 4 from moving to the length direction of the 1st shaft member 2. FIG. .

  The spacer 5 includes a cylindrical spacer body 51 that surrounds the first shaft member 2 and the second shaft member 3 that are screwed together, and a protrusion 52 that is integrally extended radially outward from the spacer body 51. Is formed. The spacer main body 51 is sandwiched between the washer 8 and the bearing 7 at both ends in the length direction, and the spacer 5 prevents the spacer 5 from coming off the case 1. Further, the rear end side can come into contact with the washer 8, and this contact prevents the washer 8 from moving in the length direction of the first shaft member 2 (the direction from which the case 1 is removed). . The rear end portion 22 of the first shaft member 2 can come into contact with the washer 8, and the first shaft member 2 is prevented from moving in the length direction (the direction in which the first shaft member 2 is detached from the case 1). The spacer 5 having such a spacer body 51 prevents the screwed first shaft member 2 and the second shaft member 3 from coming out of the case 1.

  The protrusion 52 has a length corresponding to substantially the entire length of the spacer body 51 and is integrally formed on the outer side of the spacer body 51. The protrusion 52 is solid and has a shape that matches the slit 6 formed in the case 1. For this reason, the protrusion 52 is gradually widened toward the distal end side (the distal end side in the length direction of the shaft members 2 and 3).

  The protrusion 52 is inserted into the slit 6 of the case 1 (main body 11) so that the front end 52 a faces the bearing 7 and the rear end 52 b faces the other end 42 of the spring 4. In this embodiment, the rear end portion 52 b is longer than the length of the spacer body 51 and extends in the direction of the other end portion 42 of the spring 4. By setting the extension amount of the rear end portion 52b to an amount corresponding to the plate thickness of the washer 8, the rear end portion 52b can be brought closer to the other end portion 42 of the spring 4, The shift movement of the end portion 42 can be restricted.

  In such an embodiment, when the spacer 5 is inserted into the case 1, the protrusion 52 is inserted into the slit 6 of the case 1. In this state, since the spacer 5 is sandwiched between the bearing 7 and the washer 8 and the movement of the spacer 5 is restricted, the protrusion 52 is in a fixed position in the slit 6. At this time, the other end portion 42 of the spring 4 enters the portion surrounded by the opposing surface of the slit 6 and the rear end portion 52 b of the projection 52, and the other end portion 42 of the spring 4 moves in the slit 6. Can be regulated. In such an embodiment, the protrusion 52 of the spacer 5 serves as a movement restricting member that restricts the movement of the other end 42 of the spring 4 and prevents the other end 42 of the spring 4 from moving with a simple structure. be able to. In this embodiment, the protrusion 52 as a movement restricting member is formed integrally with the spacer 5, and there is no need to provide a separate movement restricting member. For this reason, it becomes easy to process and can be assembled by a simple operation that does not require skill.

  FIG. 7 shows a second form of the spacer 5 used in the tensioner A2 of the second embodiment. In this embodiment, the protrusion 52 extending integrally from the spacer body 51 to the outside is hollow, and the other configuration is the same as that shown in FIG. Thus, the whole spacer 5 can be made lightweight by making the projection part 52 hollow.

  FIG. 8 shows a third form of the spacer 5 used in the tensioner A2 of the second embodiment. The spacer 5 of this form is integrally formed by connecting the spacer main body 51 and the protrusion 52 continuously. Thereby, there is an advantage that the spacer 5 can be further reduced in weight.

  FIG. 9 shows a fourth form of the spacer 5 used in the tensioner A2 of the second embodiment. In this embodiment, the protrusion 52 is not provided at substantially the entire length in the length direction of the spacer body 51, but extends from the rear end side that is a part of the spacer body 51 in the length direction. Even in this case, the rear end portion 52b of the protrusion 52 extends in the direction of the other end portion 42 of the spring 4, and the extension amount of the rear end portion 52b is set to an amount corresponding to the plate thickness of the washer 8. Accordingly, the rear end portion 52b can be brought closer to the other end portion 42 of the spring 4, and accordingly, the displacement movement of the other end portion 42 of the spring 4 can be restricted. In the spacer 5 having the structure shown in FIG. 9, since the protrusion 52 is formed in a part of the spacer body 51 in the length direction, the material for forming the spacer 5 is reduced correspondingly, and the material cost can be reduced. it can.

