WO2017217384A1

WO2017217384A1 - Tensioner

Info

Publication number: WO2017217384A1
Application number: PCT/JP2017/021709
Authority: WO
Inventors: 山田　佳男; 壮一中山; 貴雄小林
Original assignee: 日本発條株式会社
Priority date: 2016-06-13
Filing date: 2017-06-12
Publication date: 2017-12-21
Also published as: JP6818025B2; JPWO2017217384A1

Abstract

Provided is a tensioner in which the number of parts is reduced to simplify the structure and which can be easily assembled. This tensioner is provided with: a first shaft member (3) affixed to a support member (2) in a non-rotatable state; a second shaft member (4) which is mounted to the first shaft member (3) while being engaged therewith by threads and which advances axially to directly or indirectly press a counterpart-member (340); and a spring (5) for applying rotational force to the second shaft member (4). The rotational force applied to the second shaft member (4) by the spring (5) rotates and advances the second shaft member (4) to press the counterpart-member (340).

Description

Tensioner

The present invention relates to a tensioner used to keep the tension of a mating member such as an endless belt or chain constant, and more particularly to a tensioner that can have a simple structure with a reduced number of parts.

A tensioner is used for an engine of a motor vehicle such as a two-wheeled vehicle or a four-wheeled vehicle. For example, when a timing chain or a timing belt of an engine is pushed with a predetermined force, the tensioner is elongated or loosened. , Acts to keep the tension constant.

FIG. 52 shows a state in which the tensioner 200 is mounted on the engine body 300 of the automobile. A pair of cam sprockets 310 and a crank sprocket 320 are arranged inside the engine body 300, and a timing chain 330 is stretched between these sprockets 310 and 320 in an endless manner. A chain guide 340 is swingably disposed on the moving path of the timing chain 330, and the timing chain 330 moves while sliding on the chain guide 340. The tensioner 200 is fixed to the engine main body 300 in a state where the engine main body 300 is inserted so as to pass through a mounting hole 360 formed in the engine main body 300.

In the tensioner, conventionally, the first shaft member and the second shaft member are assembled by the screw portion and accommodated in the case, the first shaft member is rotationally biased by the spring, and the second shaft member is propelled by this rotational force. It has a structure (see, for example, Patent Document 1).

FIG. 53 shows the structure of the conventional tensioner 200 described above. A cylindrical second shaft member 210, a first shaft member 230 screwed into the second shaft member 210 by a screw portion 220, a spring 240 such as a coil spring that applies rotational torque to the first shaft member 230, and these The case 250 is fixed to the engine main body 300 by bolting or the like. The rotation of the second shaft member 210 is restricted by a bearing 260 attached to the tip portion of the case 250. The bearing 260 has a non-circular sliding hole 261 that is oval or parallel cut, and the rotation of the second shaft member 210 is restricted by passing through the sliding hole 261. Therefore, the first shaft member The rotational force 230 is converted into linear motion, and the second shaft member 210 advances linearly. The case 250 is provided with a dish-shaped shaft receiver 270, and the base end portion of the first shaft member 230 is inserted into the shaft receiver 270.

In such a tensioner 200, the second shaft member 210 moves forward with respect to the case 250 by the rotational force of the first shaft member 230 transmitted through the threaded portion 220, and causes the chain guide 340 (that is, the timing chain 330) to move. Press. On the other hand, when the tension of the timing chain 330 increases, the second shaft member 210 moves backward while rotating the first shaft member 230 in the reverse direction. By these operations, the tension of the timing chain 330 can be kept constant.

Japanese Patent No. 4521624

In the conventional tensioner 200, the shaft receiver 270 and the bearing 260 are provided in the case 250. Since the shaft receiver 270 needs to support the first shaft member 230 in a rotatable manner, the bearing 260 is provided because it is necessary to convert the rotational force of the first shaft member 230 into the propulsive force of the second shaft member 210. .
Thus, in the conventional tensioner, the shaft receiver 270 for rotatably supporting the first shaft member and the bearing 260 for causing the second shaft member to linearly advance are required. Further, a case 250 for attaching them is also required. As a result, the conventional tensioner has a large number of parts, a complicated structure, and troublesome assembly.
The present invention has been made in view of such conventional problems, and an object of the present invention is to provide a tensioner that can greatly reduce the number of parts, simplify the structure, and can be easily assembled.

The tensioner according to the present invention includes a first shaft member fixed to a support member in a non-rotating state, and is attached to the first shaft member in a screwed state. A second shaft member that presses and a spring that directly applies a rotational force to the second shaft member, and the second shaft member advances while rotating by the rotational force applied by the spring and moves the counterpart member It is characterized by pressing.

In the present invention, the advancement of the second shaft member is supported only in a state where the second shaft member is screwed to the first shaft member.
The present invention further includes a cap that is directly or indirectly in contact with the tip surface of the second shaft member and is rotatable with respect to the second shaft member, and the cap abuts against the counterpart member. What
In addition, an average contact diameter at which the second shaft member and the mating member or the second shaft member and the cap are in contact with each other is set according to the advancement dimension of the second shaft member.
The spring is a torsion spring having one end locked to the first shaft member and the other end locked to the second shaft member.
Further, the spring is a mainspring spring having one end locked to the first shaft member and the other end locked to the second shaft member.
Furthermore, in the present invention, the rear end portion is engaged with the support member or the first shaft member to be rotationally restricted, and the front end portion is directly or indirectly engaged with the second shaft member to be second. A stopper member that locks the rotation of the shaft member is inserted in the axial direction of the second shaft member so as to be removable.
Further, a stopper member that removably engages with the second shaft member and locks the movement of the second shaft member in the axial direction is detachable from the support member or the first shaft member.

Another tensioner according to the present invention includes a first shaft member fixed to a support member in a non-rotating state, and is attached to the first shaft member in a screwed state. A second shaft member that presses and a spring that imparts a rotational force to the second shaft member, and the second shaft member advances while rotating by the rotational force imparted by the spring to move the counterpart member The connector member is configured to be pressed, and a connector member that is rotatable in a state in which axial movement is constrained is disposed in a state of being engaged with the spring and the second shaft member, and the second shaft member includes the connector member. And advancing in the axial direction by applying a rotational force of the spring.

In the present invention, the spring is a mainspring spring having one end locked to the first shaft member or the support member and the other end locked to the connector member.
In the present invention, the stopper member that engages with the connector member and locks the rotation of the connector member is attachable to and detachable from the support member or the first shaft member.
In addition, a cap that is rotatable with respect to the second shaft member is attached in contact with the distal end surface of the second shaft member.
Furthermore, the connector member and the second shaft member are formed with a rotational force transmitting means for transmitting the rotational force by engaging with each other.
Further, the second shaft member advances in the axial direction while the rotational force transmitting means is engaged with each other.
Further, the rotational force transmitting means is engaged with a sliding surface portion formed along the axial direction of the second shaft member so as to face the sliding surface portion, and the sliding surface portion slides in the engaged state. It is formed by the facing nail | claw part formed in the said connector member so that it may move.

In the tensioner of the present invention, the first shaft member is fixed to the support member in a non-rotating state, and the second shaft member is advanced while rotating with the spring force of the spring while being screwed to the first shaft member. Press the member. Accordingly, since the first shaft member does not rotate, a shaft receiver for supporting the rotation of the first shaft member becomes unnecessary. Further, since the second shaft member advances while rotating, it is not necessary to restrict the rotation, and a bearing for restricting the rotation of the second shaft member becomes unnecessary. Since the shaft receiver and the bearing are unnecessary, a case for attaching them is also unnecessary, the number of parts is greatly reduced, the structure is simple, the assembly is easy, and the weight can be reduced.

Also in another tensioner of the present invention, the first shaft member is fixed to the support member in a non-rotating state, and the second shaft member is screwed to the first shaft member. Since the rotational force of the spring is transmitted to the second shaft member via the connector member, the second shaft member advances while rotating and presses the mating member. As described above, since the first shaft member does not rotate, a shaft receiver for supporting the rotation of the first shaft member becomes unnecessary. Further, since the second shaft member advances while rotating, it is not necessary to restrict the rotation, and a bearing for restricting the rotation of the second shaft member becomes unnecessary. Since the shaft receiver and the bearing are unnecessary, a case for attaching them is also unnecessary, the number of parts is greatly reduced, the structure is simple, the assembly is easy, and the weight can be reduced.

