JPH0430450Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field]

This invention relates to an auto-tensioner device for a power transmission belt used in an engine, and particularly to a belt auto-tensioner device for adjusting the tension of a toothed timing belt that transmits power from an automobile engine crankshaft.

[Prior art]

For example, in an automobile engine, an autotensioner device as shown in FIG. 5 is known, which prevents slack and adjusts the tension of a toothed timing belt that is stretched between a crankshaft pulley and a camshaft pulley. It is being (Refer to Japanese Utility Model Application Publication No. 62-45451) This consists of an idler pulley 51 that engages with a belt 50 that transmits engine power, an arm 52 that swingably supports this idler pulley 51, and a belt that supports this arm 52. 50, and a common base plate 54 that holds the arm 52 and the tensioner 53. an elongated hole 56 extending approximately in the rotational direction around the center;
57, and this fulcrum hole 55 and elongated holes 56, 5
The base plate 54 is fixed to the engine via the base plate 7. Further, the base plate 54 is provided with a stopper 58 made of an adjustment screw, and when the stopper 58 is tightened, the arm 52 comes into contact with this and pushes the piston rod 59 of the tensioner 53. The stopper 58 is used during assembly. The positions of the arm 52 and piston rod 59 are fixed depending on the tightened position. Stopper 5 on base plate 54
8, before attaching the base plate 54 to the engine body, tighten the stopper 58 to remove the arm 52.
After fixing the piston rod 59 of the tensioner 53 in a predetermined position, applying tension to the belt 50, and fixing the base plate 54, the stopper 58 is removed. When tension is applied to the belt 50, a load corresponding to the tension is applied to the tensioner 53, and the piston rod 59 retreats against the spring 60.
At this time, due to the damper action of oil moving between the liquid chambers 61 and 62, the retraction of the piston rod 59 is delayed. For this reason, if the piston rod 59 is fixed in advance at a predetermined position by the stopper 58 and the biasing force of the spring 60 is strengthened as described above, the piston rod 59 will not move backward and will not be subjected to damping action. Further, according to this, the base plate 54 can be fixed with a slight tension applied to the belt 50, and when the stopper 58 is removed depending on the amount of tightening of the stopper 58, a predetermined belt tension is applied. Therefore, the belt tension can be set more easily and quickly.

[Problem that the invention attempts to solve]

However, in this type of conventional device, in order to move the piston rod 59 of the tensioner 53 backward, the entire device including the base plate 54 must be removed, the arm 52 and the rear part of the tensioner 53 must be compressed using a vise, etc., and then fixed with a stopper 58. This had the inherent problem of poor workability and the fact that it was only possible with this type of unit. Further, a lug is required to attach the stopper 58 to the base plate 54, and once the stopper 58 is attached, it becomes unnecessary, and the stopper 58 is required again when replacing the belt or the tensioner.

[Means to solve the problem]

In order to solve the above problems, this invention includes an inner member and an outer member rotatably fitted on the inner member,
an idler pulley that engages with a belt that transmits engine power to apply tension to the belt; an arm to which the idler pulley is attached and which has a fulcrum hole at one end serving as a center of swing; A belt auto-tensioner device consisting of an auto-tensioner that presses toward the tension side, where a fulcrum pin is inserted into the fulcrum hole to make the arm swingable, and the swinging angle is set by abutting against the arm. A washer integrally having a tongue-shaped stopper was attached between the fulcrum pin and the fixing bolt.

[Effect]

Attach a washer with a stopper to the bolt, bring the rod of the autotensioner into contact with the arm at the pre-pushed position, and tighten and fix the bolt to set the rod in a predetermined position. After attaching the autotensioner device in this state to the engine and applying a predetermined tension to the belt, loosen the bolt, rotate the washer with the stopper approximately half a turn, and then tighten the bolt again. In this way, the operation of the arm will not be hindered.