(Third embodiment)
10 to 12 show a tensioner A3 according to a third embodiment of the present invention. Also in this embodiment, the first shaft member 2 and the second shaft member 3 are housed in the main body 11 of the case 1 in a screwed state, and the spring 4 made of a spring is housed in the main body 11. The case 1 is formed by aluminum die casting. A pair of slits 6 are formed in the main body 11 of the case 1. Each slit 6 is provided over the entire length of the main body 11. The slit 6 has the same draft angle during die casting, and gradually becomes wider toward the tip side (the tip side in the length direction of the shaft members 2 and 3). The other end 42 of the spring 4 is extracted and locked in the slit 6.

  In this embodiment, the spacer 5 is formed integrally with a cylindrical spacer main body 51, a protrusion 52 extending radially outward from the spacer main body 51, and a rear end portion in the length direction of the spacer main body 51. The bottom plate portion 53 is formed. As in the second embodiment, the spacer body 51 surrounds the first shaft member 2 and the second shaft member 3 that are screwed together, and prevents the shaft members 2 and 3 from coming out of the case 1. ing.

  The protrusion 52 has substantially the same length as the spacer body 51. Similar to the protrusion of the second embodiment, the protrusion 52 is inserted into the slit 6 of the case 1 so that the front end 52 a faces the bearing 7 and the rear end 52 b faces the other end 42 of the spring 4. This restricts the other end 42 of the spring 4 from moving in the slit 6.

  The bottom plate portion 53 is formed at the rear end portion in the length direction of the spacer body 51 so as to extend inward. The bottom plate portion 53 is formed so as to correspond to the small-diameter continuous portion 24 of the first shaft member 2, and a through hole 53a through which the small-diameter continuous portion 24 passes is formed. When the continuous portion 24 penetrates, the bottom plate portion 53 enters the axial gap 54 between the first shaft member 2 and the second shaft member 3 as shown in FIG. That is, the bottom plate portion 53 enters between the end surface (upper end surface) of the rear end portion 22 of the first shaft member 2 and the rear end surface 33 of the second shaft member 3. In the state of entering the gap 54, the bottom plate portion 53 contacts the large-diameter rear end portion 22 of the first shaft member 2.

  In this embodiment, when the length of the continuous portion 24 of the first shaft member 2 is d1, and the plate thickness of the bottom plate portion 53 entering the gap 54 is d2, the plate thickness of the bottom plate portion 53 so that d1> d2. Is set. When the plate thickness of the bottom plate portion 53 is set in this way, the second shaft member 3 is retracted to the maximum and the rear end surface 33 of the second shaft member 3 comes into contact with the continuous portion 24 of the first shaft member 2. Even so, the bottom plate portion 53 is sandwiched between the rear end portion 22 of the first shaft member 2 and the rear end surface 33 of the second shaft member 3 without the rear end surface 33 of the second shaft member 3 contacting the bottom plate portion 53. There is nothing. Thereby, the spacer 5 does not stick due to the pinching, and the spacer 5 can function reliably. Further, the bottom plate portion 53 prevents the spring 4 from being lifted in the same manner as the washer 8, so that the washer 8 can be omitted. As a result, the number of parts can be reduced.

(Fourth embodiment)
FIG. 13 shows a tensioner A4 according to a fourth embodiment of the present invention. Also in this embodiment, the first shaft member 2 and the second shaft member 3 are housed in the main body 11 of the case 1 in a screwed state, and the spring 4 made of a spring is housed in the main body 11. The case 1 is formed by aluminum die casting. A pair of slits 6 are formed in the main body 11 of the case 1. Each slit 6 is provided over the entire length of the main body 11. The slit 6 has the same draft angle during die casting, and gradually becomes wider toward the tip side (the tip side in the length direction of the shaft members 2 and 3). The other end 42 of the spring 4 is extracted and locked in the slit 6.