FIG. 4 is a cross-sectional view from the right side surface of the tensioner according to the first embodiment of the present invention, and is a cross-sectional view taken along line E6-E6 in FIG. It is a side view from the left side of the tensioner of 1st Embodiment of this invention. FIG. 2 is a cross-sectional view taken along line E1-E1 in FIG. It is sectional drawing which shows the pressing state of the tensioner of 1st Embodiment. (A) and (B) are a side view and a sectional view taken along line E2-E2 of the support member. (A), (B) is a front view of the first shaft member and a sectional view taken along line E3-E3. (A), (B), (C) is the front view, side view, and E4-E4 sectional view of the second shaft member. (A), (B), (C) is the left view of a spring, a front view, and a right view. (A), (B) is the front view and right view of a stopper member. It is sectional drawing which shows the tensioner of the modification of 1st Embodiment. It is sectional drawing which shows the tensioner of another modification of 1st Embodiment. It is sectional drawing which shows the tensioner of another modification of 1st Embodiment. It is sectional drawing which shows the modification of 1st Embodiment. It is a side view from the right side of the tensioner of 2nd Embodiment of this invention. It is a side view from the left side of the tensioner of 2nd Embodiment of this invention. It is F1-F1 sectional view taken on the line of FIG. It is an expanded sectional view which shows the principal part of FIG. (A), (B) is a side view which shows the action | operation of the stopper member in the tensioner of 2nd Embodiment. It is sectional drawing which shows the press state of the tensioner of 2nd Embodiment. It is an expanded sectional view which shows the principal part of FIG. (A), (B) is a side view of a second shaft member used in the second embodiment, and is a cross-sectional view taken along line F2-F2. (A) and (B) are the side view and longitudinal cross-sectional view which show a coupling. It is a side view which shows a cap. (A), (B) is the front view which shows a retaining ring, and a longitudinal cross-sectional view. It is the front view and right view of a stopper member used for 2nd Embodiment. It is a side view from the right side of the tensioner of 3rd Embodiment of this invention. It is a side view from the left side of the tensioner of 3rd Embodiment. FIG. 27 is a sectional view taken along line G1-G1 in FIG. It is an expanded sectional view which shows the principal part of FIG. (A), (B) is an end elevation which shows the action | operation of the stopper member of 3rd Embodiment. It is a side view from the right side of the tensioner of 4th Embodiment of this invention. FIG. 34 is a cross-sectional view of the tensioner of the fourth embodiment taken along the line H2-H2 in FIG. FIG. 32 is a cross-sectional view taken along line H1-H1 of FIG. 31 and shows a temporarily locked state of the tensioner of the fourth embodiment. It is sectional drawing which shows the press state in the tensioner of 4th Embodiment. It is an expanded sectional view of the tensioner press state of a 4th embodiment. (A) and (B) are a side view and a sectional view taken along line H3-H3 of a supporting member used in the fourth embodiment. (A), (B) is the front view and right view of a 2nd shaft member which are used for 4th Embodiment. (A), (B) is the front view and H4-H4 sectional view of the 1st shaft member used for 4th Embodiment. (A), (B), (C) is the left view, front view, and right view of the spring used for 4th Embodiment. (A), (B) is the left view of the cap used for 4th Embodiment, and a partially broken sectional view. (A), (B) is the front view and right view which show the stopper member used for 4th Embodiment. FIG. 44 is a cross-sectional view taken along line M2-M2 in FIG. 43, showing a temporarily locked state of the tensioner according to the fifth embodiment of the present invention. FIG. 43 is a sectional view taken along line M1-M1 in FIG. 42 of the fifth embodiment. FIG. 46 is a cross-sectional view taken along line M3-M3 in FIG. 45, showing the unlocked state of the fifth embodiment. It is a longitudinal cross-sectional view which shows the lock release state of 5th Embodiment. (A) and (B) are a side view and a sectional view taken along line M4-M4 of a supporting member used in the fifth embodiment. (A), (B) is the left view and front view of a 1st shaft member which are used for 5th Embodiment. (A), (B) is the partially broken cross section and right view of the 2nd shaft member used for 5th Embodiment. (A), (B), (C), (D) is the left view, right view, top view, and partial fracture | rupture sectional view which show the connector member used for 5th Embodiment. (A), (B) is the side view and partially broken sectional view of the cap used for 5th Embodiment. (A), (B) is the top view and front view of the stopper member which are used for 5th Embodiment. It is a side view which shows the state which assembled | attached the tensioner to the engine main body. It is sectional drawing which shows the conventional tensioner.

Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments. In addition, in each embodiment, the same code | symbol is attached | subjected to the same member and it is made to respond | correspond. The tensioner of the present invention has a structure in which the case for housing the component parts is omitted, and the number of parts is reduced by directly attaching to the engine body with this structure.

[First Embodiment]
1 to 12 show a tensioner 1 according to a first embodiment of the present invention, FIGS. 1 to 4 show the entire tensioner 1, FIGS. 5 to 9 show respective components, and FIGS. 10 to 12 show modified examples. It is. 1 and 2 are a sectional view and a left side view of the tensioner 1 taken along line E6-E6 in FIG. 3, FIG. 3 is a sectional view taken along line E1-E1 in FIG. 1, and FIG. The figure is shown. The tensioner 1 is formed by a support member 2, a first shaft member 3, a second shaft member 4, a spring 5, and a stopper member 6.

The support member 2 serves as an attachment member when attaching the tensioner 1 to the engine body 300 (see FIG. 52). The support member 2 supports the first shaft member 3. As shown in FIGS. 1 to 3 and 5, the support member 2 includes a cloud-shaped flat plate-like flange portion 21 and a fixing portion 22 formed on the flange portion 21. The flange portion 21 is a portion that is fixed to the engine main body 300 with a bolt or the like, and mounting hole portions 24 through which the bolt penetrates are formed at two positions sandwiching the fixing portion 22.

The fixing portion 22 is a portion that fixes the first shaft member 3 in a rising shape, and is formed in a rising shape in a short cylindrical shape at the center portion of the flange portion 21. The first shaft member 3 can be fixed upright by inserting the fixing portion 22 into the rear end portion of the first shaft member 3 and crimping the fixing portion 22 in this inserted state (see FIG. 3). The fixing portion 22 which is in the shape of a short cylinder has an operation hole portion 23. The operation hole 23 is for inserting a stopper member 6 described later. Further, as shown in FIG. 5, a rotation stop convex portion 25 is formed on the rear end surface of the flange portion 21. The rotation prevention convex part 25 is for preventing rotation of the stopper member 6 described later.

As shown in FIGS. 3 and 6, the first shaft member 3 is formed of a cylindrical body having a predetermined length. The first shaft member 3 is directly fixed to the fixing portion 22 of the support member 2 in a non-rotating state. A male screw portion 31 is formed on the outer surface of the first shaft member 3, and a second shaft member 4 described later can be screwed together. At the rear end portion (left end portion in FIG. 6) of the first shaft member 3, a caulking portion 32 to which the fixing portion 22 of the support member 2 is caulked is formed so as to protrude inward, and this caulking portion The first shaft member 3 is fixed directly to the support member 2 by 32 in a non-rotating state. Further, a hook hole 33 in which one end of the spring 5 is locked is formed in a portion close to the rear end portion.

In the present invention, the structure for fixing the first shaft member 3 to the support member 2 may be other than the illustrated structure. For example, the caulking portion at the rear end portion of the first shaft member 3 may be formed so as to protrude outward, and the fixing portion 22 of the flange portion 21 of the support member 2 may be caulked with respect to the caulking portion. Further, the rear end portion of the first shaft member 3 may be fixed to the flange portion 21 of the support member 2 with a screw, and the rear end portion of the first shaft member 3 is fixed to the flange portion 21 of the support member 2 by spot welding. You may do it. Furthermore, it is also possible to form a screw portion that is screwed to the rear end portion of the first shaft member 3 and the fixing portion 22 of the flange portion 21 of the support member 2 and to fix the screw portion by joining them.

The second shaft member 4 advances in the axial direction to press the chain guide 340 (timing chain 330) as a counterpart member (see FIG. 4). As shown in FIGS. 3, 4, and 7, the second shaft member 4 is formed by a cylindrical body 41 that is open at the rear end side (left end side in FIG. 7) and sealed at the front end side by a head portion 42. Yes. The front end surface of the head portion 42 becomes a contact surface 44 that directly contacts the mating member (chain guide 340 in FIG. 4).

On the inner surface of the cylindrical body 41, a female screw portion 43 that is screwed into the male screw portion 32 of the first shaft member 3 is formed. On the opposite side of the head portion 42 from the contact surface 44, an engagement hole 45 that engages with the stopper member 6 when the distal end portion of the stopper member 6 is inserted is formed. The engagement hole 45 is formed as a non-circular hole (square hole in the illustrated example) and engages with the stopper member 6. Further, a hook hole 46 in which the other end of the spring 5 is locked is formed on the outer surface on the distal end side of the cylindrical body 41.