【Example】

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings shown in FIGS. 1 to 4. FIG. 1 is a front view showing an embodiment of the present invention, and FIG. 2 is a side sectional view. An idler pulley 2 that performs initial adjustment of the tension of the timing belt 1 is fixed to a substantially L-shaped arm 3. The arm 3 is swingably attached to a bracket 5 via a fulcrum pin 4 inserted into one end thereof, and the other end is arranged to abut against a rod 7 of an autotensioner 6 fixed to the bracket 5. The bracket 5, which holds the arm 3 and autotensioner 6 together, is fixed to the engine body 8 with bolts 9. The idler pulley 2 consists of a shaft-shaped inner member 10 and an outer tube 12 rotatably attached to the inner member 10 via a ball bearing 11. Inner member 10
An eccentric hole 13 is provided on one side, and a pretension hole 14 is provided on the opposite side to engage a pretension jig (not shown).
is provided. Numeral 15 is a bolt for fixing the idler pulley 2 to the arm 3, and serves as a fulcrum when the idler pulley 2 is swung by a pretension jig.
The arm 3 is approximately L-shaped, and has a bent portion 16 for mounting the idler pulley 2, and a support portion 1 having a fulcrum hole 17.
8, and an operating part 1 that comes into contact with the rod 7 of the autotensioner 6 and swings according to the advance and retreat of the rod 7.
It consists of 9. Between the fulcrum hole 17 and the fulcrum pin 4, a synthetic resin bush or oil-impregnated bearing 20, which is highly wear resistant and has good sliding characteristics, is inserted to smooth the swinging motion of the arm 3. Note that the outer surface of the fulcrum pin 4 or the inner surface of the fulcrum hole 17 may be directly coated with this type of resin. On the other hand, the stroke of the rod 7 of the autotensioner 6 cannot be made too long due to its strength, and is usually limited to around 10 mm. Therefore, in order to make effective use of this short stroke, it is necessary to initially adjust the mounting position of the autotensioner device on the engine body 8. Among the dimensional variations of each part, the variation in the length of the belt 1 is particularly large, and usually has an error of about ±6 mm. For the above-mentioned initial adjustment, when swinging the idler pulley 2, the arm 3 is set at a predetermined angle.
A washer 22 having a stopper 21 for temporarily locking the fulcrum pin 4 is attached to the fulcrum pin 4. Here, the gap L1 between the bracket 5 and the washer 22 and the width L2 of the support part 18 of the arm 3 are set such that L1>L2, and the fixing bolt 2
4, the arm 3 can swing. The washer 22 is, for example, a tongue-shaped stopper 2 bent into a part of a disc as shown in FIG.
1 is formed and abuts against the neck 25 of the arm 3 to maintain the set angle of the arm 3. After applying a predetermined tension to the belt 1, loosen the fixing bolt 24 and rotate the washer 22 approximately half a turn as shown in FIG.
Tighten the fixing bolt 24 again. Therefore, the stopper 21 does not come into contact with the neck 25 of the arm 3, and the operation of the arm 3 is not hindered.
When setting the angle of arm 3, set the washer 22 in advance.
is brought into contact with the neck portion 25 of the arm 3. In this embodiment, the fixing bolt 24 is preferably left-handed threaded for operational reasons.

[Effects] The present invention has the above configuration and has the following unique effects. (a) It can be easily set by simply loosening the fixing bolt, rotating the washer, and tightening the fixing bolt again, greatly improving work efficiency. (b) Washers can be reused, so there is no need to keep stopper parts on hand at a repair shop, for example. (c) It acts as a locking bolt for fixing bolts.
The practical effect is high. (d) There is no need for extra parts or additional work on the bracket, which is advantageous in terms of cost.

[Brief explanation of drawings]

FIG. 1 is a front view showing an embodiment of the belt autotensioner device according to the present invention, FIG. 2 is a cross-sectional side view of the same, and FIG. 3 is a perspective view of a washer with a stopper function applied to the present invention. FIG. 4 is an explanatory view showing the operation, and FIG. 5 is a front view showing a conventional example. 2...Idler pulley, 3...Arm, 4...
Fulcrum pin, 5... Bracket, 6... Auto tensioner, 21... Stopper, 22... Washer,
24...Fixing bolt.

Claims (1)

[Scope of utility model registration request] an inner member; an idler pulley rotatably fitted on the inner member; and an idler pulley that engages with a belt that transmits engine power to apply tension to the belt; A belt auto-tensioner device consisting of an arm having a fulcrum hole serving as a center of movement, and an auto-tensioner that presses the arm toward the tension side of the belt, wherein a fulcrum pin is inserted into the fulcrum hole to tighten the arm. Swingable and free,
A belt auto-tensioner device characterized in that a washer integrally having a tongue-shaped stopper that comes into contact with the arm to set the swing angle is mounted between the fulcrum pin and the fixing bolt.