  As in the third embodiment, the spacer 5 in this embodiment is integrally extended to the outer side of the spacer main body 51 and the spacer main body 51 surrounding the outer periphery of the first shaft member 2 and the second shaft member 3 in the screwed state. It has a protrusion 52 that is in contact with and inserted into the slit 6 of the case 1 and a bottom plate 53 that is integrally formed at the rear end of the spacer body 51 in the length direction. The bottom plate portion 53 is formed so as to extend inward from the rear end portion in the length direction of the spacer main body 51 as in the third embodiment. By forming the bottom plate portion 53, the washer 8 becomes unnecessary, and the number of parts can be reduced.

  In this embodiment, the cap 10 is caulked and fixed to the distal end portion of the second shaft member 3, but the cap 10 has a distal end surface 25 of the first shaft member 2 when the second shaft member 3 is retracted to the maximum. It comes to contact with. When the cap 10 abuts on the front end surface 25 of the first shaft member 2, the second shaft member 3 does not retreat further.

  In this embodiment, the size of the gap 54 between the rear end surface 33 of the second shaft member 3 and the rear end portion 22 of the first shaft member 2 when the second shaft member 3 is retracted to the maximum is the bottom plate portion 53 of the spacer 5. It is set to be larger than the plate thickness. By setting in this way, even if the second shaft member 3 is retracted to the maximum, the rear end surface 33 of the second shaft member 3 does not contact the bottom plate portion 53 and the bottom plate portion 53 is moved to the first shaft member. 2 between the rear end portion 22 and the rear end surface 33 of the second shaft member 3. As a result, as in the third embodiment, the spacer 5 does not stick due to pinching, and the spacer 5 can function reliably.

  In the above embodiment, a spring is used as the spring 4, but a torsion spring can be used. In this case, one end of the torsion spring is locked to the first shaft member 2 and the other end is locked to the slit 6 of the case 1 so that the first shaft member 2 can be urged to rotate.

A1, A2, A3, A4 Tensioner 1 Case 2 First shaft member 3 Second shaft member 4 Spring 5 Spacer 6 Slit 8 Washer 9 Movement restricting member 10 Cap 21 Male thread part 31 Female thread part 41 One end part 42 of spring The other end of the spring Portion 51 Spacer 52 Protrusion 53 Bottom plate 54 Clearance 61 Inner edge 62 Outer edge

Claims (6)

A first shaft member and a second shaft member that are screwed together by a screw portion, and a spring that rotationally biases the first shaft member are housed in a case, and the first shaft member and the second shaft member that are screwed together Spacers are provided around the outside of the first shaft member and the second shaft member to prevent the second shaft member from coming out from the case, and the rotation biasing force of the spring is controlled by restricting the rotation of the second shaft member. A tensioner that transforms into the driving force of
One end of the spring is locked to the first shaft member, the other end is locked to a slit formed in the length direction of the case, and the length direction of the slit at the other end of the spring A tensioner, wherein a movement restricting member for restricting movement to the slit is inserted into the slit.   The movement restricting member is formed by a main body portion that is inserted into the slit, and an engaging convex portion that is integrally formed with the main body portion and engages with an inner edge portion and an outer edge portion of the slit. The tensioner according to claim 1, wherein   2. The tensioner according to claim 1, wherein the movement restricting member includes a protruding portion formed so as to integrally extend outward from the spacer, and the protruding portion is inserted into the slit.   A bottom plate portion extending inward is formed at a rear end portion in the length direction of the spacer, and the bottom plate portion enters an axial gap between the first shaft member and the second shaft member. The tensioner according to claim 1 or 3.   5. The tensioner according to claim 4, wherein a size of the gap when the second shaft member is retracted to a maximum is larger than a thickness of the bottom plate portion.   When the second shaft member is retracted to the maximum, a cap that contacts the first shaft member is attached to a longitudinal end of the second shaft member, and the cap contacts the first shaft member. The tensioner according to claim 4, wherein a dimension of the gap is larger than a thickness of the bottom plate portion.

Images