The second shaft member 4 described above rotates when the spring force of the spring 5 acts. At this time, since the second shaft member 4 is screwed into the first shaft member 3, the second shaft member 4 advances in the axial direction of the first shaft member 3 while rotating. That is, the second shaft member 4 is supported by the first shaft member 3 only when the female screw 43 is screwed into the male screw 32 of the first shaft member 3. And it advances, rotating in the support state of this 1st shaft member 3. As shown in FIG. When the second shaft member 4 has a reaction force greater than the set value from the counterpart member, the second shaft member 4 moves backward while rotating in the reverse direction. Note that the second shaft member 4 does not retreat with a reaction force less than the setting.

3 and 4, the spring 5 is disposed outside the second shaft member 4. As the spring 5, a torsion spring in which

hook portions

52 and 53 are formed at both ends of a coil portion 51 as shown in FIG. 8 is used. In the torsion spring 5, the coil portion 51 is extrapolated to the second shaft member 4, and the hook portion 52 at one end is locked in the hook hole 33 of the first shaft member 3 in this extrapolated state, and the hook portion 53 at the other end. Is locked in the hook hole 46 of the two shaft member 4. The torsion spring is in a state in which the rotational force by which the second shaft member 4 rotates is stored, and the tensioner 1 is set in the engine body 300 in this state.

The stopper member 6 temporarily locks the rotation of the second shaft member 4. This temporary lock is performed before the tensioner 1 is attached to the engine main body 300, and the temporary lock is released after the tensioner 1 is attached to the engine main body 300. As shown in FIG. 9, the stopper member 6 has a thin plate shape with a rectangular cross section, and is formed so that the length direction is T-shaped. The stopper member 6 includes a stopper main body 61 extending in the axial direction of the second shaft portion 4, a first engaging portion 62 at the rear end (left end in FIG. 9) of the stopper main body 61, and a front end (FIG. 9). Right engaging portion) of the second engaging portion 63. The stopper main body 61 is inserted into the second shaft member 4 from the operation hole 23 of the support member 2.

The first engaging portion 62 of the stopper member 6 enters and engages between the rotation preventing convex portions 25 formed on the flange portion 21 of the support member 2. This engagement restricts the rotation of the stopper member 6. The second engagement portion 63 engages with the engagement hole 45 of the second shaft member 4. In the state where the second engaging portion 63 is engaged, the rotation of the second shaft member 4 is temporarily locked. The temporary lock is released by pulling out the stopper member 6 from the second shaft member 4 and releasing the engagement of the second engagement portion 63.

In FIG. 3, the stopper member 6 is inserted into the second shaft member 4 from the operation hole portion 23 of the support member 2, so that the second engagement portion 63 of the stopper member 6 becomes the engagement hole 45 of the second shaft member 4. A state is shown in which the first engagement portion 62 is engaged with the rotation-preventing convex portion 25 of the support member 2. The rotation of the second shaft member 4 is temporarily locked by the engagement of these stopper members 6, and the second shaft member 4 does not rotate and advance. In this temporarily locked state, the tensioner 1 is attached and fixed to the engine main body 300. The attachment to the engine body 300 is performed by bolting the flange portion 21 of the support member 2.

FIG. 4 shows a state where the stopper member 6 is pulled out from the tensioner 1 after the tensioner 1 is attached to the engine body 300. Since the temporary lock by the stopper member 6 is released by pulling out the stopper member 6, the second shaft member 4 advances in the axial direction while being rotated by the rotational force of the spring 5 in a state of being screwed to the first shaft member 3, The chain guide 340 is pressed by the contact surface 44. Thereby, the tension of the timing chain 330 can be applied. On the other hand, when the vibration (input load) from the engine is large and a tension higher than the set value is generated in the timing chain 330, the second shaft member 4 moves backward in the axial direction while rotating in the reverse direction.

In the tensioner 1 of the above embodiment, the second shaft member 4 screwed to the first shaft member 3 advances in the axial direction while rotating by the rotational force from the spring 5 to press the mating member (chain guide 340). Since the tension is applied to the timing chain 330, the tension of the timing chain 330 can be kept constant. In the tensioner 1 having this structure, the first shaft member 3 is directly fixed to the support member 2 in a non-rotating state, and the spring force of the spring 5 is obtained while the second shaft member 4 is screwed to the first shaft member 3. Rotate to advance and press the mating member. In such a structure, since the first shaft member does not rotate, a shaft receiver for supporting the rotation of the first shaft member becomes unnecessary. Further, since the second shaft member advances while rotating, it is not necessary to restrict the rotation, and a bearing for restricting the rotation of the second shaft member becomes unnecessary. Thus, since the shaft receiver and the bearing are not necessary, a case for attaching them is not necessary, and a caseless tensioner can be obtained. Accordingly, the tensioner can be easily assembled and reduced in weight with a simple structure by greatly reducing the number of parts.

Next, a design example of the tensioner 1 will be described. In FIG. 4, φD is a contact diameter (contact average diameter) between the contact surface 44 of the second shaft member 4 and the receiving surface 344 of the chain guide 340. Here, a convex receiving portion 341 is formed on the chain guide 340, and the receiving surface 344 of the chain guide 340 is a surface facing the second shaft member 4 in the receiving portion 341.
The tensioner 1 of the present embodiment has the above-described structure, so that the following three torques act, and the advancement dimension (protrusion dimension) of the second shaft member 4 is determined by the balance of these torques.
Torque 1... Second shaft member generated in the threaded portion (the male threaded portion 31 and the female threaded portion 43) when engine vibration (alternate load) accompanying the fluctuation in the tension of the timing chain 330 is input to the second shaft member 4. 4 Rotational torque in the backward (return) direction Torque 2... Resistance torque of sliding friction caused by the contact surface 44 of the rotating second shaft member 4 sliding on the receiving surface 344 of the chain guide 340 Torque 3.・ Torque in the advancing direction of the second shaft member biased by the spring 5

Of the above three torques, when the torque 2 is small, the starting position of the second shaft member 4 tends to retreat, and when the torque 2 is large, the second shaft member 4 tends to advance. The torque 2 is determined by the contact diameter (contact average diameter) φD of the second shaft member 4. Therefore, it is possible to adjust the allowance dimension (advance dimension) of the second shaft member 4 by appropriately selecting the contact diameter (contact average diameter) φD depending on the strength of the engine vibration.

10 to 12 show modifications of the present embodiment.
The tensioner 1 of the modified example shown in FIG. 10 is such that the contact surface 44 at the tip of the second shaft member 4 is tapered and contacts the receiving surface 344 of the chain guide 340, thereby reducing the contact diameter φD. It becomes possible.
The tensioner 1 of the modified example shown in FIG. 11 is such that the receiving surface 344 of the chain guide 340 is tapered to contact the contact surface 44 of the second shaft member 4, and the contact diameter φD can be similarly reduced. Become.
The tensioner 1 of the modified example shown in FIG. 12 is configured such that a rotating piece 343 is rotatably attached to a receiving portion 341 of a chain guide 340 and the rotating piece 343 and the contact surface 44 of the second shaft member 4 are brought into contact with each other. The rotating piece 343 operates to receive the pressing force of the second shaft member 4 while rotating between the second shaft member 4 and the chain guide 340. By providing the rotating piece 343, the contact diameter φD can be adjusted without the second shaft member 4 rubbing directly with the chain guide 340.

FIG. 13 shows a tensioner 1 according to a modification of this embodiment. In the tensioner 1 of this form, the mainspring spring 55 is used as a spring that applies a rotational force to the second shaft member 4. The mainspring spring 55 is a spring formed by winding a thin plate material having spring properties in a spiral shape, and restoring force is accumulated by winding up, and a rotational force is applied to the second shaft member 4 by this restoring force. The mainspring spring 55 has a spiral spring main body portion 56 and one end portion 57 and the other end portion 58 which are both ends of the spring main body portion 56, and the spring main body portion 56 is located on the rear side of the second shaft member 4. Extrapolated, one end 57 is locked to the first shaft member 3, and the other end 58 is locked to the second shaft member 4. By these locking, the mainspring spring 55 directly applies a rotational force to the second shaft member 4.

[Second Embodiment]
14 to 25 show a tensioner 1A according to a second embodiment of the present invention. FIGS. 14 to 17 show the entire tensioner 1A, FIGS. 18 to 20 show the operation of the tensioner 1A, and FIGS. The parts are shown.

