JPS634836Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a timing belt tension adjustment device in a vehicle or other engine.

(Prior Art) Conventionally, as shown in FIG.
A type of engine is known which includes a vertical timing belt f extending between the timing belt f and the cam pulley e on the upper camshaft d, and an adjuster roller g that presses the slack side of the belt f from the outside. In this case, as shown in the figure, the roller g is pivotally supported on a swingable support lever i that is biased to one side by a spring h, and is positioned and fixed by a bolt j connected thereto. Generally, when adjusting the tension, the roller g is brought into pressure contact with the belt f by the spring h to apply tension to the belt f, while the belt f
The operator presses the tension side part of the tension side from the outside at a point P between them with his/her finger to check the tension.
Next, according to the result of the confirmation, the roller g is manually moved in and out with the lever i to correct the tension, and when the predetermined tension is confirmed, the roller g is positioned and fixed. ing.

(Problems to be Solved by the Invention) The above-mentioned work relies heavily on confirmation with fingers, and the tension thus obtained is inevitably accompanied by some error.

(Means for Solving the Problems) The purpose of the present invention is to provide a device that does not have such inconveniences, that is, a device that can always accurately and reliably obtain a predetermined tension state without the need for finger confirmation. On the side of the engine body, there is a vertical timing belt that extends between the crank pulley on the crankshaft and the cam pulley on the camshaft above it.
A tension adjustment device for a timing belt in an engine equipped with an adjuster roller that presses a slack side portion of the belt from the outside, comprising: a jig main body that can be detachably attached to a side surface of the engine main body; and an outer end of the crankshaft. a removable jig lever that rotationally engages with the jig lever; a first air cylinder that extends between the jig lever and presses and tilts the lever; and a first air cylinder that presses and tilts the lever; It includes a second air cylinder that presses inward, and a pressure roller that presses the tension side portion of the belt from the outside.

(Example) An example of implementing the present invention will be explained with reference to attached drawings. Fig. 2 shows a front view of one example, and 1 indicates the engine body, and on the side of the main body 1 there is a crank pulley 3 on the crankshaft 2 that is driven counterclockwise in the drawing, and the upper side of the engine body. cam pulley 5 on camshaft 4 of
Vertical tensioner belt 6 extending between
and an adjuster roller 7 that presses the slack side portion of the belt 6 from the outside. In the illustrated example, two cam pulleys 5 are provided on the left and right, and a water pump pulley 8 is provided below the cam pulleys 5. Furthermore, the roller 7 is attached to the tip of a support lever 10 that is swingable about a shaft 9 at the root. It is of a type that is pivotally supported by a section and is positioned and fixed by a bolt 11 that is inserted through the section.

Here, the device of the present invention consists of a removable jig main body 1 that extends longitudinally in the lateral direction on the side surface of the engine main body 1.
2, and a removable jig lever 13 rotatably engaged with the outer end of the crankshaft 2,
A first air cylinder 1 extends between the jig main body 12 and the jig lever 13 and presses and tilts the lever 13.
4, a second air cylinder 15 that presses the roller 7 inward from the outside, and a pressing roller 16 that presses the left tension side portion of the belt 6 from the outside at the point P previously described. The jig main body 12 is as shown in FIG. The main body 1 is attached to the main body 1 through a bolt 20 at a mounting arm 19 which is removably fitted into the notch hole 18 and is provided at the other end.
The above-mentioned second air cylinder 15 is installed horizontally on the second air cylinder 15, and the above-mentioned pressure roller 16 is rotatably supported, and the above-mentioned first air cylinder 14 is attached at the base of the second air cylinder 15. It was supported by a shaft and protruded downward.

Furthermore, the jig lever 13 is as clearly shown in FIGS. 5 and 6, and is removably fitted to the outer end of the crankshaft 2 in the shaft hole 21 of the root, and is connected to the key of the crankshaft 2. A key 22 fixed to the shaft hole 21 in the groove
and is rotationally engaged with the seat 23 at the tip thereof.
The tip of the first air cylinder 14 described above is supported from its lower surface.

Furthermore, as shown in FIG. 7, both of the cylinders 14 and 15 described above are provided so as to be connectable to an external pressure air source 26 via a switching valve 25 that responds to a switch lever 24. A speed control circuit 27 is inserted in the side flow path to delay its operation to some extent.

Furthermore, in preparation for the work described later, the lock pin 2 is attached to the camshaft 4 via the upper cap 28.
9 is provided so as to be freely inserted and removed, so that the cam pulley 5 on the shaft 4 can be temporarily fixed.

(Function) In order to adjust the elasticity using the proposed device, first,
After attaching the jig main body 12 and the jig lever 13, and then fixing the cam pulley 5 by applying the lock pin 29 described above, switch the switching valve 25 using the switch lever 24 to connect the first air cylinder 14 and then the second air cylinder 15. and are activated in sequence.

According to the operation of the first cylinder 14, the crank pulley 3 is rotated counterclockwise in the drawing via the jig lever 13 and the crankshaft 2, and the belt 6 is rotated counterclockwise in the drawing.
The part between the tension sides, i.e. the left half in the drawing, is driven so that a predetermined tension state is obtained, more or less pressed inward by the pressure roller 16 at the point P, and then by the actuation of the second cylinder 15. According to this, the other half of the belt 6 loosens due to the above-mentioned driving,
That is, as the right half in the drawing is pushed by the adjuster roller 7 as it moves forward, the slack is removed, so the bolt 1 that inserts the roller 7 there.
1 to fix it in that position and finish the setting work.
Next, each cylinder 14, 15 is returned to its inoperative state, and the jig main body 12 and jig lever 13 are removed, and thus the belt 6 is brought to a predetermined tension state in which the pressure at point P is released.

(Effect of the invention) As described above, according to the invention, the timing belt is first driven by the first air cylinder at its tension side portion, and the scheduled part is pushed slightly inward by the pressing roller at the intermediate scheduled point. The device is set in a tensioned state, and then the second air cylinder presses the adjuster roller on the slack side of the roller to remove the slack in that portion. This has the effect of making it possible to smoothly and reliably adjust the tension while eliminating the inconvenience of the above.

[Brief explanation of drawings]

FIG. 1 is a front view of a conventional example, FIG. 2 is a front view of an example of the proposed device, and FIG. 3 is a cross-sectional view taken along the - line.
4 is a side view of the jig main body, FIG. 5 is a side view of the jig lever, FIG. 6 is a plan view thereof, and FIG. 7 is an air circuit diagram thereof. 1...Engine body, 2...Crankshaft, 3...
... Crank pulley, 4 ... Camshaft, 5 ... Cam pulley, 6 ... Timing belt, 7 ... Adjustment roller, 12 ... Jig body, 13 ... Jig lever, 14, 15 ... 1st 2nd Air cylinder, 16
...Press roller.

Claims (1)

[Scope of utility model registration request] On the side of the engine body, there is a vertical timing belt that extends between the crank pulley on the crankshaft and the cam pulley on the camshaft above it, and an adjustment roller that presses the slack side of the belt from the outside. A timing belt tension adjustment device for a timing belt engine includes a jig main body that is detachably attached to a side surface of the engine main body, and a jig lever that is detachable and that is rotatably engaged with the outer end of the crankshaft. a first air cylinder extending between the jig body and the jig lever to press and tilt the lever, a second air cylinder to press the adjusting roller inward, and a second air cylinder on the tension side of the belt. A timing belt tension adjustment device comprising a pressure roller that presses a portion from the outside.