In the tensioner 1A of the present embodiment, the support member 2, the second shaft member 4, and the stopper member 6 are changed with respect to the first embodiment. Further, a cap 7 is indirectly attached to the distal end portion of the second shaft member 4 via a coupling 8.
In the support member 2, the rotation prevention convex portion 25 in the flange portion 21 is formed at a position orthogonal to the rotation prevention convex portion 25 of the first embodiment, and the first engagement portion 62 of the stopper member 6 is rotated. It engages with the stop projection 25. Although the 1st shaft member 3 is being fixed by crimping the fixing | fixed part 22 from the flange part 21 of the supporting member 2 to the crimping part 32 of the rear end part, this fixation may be structures other than this. . For example, as in the first embodiment, the caulking portion at the rear end portion of the first shaft member 3 is formed so as to protrude outward, and the fixing portion of the flange portion 21 of the support member 2 with respect to the caulking portion. 22 may be crimped, the rear end portion of the first shaft member 3 may be fixed to the flange portion 21 of the support member 2 with a screw, and the rear end portion of the first shaft member 3 may be fixed by spot welding. The flange portion 21 may be fixed. Furthermore, it is also possible to form a screw portion that is screwed to the rear end portion of the first shaft member 3 and the fixing portion 22 of the flange portion 21 of the support member 2 and to fix the screw portion by joining them.

16 and 17, a cap 7 is attached to the distal end portion (the right end portion in FIGS. 16 and 17) of the second shaft member 4 via a coupling 8. The cap 7 is attached to the distal end portion of the second shaft member 4 via the coupling 8. The cap 7 indirectly contacts the second shaft member 4 through the coupling 8.

As shown in FIGS. 17 and 22, the coupling 8 includes a leg 81 at the rear end (left end in FIG. 22) and a coupling main body 82 formed integrally with the leg 81. It is formed in a short cylinder shape. In the coupling 8, the leg 81 at the rear end is inserted into the tip of the second shaft member 4, and in this inserted state, the stopper pin 9 made of a split pin is inserted in a direction crossing the axial direction, and the second shaft member 4. And it is attached to the front-end | tip part of the 2nd shaft member 4 by making it penetrate the leg part 81. As shown in FIG. Thereby, the coupling 8 rotates integrally with the second shaft member 4.

In order to correspond to this coupling 8, as shown in FIGS. 17, 20, and 21, the cylindrical portion 41 of the second shaft member 4 has a shape in which the head portion 42 of the first embodiment is deleted. . A pin hole 47 into which the stopper pin 9 is inserted is formed in the cylindrical portion 41 of the second shaft member 4.

As shown in FIGS. 16, 17, and 23, the cap 7 includes a cap main body 71 that covers the tip of the coupling 8, and a leg 72 that extends rearward from the cap main body 71. 72 is inserted so as to penetrate the coupling main body 82. A ring-shaped retaining groove 73 is formed in the leg portion 72, and the cap 7 is coupled to the coupling 8 by attaching the retaining ring 10 to the retaining groove 73 of the leg portion 72 penetrating the coupling body portion 82. It is rotatably attached to the tip of the. As the retaining ring 10, a C-ring shown in FIG. 24 can be used. The cap 7 is rotatable at the distal end portion of the second shaft member 4 (that is, the distal end portion of the coupling 8). In this state, the contact surface 74 on the distal end side receives the receiving surface 345 of the receiving portion 341 in the chain guide 340. Contact with. In such a structure, the second shaft member 4 indirectly contacts the chain guide 340 via the cap 7 and presses the guide 340.

As shown in FIG. 25, the stopper member 6 has a thin plate shape with a rectangular cross section, and is formed so that the length direction is T-shaped. The stopper member 6 includes a stopper main body 61 extending in the axial direction of the second shaft member 4, a first engaging portion 62 at the rear end (left end in FIG. 25) of the stopper main body 61, and a front end (FIG. 25). Right engaging portion) of the second engaging portion 63. In the present embodiment, the second engaging portion 63 is formed in a bifurcated shape to form an engaging recess 64. The stopper member 9 is engaged with the second shaft member 4 by the stopper pin 9 entering the engaging recess 64.

The first engaging portion 62 of the stopper member 6 enters and engages between the rotation preventing convex portions 25 formed on the flange portion 21 of the support member 2. This engagement restricts the rotation of the stopper member 6. Further, when the stopper pin 9 enters the engaging recess 64 of the second engaging portion 63, the second engaging portion 63 engages with the second shaft member 4 via the stopper pin 9. In these engaged states, the rotation of the second shaft member 4 is temporarily locked. This temporary locking is achieved by pulling out the stopper member 6 from the second shaft member 4 and releasing the engagement of the second engaging portion 63 with the stopper pin 9 (see FIG. 18).

FIG. 16 shows the operation for the position where the second shaft member 4 is most retracted. The stopper member 6 is inserted into the second shaft member 4 to engage the engaging recess 64 at the tip with the stopper pin 9 and the rear. The first engaging portion 62 at the end is engaged with the rotation preventing convex portion 25 of the support member 2. As a result, the advancement of the second shaft member 4 is temporarily locked. In this state, the tensioner 1A is attached to the engine body 300. After this attachment, the stopper member 6 is pulled out to release the temporary lock.

When the temporary lock is released, the second shaft member 4 advances in the axial direction of the first shaft member 3 while rotating by the rotational force applied by the spring 5. At this time, the coupling 8 advances while rotating together with the second shaft member 4. FIG. 19 shows this state, and the cap 7 attached to the second shaft member 4 via the coupling 8 presses the guide 340 with the contact surface 74 at the tip contacting the receiving surface 345 of the chain guide 340. Thereby, tension can be applied to the timing chain 330.

In the tensioner 1 A of the present embodiment, the second shaft member 4 screwed into the first shaft member 3 advances in the axial direction while rotating by the rotational force from the spring 5, and the counterpart member (chain guide 340) via the cap 7. ) To apply tension to the timing chain 330, the tension of the timing chain 330 can be kept constant. In the tensioner 1 A having this structure, the first shaft member 3 is directly fixed to the support member 2 in a non-rotating state, and the spring force of the spring 5 with the second shaft member 4 screwed to the first shaft member 3. The cap 7 attached to the second shaft member 4 presses the mating member. In such a structure, since the first shaft member does not rotate as in the first embodiment, a shaft receiver for supporting the rotation of the first shaft member becomes unnecessary. Further, since the second shaft member advances while rotating, it is not necessary to restrict the rotation, and a bearing for restricting the rotation of the second shaft member becomes unnecessary. Thus, since the shaft receiver and the bearing are not necessary, a case for attaching them is not necessary, and a caseless tensioner can be obtained. Accordingly, the tensioner can be easily assembled and reduced in weight with a simple structure by greatly reducing the number of parts.

FIG. 20 shows a state in which the contact surface 74 of the cap 7 is in contact with the chain guide 340 (cap receiving surface 345 of the chain guide 340) as the second shaft member 4 advances. The contact average diameter φD is determined by the cap sliding surface 83 of the coupling 8 that rotates integrally with the second shaft member 4 and the coupling sliding surface 75 of the cap 7. The contact average diameter φD is calculated by (outer diameter of the contact surface on the sliding surface + inner diameter of the contact surface on the sliding surface) / 2. The average contact diameter φD is a parameter that determines the resistance torque of sliding friction caused by the sliding movement of the cap sliding surface 83 of the rotating coupling 8 on the coupling sliding surface 75 of the cap 7 (first). By adjusting this contact average diameter φD, the advance dimension (protrusion allowance) of the second shaft member 4 can be set similarly to the first embodiment.

In this embodiment, the contact area is determined by the guide contact surface 74 in which the cap 7 comes into contact with the cap receiving surface 345 of the chain guide 340 and the cap receiving surface 345 of the chain guide 340 in contact with the guide contact surface 74. By adjusting the contact area, the surface pressure applied to the cap receiving surface 345 of the chain guide 340 can be adjusted. In this case, the contact pressure of the cap receiving surface 345 of the chain guide 340 can be reduced by increasing the contact area.

[Third Embodiment]
26 to 30 show a tensioner 1B according to a third embodiment of the present invention, FIGS. 26 to 28 show the entire tensioner 1B, FIG. 29 shows a partially enlarged cross section, and FIG. 30 shows the operation of the stopper member.

In the tensioner 1B of the present embodiment, the support member 2, the stopper member 6, and the cap 7 are changed with respect to the second embodiment. Here, the first shaft member 3 is fixed by caulking the fixing portion 22 from the flange portion 21 of the support member 2 to the caulking portion 32 at the rear end thereof, but this fixing has a structure other than this. Also good. For example, as in the first embodiment, the caulking portion at the rear end portion of the first shaft member 3 is formed so as to protrude outward, and the fixing portion of the flange portion 21 of the support member 2 with respect to the caulking portion. 22 may be crimped, the rear end portion of the first shaft member 3 may be fixed to the flange portion 21 of the support member 2 with a screw, and the rear end portion of the first shaft member 3 may be fixed by spot welding. The flange portion 21 may be fixed. Furthermore, it is also possible to form a screw portion that is screwed to the rear end portion of the first shaft member 3 and the fixing portion 22 of the flange portion 21 of the support member 2 and to fix the screw portion by joining them.

In the tensioner 1B, the cap 7 is directly attached to the second shaft member 4 by inserting the leg portion 72 of the cap 7 into the distal end portion of the cylindrical portion 41 of the second shaft member 4 as shown in FIG. . At this time, by attaching the retaining ring 10 to the retaining groove 73 of the cap 7 and the retaining groove 48 of the second shaft member 4, the cap 7 does not fall out of the second shaft member 4, and the second shaft member 4 is not detached. Mounted rotatably.

In this embodiment, the rotation-preventing convex portion 25 is not formed on the flange portion 21 of the support member 2, and the first engagement portion 62 on the rear end side of the stopper member 6 is the flange portion 21 of the support member 2. The support member 2 is engaged by abutting against the support member 2. Thus, with respect to the state where the first engagement portion 62 of the stopper member 6 is engaged with the flange portion 21 of the support member 2, the stopper member 6 is moved relative to the second shaft member 4 by releasing the engagement. It can be rotated. The cap 7 is formed with an engagement hole portion 49 in which the second engagement portion 63 is engaged with the second engagement portion 63 at the distal end portion of the stopper member 6. As shown in FIG. 30, the engagement hole portion 49 is formed by a circular portion 49a and a cutout portion 49b in which a facing portion of the circular portion 49a is cut out linearly. The notch 49 b allows the second engaging portion 63 of the stopper member 6 to be inserted, and the circular portion 49 a prevents the second engaging portion 63 from coming off. This stopper prevents the stopper member 6 from being engaged with the cap 7. On the other hand, since the first engagement portion 62 of the stopper member 6 is engaged with the flange portion 21 of the support member 2, the stopper member 6 temporarily locks the movement of the second shaft member 4 through the cap 7. be able to. As in the first and second embodiments, the rotation prevention convex portion 25 is formed on the flange portion 21 of the support member 2, and the stopper member 6 is engaged with the rotation prevention convex portion 25 in the rotation prevention state. May be.

Also in the tensioner 1B of the present embodiment, the second shaft member 4 screwed into the first shaft member 3 advances in the axial direction while rotating by the rotational force from the spring 5, and the counterpart member (chain guide) is passed through the cap 7. 340) is pressed to apply tension to the timing chain 330, so that the tension of the timing chain 330 can be kept constant. Also in the tensioner 1B, the first shaft member 3 is directly fixed to the support member 2 in a non-rotating state, and the second shaft member 4 is rotated by a spring force while being screwed to the first shaft member 3. The cap 7 attached to the second shaft member 4 presses the mating member. In such a structure, as in the first embodiment and the second embodiment, the first shaft member does not rotate, so that a shaft receiver for supporting the rotation of the first shaft member is not necessary. Further, since the second shaft member advances while rotating, it is not necessary to restrict the rotation, and a bearing for restricting the rotation of the second shaft member becomes unnecessary. Thus, since the shaft receiver and the bearing are not necessary, a case for attaching them is not necessary, and a caseless tensioner can be obtained. Accordingly, the tensioner can be easily assembled and reduced in weight with a simple structure by greatly reducing the number of parts.

In this embodiment, the contact average diameter φD is determined by the cap sliding surface 401 of the second shaft member 4 with respect to the cap 7 and the shaft sliding surface 77 of the cap 7 with respect to the second shaft member 4. Further, the contact area is increased by the guide sliding surface 74 in which the cap 7 comes into contact with the cap receiving surface 345 of the chain guide 340 and the cap receiving surface 345 (see FIG. 20) of the chain guide 340 in contact with the guide sliding surface 74. It is determined. Therefore, similarly to the second embodiment, in this embodiment, the advance dimension (protrusion dimension) of the second shaft member 4 can be set by adjusting the contact average diameter φD. Further, by adjusting the contact area, the surface pressure applied to the cap receiving surface 345 of the chain guide 340 can be adjusted.

Various modifications can be made in the first to third embodiments described above.
For example, the stopper member 6 is rotationally restrained by engaging with the support member 2, but since the first shaft member 3 is attached to the support member 2 in a non-rotating state, the stopper member 6 is attached to the first shaft member 3. 6 may be engaged to restrict rotation. In addition, a spring 5 that applies a rotational force to the second shaft member 4 may be disposed inside the second shaft member 4 or inside the first shaft member 3. Further, the first shaft member 3 may be indirectly attached to the support member 2 via an intermediate member (not shown) such as a plate material to be in a non-rotating state.

[Fourth Embodiment]
FIGS. 31 to 41 show a tensioner 1C according to a fourth embodiment of the present invention. FIGS. 31 to 35 show the entire tensioner 1C, and FIGS. 36 to 41 show parts thereof. As shown in FIGS. 31 to 34, the tensioner 1C includes a support member 110, a first shaft member 120, a second shaft member 130, a spring 140, a stopper member 150, and a cap 160.

The support member 110 serves as an attachment member when the tensioner 1C is attached to the engine body 300 (see FIG. 52), and supports the first shaft member 120 in a non-rotating state. As shown in FIG. 31 to FIG. 34 and FIG. 36, the support member 110 has a cloud-shaped flat plate-like flange portion 111 and a fixing portion 112 formed on the flange portion 111. The flange portion 111 is a portion that is fixed to the engine main body 300 with a bolt or the like, and mounting hole portions 113 through which the bolt penetrates are formed at two positions sandwiching the fixing portion 112.

The fixing part 112 fixes the first shaft member 120 in a rising shape. The fixing portion 112 is formed in a cylindrical shape and recessed in the central portion of the flange portion 111, and the first shaft member 120 is inserted into the fixing portion 112 and fixed in a rising shape. The first shaft member 120 can be fixed by press-fitting the rear end portion (the left end portion in FIGS. 33 and 34) into the fixing portion 112 of the support member 110. Further, in addition to press-fitting, the fixing portion 112 may be caulked in the radial direction, thereby further reliably fixing. The first shaft member 120 can be fixed by means other than press fitting such as screwing, welding, and screwing. The bottom wall portion 115 of the cylindrical fixing portion 112 is formed with an exit hole portion 114 through which a stopper receiving portion 131 at the rear end portion of the second shaft member 130 described later is withdrawn.

As shown in FIGS. 33, 34 and 38, the first shaft member 120 is formed of a cylindrical body having a predetermined length, and has a cylindrical tubular main body 121. The first shaft member 120 is directly fixed to the fixing portion 112 of the support member 110 in a non-rotating state. That is, in the first shaft member 120, the rear end side (left end side) of the cylindrical main body 121 is a fixed cylindrical portion 122, and the fixed cylindrical portion 122 is press-fitted into the fixed portion 112 of the support member 110 or after press-fitting. It is fixed by tightening or the like. As a result, the first shaft member 120 is supported by the support member 110 in a non-rotating state.

The first shaft member 120 is formed with a female thread portion 123 for attaching the second shaft member 130 in a screwed state. The female screw portion 123 is formed on the inner surface on the distal end side (right end side) of the cylindrical tubular main body portion 121 with a predetermined length in the axial direction. A D-cut portion 124 is formed on the outer peripheral surface of the first shaft member 120 so that the one-side hook portion 141 of the spring 140 is locked. The D-cut portion 124 is formed in a hollow shape by cutting out a part of the outer peripheral surface of the first shaft member 120 in a straight line in a direction intersecting the axial direction, and the one-side hook portion of the spring 140 is formed in the D-cut portion 124. The one side hook part 141 of the spring 140 is latched by 141 entering (refer FIG. 32).

The second shaft member 130 advances in the axial direction to press the chain guide 340 (timing chain 330) as a counterpart member (see FIG. 34). As shown in FIGS. 33, 34 and 37, the second shaft member 130 has a stopper receiving portion 131, a shaft portion 132, and a cap mounting portion 133 from the rear end side (left end side) to the front end side (right end side). It is in the form of a solid shaft that is formed sequentially in the axial direction. The second shaft member 130 is inserted into the first shaft member 120 and advances in the axial direction while rotating while being inserted into the first shaft member 120.

A stopper receiving portion 131 of the second shaft member 130 is a portion with which a stopper member 150 to be described later is engaged, and is pulled out from a pull-out hole portion 114 of the support member 110, and the stopper member 150 is engaged in this pulled-out state. Since the stopper member 150 is engaged, a circumferential groove 134 is formed in the stopper receiving portion 131.
As shown in FIGS. 33 and 34, a stopper ring 138 is fixed to the stopper receiving portion 131 of the second shaft member 130. The retaining ring 138 is formed of a C ring or the like, and is fitted in a ring groove 139 (see FIG. 37) formed in the stopper receiving portion 131 of the second shaft member 13 so as to be positioned on the shaft portion 132 side with respect to the circumferential groove 134. . The retaining ring 138 contacts the thread of the female thread portion 123 of the first shaft member 120, and prevents the second shaft member 130 from coming out of the first shaft member 120 due to this contact.

The shaft portion 132 of the second shaft member 130 is a portion that is screwed into the female screw portion 123 of the first shaft member 120. The shaft portion 132 is elongated in the axial direction, and a male screw portion 135 is formed over the entire length of the outer peripheral surface, and the male screw portion 135 is screwed into the female screw portion 123 of the first shaft member 120. The second shaft member 130 is supported by the first shaft member 120 when the male screw portion 135 is screwed into the female screw portion 123 of the first shaft member 120, and advances in the axial direction while rotating in this supported state. On the other hand, when there is a reaction force greater than the set value from the counterpart member (chain guide 340), the second shaft member 130 moves backward in the axial direction while rotating in the reverse direction. Note that the second shaft member 130 does not retract with a reaction force less than the setting.

The cap attaching part 133 of the second shaft member 130 is a part for attaching a cap 160 described later. The cap attachment portion 133 is formed at the tip portion of the second shaft member 130 and indirectly presses the chain guide 340 as a counterpart member via the cap 160. Further, the cap mounting portion 133 is also a portion for locking the other hook portion 142 of the spring 140. For this reason, a slit-shaped slit groove 136 into which the other hook portion 142 of the spring 140 is inserted and locked is a shaft. It is formed along the direction.

The spring 140 applies a rotational force to the second shaft member 130. As shown in FIG. 39, the spring 140 is a torsion spring in which one side hook part 141 and the other side hook part 142 are formed at both ends of the coil part 143. In the spring 140 made of a torsion spring, the coil portion 143 is extrapolated to the first shaft member 120. In this extrapolated state, the one-side hook portion 141 is locked to the D-cut portion 124 of the first shaft member 120, and the other-side hook The portion 142 is locked to the slot groove 136 of the second shaft member 130. The spring 140 is in a state in which the rotational force that the second shaft member 130 rotates is stored, and the tensioner 1 C is attached to the engine body 300 in this state. And the 2nd shaft member 130 rotates with the rotational force of the spring 140, maintaining the screwing state with the 1st shaft member 120, and advances to an axial direction, rotating.

The stopper member 150 temporarily locks the rotation of the second shaft member 130. The temporary lock by the stopper member 150 is performed before the tensioner 1C is attached to the engine main body 300. After the attachment to the engine main body 300, the temporary lock is released by removing the stopper member 150. The stopper member 150 of this embodiment is formed by bending a thin plate material into a rectangular clip shape as shown in FIG.

As shown in FIG. 41, a part of the side surface portion of the stopper member 150 is opened, and the stopper member 150 is inserted into the second shaft by sandwiching the stopper receiving portion 131 of the second shaft member 130 by the opened opening 151. Engage with member 130. As shown in FIG. 33, this engagement is performed when the stopper receiving portion 131 of the second shaft member 130 is extracted from the extraction hole portion 114 of the support member 110. The second shaft member 130 is locked from the outside of the support member 110. As a result, the axial movement of the second shaft member 130 is temporarily locked. Since the movement of the second shaft member 130 is locked, the rotation of the second shaft member 130 is also locked by the rotational force of the spring 140. The tensioner 1C is attached and fixed to the engine body 300 in such a temporarily locked state.
Disengagement by the stopper member 150 is performed by removing the stopper member 150 from the second shaft member 130 with the tensioner 1 C attached to the engine body 300. The temporary lock by the stopper member 150 is released by removing the stopper member 150. As a result, the second shaft member 130 advances in the axial direction while rotating by the rotational force of the spring 140 while being screwed into the first shaft member 120, and presses the chain guide 340 (see FIG. 34).

The cap 160 is attached to the cap attachment part 133 at the tip portion of the second shaft member 130 as shown in FIGS. As shown in FIG. 40, the cap 160 is formed by a circular contact surface portion 161 and a leg portion 162 extending to the rear side (left side) of the contact surface portion 161.

The leg portion 162 of the cap 160 has a tubular piece shape, and the cap 160 covers the cap attachment portion 133 by extrapolating the tubular piece-like leg portion 162 to the cap attachment portion 133 of the second shaft member 130. It is put on. And after covering the cap attaching part 133, the diameter of the rear end opening part of the leg part 162 is reduced. Thus, the cap 160 is attached to the second shaft member 130 in a state where the cap 160 is prevented from coming off from the cap attaching portion 133 of the second shaft member 130 and is rotatable. The cap 160 may be attached to the second shaft member 130 so as not to rotate.
The contact surface portion 161 of the cap 160 faces the chain guide 340, and when the second shaft member 130 advances in the axial direction, the contact surface portion 161 contacts the receiving surface 344 of the chain guide 340 (see FIG. 34). In this contact state, the second shaft member 130 presses the chain guide 340 (timing chain 330).

Also in the tensioner 1 C of this embodiment, the second shaft member 130 screwed into the first shaft member 120 advances in the axial direction while rotating by the rotational force from the spring 140, and the counterpart member is interposed via the rotatable cap 160. Since the chain guide 340 is pressed to apply tension to the timing chain 330, the tension of the timing chain 330 can be kept constant.
In the tensioner 1 C having this structure, the first shaft member 120 is directly fixed to the support member 110 in a non-rotating state, and the spring force of the spring 140 is engaged with the second shaft member 130 screwed to the first shaft member 120. The cap 160 attached to the second shaft member 130 presses the mating member. In such a structure, since the 1st shaft member 120 does not rotate, the shaft receiver for supporting rotation of the 1st shaft member 120 becomes unnecessary. Further, since the second shaft member 130 advances while rotating, it is not necessary to restrict the rotation, and a bearing for restricting the rotation of the second shaft member 130 becomes unnecessary. Thus, since the shaft receiver and the bearing are not necessary, a case for attaching them is not necessary, and a caseless tensioner can be obtained. Therefore, the number of parts is greatly reduced, the structure is simple, the assembly is easy, and the weight can be reduced.

FIG. 35 shows a state in which the contact surface portion 161 of the cap 160 is in contact with the chain guide 340 (cap receiving surface 344 of the chain guide 340) as the second shaft member 130 advances.
In this embodiment, the contact average diameter φD is determined by the cap sliding surface 137 of the second shaft member 130 with respect to the cap 160 and the shaft sliding surface 163 of the cap 160 with respect to the second shaft member 130. Further, the contact area is determined by the contact surface portion 161 where the cap 160 contacts the cap receiving surface 344 of the chain guide 340 and the cap receiving surface 344 of the chain guide 340 which contacts the contact surface portion 161. Therefore, also in this embodiment, the advance dimension (protrusion allowance dimension) of the second shaft member 130 can be set by adjusting the contact average diameter φD. Further, the contact pressure applied to the cap receiving surface 344 of the chain guide 340 can be adjusted by adjusting the contact area. By increasing the contact area, the surface pressure of the cap receiving surface 344 of the chain guide 340 can be reduced.

[Fifth Embodiment]
42 to 51 show a tensioner 1D according to the fifth embodiment of the present invention. 42 to 45 show the entire tensioner 1D, and FIGS. 46 to 51 show respective components of the tensioner 1D.
The tensioner 1D according to this embodiment includes a first shaft member 520 fixed to the support member in a non-rotating state, and is attached to the first shaft member 520 in a screwed state. A second shaft member 530 that indirectly presses and a spring 540 that applies a rotational force to the second shaft member 530, and the second shaft member 530 advances while rotating by the rotational force applied by the spring 540. A connector member 570 that is configured to press a mating member and that is rotatable in a state in which axial movement is constrained is disposed in a state where the spring 540 and the second shaft member 530 are engaged, and the second shaft member 530 is A structure in which the rotational force of the spring 540 is applied via the connector member 570 advances in the axial direction.
As shown in FIGS. 42 to 45, the above tensioner 1D includes a support member 510, a first shaft member 520, a second shaft member 530, a spring 540, a stopper member 550, a cap 560, and a connector member 570. And.

The support member 510 serves as an attachment member for attaching the tensioner 1D to the engine body 300 (see FIG. 52), and supports the first shaft member 510 in a non-rotating state. As shown in FIGS. 42 to 45 and 46, the support member 510 has a cloud-shaped flat plate-like flange portion 511 and a fixing portion 512 formed on the flange portion 511. The flange portion 511 is a portion that is fixed to the engine main body 300 with a bolt or the like, and mounting hole portions 513 through which the bolt passes are formed on both sides of the fixing portion 512. 44 and 46, reference numeral 514 denotes a stopper hole portion into which a pin-like portion 551 of a stopper member 550 described later is inserted. The pin-like portion 551 of the stopper member inserted into the stopper hole 514 is locked to the connector member 570 (see FIGS. 42 and 43), and the rotation of the connector member 570 is temporarily locked by this locking.

The fixing portion 512 is a portion that fixes the first shaft member 520 in a rising shape. The fixing portion 512 is formed to be recessed in a cylindrical shape at the central portion of the flange portion 511, and the first shaft member 520 is inserted and fixed to the fixing portion 512. The first shaft member 520 is fixed by press-fitting the fixed shaft portion 521 at the rear end portion (the left end portion in FIGS. 43 and 45) into the fixed portion 512 of the support member 510. In this case, in addition to press-fitting, the fixing portion 512 may be crimped so as to reduce the diameter, whereby the first shaft member 520 can be more reliably fixed. The first shaft member 520 can be fixed by means such as screwing, welding, screwing, or the like.

As shown in FIGS. 43, 45 and 47, the first shaft member 520 has a solid shaft shape in which a fixed shaft portion 521 and a shaft portion 522 are integrally formed in the axial direction.
The fixed shaft portion 521 is press-fitted into the fixed portion 512 of the support member 510 at the rear end portion (left end portion). As a result, the first shaft member 520 is supported on the support member 510 in a rising state in a non-rotating state. A slit 524 is formed in the fixed shaft portion 521 along the axial direction so that one end 542 of a spring 540 described later is inserted and locked.

The shaft portion 522 of the first shaft member 520 is connected to the fixed shaft portion 521 in a state where the diameter is larger than that of the fixed shaft portion 521. A male screw portion 523 is formed over the entire length on the outer peripheral surface of the shaft portion 522. Further, when the shaft portion 522 has a larger diameter than the fixed shaft portion 521, an engaging step portion 525 is formed at the boundary portion between them. The engagement step portion 525 acts so as to restrain the later-described connector member 570 from moving in the axial direction.

The second shaft member 530 advances in the axial direction to press the chain guide 340 (timing chain 330) as a counterpart member. As shown in FIGS. 43, 45 and 48, the second shaft member 530 is entirely formed in a cylindrical shape, and the shaft portion 522 of the first shaft member 520 is inserted therein. Therefore, the second shaft member 530 includes a cylindrical tube main body portion 531 extending in the axial direction, and the first shaft member 520 is inserted into the tube main body portion 531.

Such a second shaft member 530 is extrapolated to the first shaft member 520, and advances in the axial direction while rotating in this extrapolated state. An internal thread portion 532 is formed on the inner surface of the tube main body portion 531 of the second shaft member 530. The female screw portion 532 is a portion into which the male screw portion 523 of the first shaft member 520 inserted into the cylinder main body portion 531 is screwed, and the second shaft member 530 advances while rotating by this screwing. In this embodiment, the second shaft member 530 advances while rotating together with the connector member 570, as will be described later. In this embodiment, the female screw portion 532 is formed at a predetermined length at the rear end portion (left end portion) in the cylinder main body portion 531.

A cap 560 described later is rotatably attached to the tip of the second shaft member 530 as shown in FIGS. In order to attach the cap 560, a cap locking groove 533 including a circumferential groove is formed on the outer surface of the cylinder main body portion 531 of the second shaft member 530.

As shown in FIGS. 42, 44, and 48, a sliding surface portion 534 is formed on the tube main body portion 531 of the second shaft member 530. The sliding surface portion 534 is formed by performing a parallel cut (so-called D cut) on both sides of the cylindrical body portion 531 having a circular shape. The sliding surface portion 534 is formed to have a predetermined length along the axial direction with respect to the tube main body portion 531. The sliding surface portion 534 constitutes a rotational force transmitting means 590 together with a facing claw portion 576 of the connector member 570 described later. The torque transmission means 590 will be described later.
Note that a detent protrusion 535 protruding outward in the radial direction is formed at the rear end (left end) of the tube main body portion 531 of the second shaft member 530. The detachment protrusion 535 prevents the second shaft member 530 from coming off the connector member 570 when the second shaft member 530 advances in the axial direction.

As the spring 540 for applying a rotational force to the second shaft member 530, a mainspring spring is used. The mainspring spring 540 is a spring formed by winding a thin plate material having spring properties in a spiral shape, and restoring force is accumulated by winding up, and a rotational force is applied to the second shaft member 530 by this restoring force. The mainspring spring has a merit that the spring constant can be made lower than that of the torsion spring and a stable rotational force can be applied.
The mainspring spring 540 has a spiral spring main body 541, one end (inner end) 542 serving as both ends of the spring main body 541, and the other end (outer end) 543. As shown in FIGS. 42 to 45, the mainspring 540 has a spring main body portion 541 that is externally inserted into the fixed shaft portion 521 of the first shaft member 520 and one end portion (inner end portion) 542 that is slipped by the first shaft member 520. The other end portion (outer end portion) 543 is locked to the leg portion 573 of the connector member 570 and assembled.

The stopper member 550 is a member that temporarily locks the rotation of the second shaft member 530. In this embodiment, the connector member 570 is assembled to the second shaft member 530, and the stopper member 550 engages with the connector member 570 to lock the rotation of the second shaft member 530. As shown in FIG. 51, the stopper member 550 is formed in a pin shape and engages with the connector member 570 (the stopper receiving portion 572 of the connector member 570), and the stopper formed integrally with the pin portion 551. And a base portion 552. The stopper base 552 is in contact with the flange portion 511 of the support member 510 and holds the mounting state of the stopper member 550 on the support member 510.
The stopper member 550 temporarily locks the rotation of the second shaft member 530 via the connector member 570. Temporary locking by the stopper member 550 is performed before the tensioner 1D is attached to the engine body 300, and after the attachment to the engine body 300, the stopper member 550 is pulled out from the support member 510. Thereby, the temporary lock by the stopper member 550 is released.

The cap 560 is attached to the front end surface of the second shaft member 530 as shown in FIGS. As shown in FIG. 50, the cap 560 is formed by a circular contact surface portion 561 and a leg portion 562 extending to the rear side (left side) of the contact surface portion 561.

The leg portion 562 of the cap 560 has a cylindrical shape, and the cap 560 covers the distal end portion of the second shaft member 530 by extrapolating the leg portion 562 to the distal end portion (right end portion) of the second shaft member 530. To be covered. Thereafter, the diameter of the rear end opening of the leg 562 is reduced. Accordingly, the cap 560 is attached to the distal end portion of the second shaft member 530 in a state in which the cap 560 is prevented from being detached from the distal end portion of the second shaft member 530 and is rotatable. The cap 560 may be attached to the second shaft member 530 so as not to rotate.
The contact surface portion 561 of the cap 560 faces the chain guide 340. When the second shaft member 530 advances in the axial direction, the contact surface portion 561 contacts the receiving surface 344 of the chain guide 340 (see FIG. 34). In this contact state, the second shaft member 530 presses the chain guide 340 (timing chain 330). In FIG. 50, reference numeral 563 denotes a shaft sliding surface on which the tip surface of the second shaft member 530 comes into contact with the sliding.

The connector member 570 is disposed so as to engage with the mainspring spring 540 and the second shaft member 530 in a state in which the axial movement is restricted. Such a connector member 570 acts to relay the rotational force of the mainspring spring 540 and transmit it to the second shaft member 530.

FIG. 49 shows the connector member 570. The connector member 570 has a stopper receiving portion 572, a leg portion 573, and a facing claw portion 576. The connector member 570 includes a connector plate portion 571 formed in a bowl shape when viewed from the side. The connector plate portion 571 is formed with a shaft hole portion 574 through which the fixed shaft portion 521 of the first shaft member 520 is inserted. The connector plate portion 571 is set on the engagement step portion 525 of the first shaft member 520 with the first shaft member 520 inserted. As a result, the connector member 570 is assembled in a state where movement in the axial direction is restricted.

The stopper receiving portion 572 is formed by denting two portions at both end portions in the width direction of the connector plate portion 571. A pin-like portion 551 of the stopper member 550 is locked to the stopper receiving portion 572.
The leg portions 573 are formed at a plurality of locations (four locations) around the connector plate portion 571. The leg portion 573 is formed by partially bending the connector plate portion 571 toward the rear side (left side), and the outer end portion of the mainspring spring 540 is formed on any one of the plurality of leg portions 573. 543 is locked (see FIGS. 42 and 43). As a result, the rotational force of the mainspring spring 540 is transmitted to the connector member 570, so that the connector member 570 rotates.

The connector plate portion 571 is formed with a pair of extended plate portions 575 extending to the front side (right side) of the plate portion 571 in a state of being opposed to each other. The pair of extended plate portions 575 are bent so as to approach each other at the extended end portion, and the facing claw portion 576 is formed integrally with the extended end portion. Thus, the facing claw portions 576 are formed in the connector member 570 as a pair.

The pair of facing claw portions 576 are provided so as to face the sliding surface portion 534 formed on the second shaft member 530 and engage with the sliding surface portion 534 in this facing state. Each facing claw portion 576 is formed by a sliding receiving surface portion 577 and an engaging claw portion 578 on both sides of the sliding receiving surface portion 577. The sliding receiving surface portion 577 is formed in a flat shape, and the sliding surface portion 534 of the second shaft member 530 comes into contact, and the sliding surface portion 534 slides in this contact state. The engaging claw portions 578 are engaged with both sides of the sliding receiving surface portion 577 so as to sandwich the sliding surface portion 534 of the second shaft member 530, and the engaging claw portion 578 causes the facing claw portion 576 to become the second shaft member 530. The sliding surface portion 534 is prevented from coming off, and the engagement state between the facing claw portion 576 and the sliding surface portion 534 of the second shaft member 530 can be maintained. Due to such engagement, the rotation of the connector member 570 is transmitted to the second shaft member 530, and the second shaft member 530 rotates together with the connector member 570. At this time, since the second shaft member 530 is screwed with the first shaft member 520, the second shaft member 530 advances in the axial direction and presses the mating member by rotating together. The facing claw portion 576 of the connector member 570 and the sliding surface portion 534 of the second shaft member 530 form a rotational force transmission means 590 that transmits the rotational force of the mainspring spring 540 to the second shaft member 530.

Next, the operation of the tensioner 1D of this embodiment will be described. 42 and 43 show a state in which the advancement of the second shaft member 530 is temporarily locked. By inserting the stopper member 550 into the support member 510, the pin-shaped portion 551 of the stopper member 550 receives the stopper receiver of the connector member 570. Locked to the portion 572. In this state, even if the rotational force of the mainspring spring 540 acts on the connector member 570, the connector member 570 does not rotate and the advance of the second shaft member 530 is locked.

44 and 45 show a state in which the stopper member 550 is pulled out from the support member 510, and the pin-like portion 551 of the stopper member 550 comes out of engagement with the stopper receiving portion 572 of the connector member 570. In this state, the connector member 570 is rotated by the rotational force of the mainspring spring 540. At this time, since the facing claw portion 576 of the connector member 570 is engaged with the sliding surface portion 534 of the second shaft member 530, the second shaft member 530 rotates together with the connector member 570. Since the second shaft member 530 is screwed with the first shaft member 520, the second shaft member 530 advances in the axial direction with rotation. As a result, the cap 560 attached to the distal end surface of the second shaft member 530 comes into contact with the chain guide 340 as the counterpart member, and the second shaft member 530 presses the chain guide 340. On the other hand, if there is a reaction force exceeding the set value from the counterpart member, the second shaft member 530 moves backward in the axial direction while rotating in the reverse direction. Note that the second shaft member 530 does not retract with a reaction force less than the setting.

In such a tensioner 1D, the second shaft member 530 screwed to the first shaft member 520 rotates together with the connector member 570 by the rotational force from the mainspring spring 540, so that it can advance and rotate in the axial direction while rotating. The tension of the timing chain 330 can be kept constant because the chain guide 340 as a counterpart member is pressed through the cap 560 to apply tension to the timing chain 330.
In this tensioner 1D, the first shaft member 520 is directly fixed to the support member 510 in a non-rotating state, and the second shaft member 530 is screwed into the first shaft member 520 and the mainspring via the connector member 570. It advances while rotating by the spring force of the spring 540, and the cap 560 attached to the second shaft member 530 presses the mating member by this advancement. In such a structure, since the 1st shaft member 520 does not rotate, the shaft receiver for supporting rotation of the 1st shaft member 520 becomes unnecessary. Further, since the second shaft member 530 advances while rotating, it is not necessary to restrict the rotation, and a bearing for restricting the rotation of the second shaft member 530 becomes unnecessary. Thus, since the shaft receiver and the bearing are not necessary, a case for attaching them is not necessary, and a caseless tensioner can be obtained. Therefore, the number of parts is greatly reduced, the structure is simple, the assembly is easy, and the weight can be reduced.

In this embodiment, one end 542 of the mainspring spring 540 is locked to the slit groove 524 of the first shaft member 520, but the one end 542 only needs to be locked to the fixed side. You may latch to 510.
In addition, the stopper member 550 is attached to the support member 510, but the present invention is not limited thereto, and the stopper member 550 may be attached to the first shaft member 520 on the fixed side.
Further, the connector plate portion 571 is engaged with the engagement step portion 525 of the first shaft member 520 to restrict the movement of the connector member 570 in the axial direction. A slit may be formed, and the connector member 570 (connector plate portion 571) may be locked in the slit. Further, the cap 560 that is rotatably attached to the tip of the second shaft member 530 may be omitted.

1, 1A, 1B, 1C,

1D Tensioner

2, 110, 510

Support member

3, 120, 520

First shaft member

4, 130, 530

Second shaft member

5, 140, 540

Spring

6, 150, 550

Stopper member

7, 160, 560 Cap 8 Coupling 300 Engine body 340 Chain guide 534 Sliding surface portion 570 Connector member 576 Face claw portion 590 Rotational force transmitting means

Claims

A first shaft member fixed to the support member in a non-rotating state;
A second shaft member that is attached to the first shaft member in a screwed state, and that directly or indirectly presses the mating member by advancing in the axial direction;
A spring for directly applying a rotational force to the second shaft member,
The tensioner, wherein the second shaft member advances while rotating by a rotational force applied by the spring and presses the mating member.
The tensioner according to claim 1, wherein the advancement of the second shaft member is supported only in a state where the second shaft member is screwed to the first shaft member.
A cap that is directly or indirectly in contact with the tip surface of the second shaft member and is rotatable with respect to the second shaft member; and the cap is in contact with the mating member. The tensioner according to claim 1 or 2.
The contact average diameter at which the second shaft member and the mating member or the second shaft member and the cap are in contact with each other is set in accordance with the advancing dimension of the second shaft member. The tensioner of any one of Claims.
The tensioner according to claim 1, wherein the spring is a torsion spring having one end locked to the first shaft member and the other end locked to the second shaft member.
2. The tensioner according to claim 1, wherein the spring is a mainspring spring having one end locked to the first shaft member and the other end locked to the second shaft member.
A stopper whose rear end engages with the support member or the first shaft member and is rotationally restrained, and whose front end engages directly or indirectly with the second shaft member to lock the rotation of the second shaft member. The tensioner according to claim 1, wherein the member is inserted so as to be detachable in an axial direction of the second shaft member.
A stopper member that detachably engages with the second shaft member and locks the movement of the second shaft member in the axial direction is detachable from the support member or the first shaft member. The tensioner according to claim 1.
A first shaft member fixed to the support member in a non-rotating state;
A second shaft member that is attached to the first shaft member in a screwed state, and that directly or indirectly presses the mating member by advancing in the axial direction;
A spring for applying a rotational force to the second shaft member,
The second shaft member is structured to advance while rotating by the rotational force applied by the spring and press the mating member,
A connector member that is rotatable in a state in which axial movement is constrained is disposed in a state of being engaged with the spring and the second shaft member, and the second shaft member receives a rotational force of the spring via the connector member. A tensioner that advances in the axial direction when applied.
10. The tensioner according to claim 9, wherein the spring is a mainspring spring having one end locked to the first shaft member or the support member and the other end locked to the connector member.
10. The tensioner according to claim 9, wherein a stopper member that engages with the connector member to lock the rotation of the connector member is detachable from the support member or the first shaft member.
10. The tensioner according to claim 9, wherein a cap capable of rotating with respect to the second shaft member is attached in contact with a tip surface of the second shaft member.
10. The tensioner according to claim 9, wherein the connector member and the second shaft member are formed with a rotational force transmitting means for transmitting the rotational force by engaging with each other.
14. The tensioner according to claim 13, wherein the second shaft member advances in the axial direction with the rotational force transmitting means engaged with each other.
The rotational force transmitting means is engaged with a sliding surface portion formed along the axial direction of the second shaft member so as to face the sliding surface portion, and the sliding surface portion slides in the engaged state. The tensioner according to claim 14, wherein the tensioner is formed by a facing claw portion formed on the connector member.