JPS5914652B2 - Tensiona - Google Patents

Description

[Detailed Description of the Invention] The present invention is equipped with a sliding device having a pair of parallel leaf springs, and enables stable chain transmission by running a tensioner along the entire length of the chain's fleece pants. Related to Uru tensioner.

For example, in a chain device that rotates at high speed, such as the camshaft drive of the engine of a car or motorcycle, the tensioner installed on the slack side has the basic function of applying tension to the chain and suppressing vibration. , a chain that reliably prevents the chain from riding on the teeth, jumping over it, incorrectly meshing, biting, etc. even when the chain is stretched to a certain extent and shocks are applied to the chain, such as during high-speed rotation or when starting up. It is desired that

As a result of numerous experiments conducted on the performance of such tensioners, the present invention proposes that the tensioner be disposed over the entire length of the free span between the chain wheels, and that the chain wheel and chain be separated as the chain stretches. The present invention has been completed by discovering that it is preferable to displace both ends of the tensioner to follow the movement of the engagement/disengagement point of the tensioner in order to exhibit the above-mentioned performance. The purpose of the present invention is to provide a tensioner that is equipped with a sliding tool and can efficiently reduce chain vibration, riding up, improper meshing, etc., and one embodiment thereof will be described below with reference to the drawings.

Fig. 1 shows an embodiment in which the device of the present invention is adopted in a camshaft drive device of an engine using a silent chain. The tensioner 1 of the present invention is disposed on the slack side 5 of the silent chain 4 wound around the belt.

The large chain wheel 3 and the small chain wheel 2 have a tooth ratio of 2:l, and a straight chain guide 6 is attached to the tension side t of the chain 4.

The tensioner 1 of the present invention has a support 7 and a sliding tool 5 attached to the support I, and the sliding tool 5 is formed to be longer than the length of the chain 4 between the chain wheels 2 and 3. An elastic piece 11,1 made of a relatively soft elastic material such as rubber, including both ends of the flat spring 10.
The leaf springs 10.10 are held in parallel by interposing the springs 2.13 and bonding them together by baking, gluing, etc.

Further, support pins 15 are implanted in the elastic support pieces 11 at both end portions aha with their both ends protruding.

Further, a chain sliding piece 17 made of rubber is attached to the lower leaf spring 10 over substantially its entire length.

In addition, a spring receiver 19 is attached to the leaf spring 10 located at the upper side in the figure.
．． 19 are protruded from both ends, and a guide bin 2 is provided in the center.
0 is provided with a rising piece 21 attached in a direction transverse to this leaf spring 10.

The support 7 is formed by bending a steel plate into a U-shape, and the protruding pieces 22 on both sides of the end are provided with arc-shaped guide grooves or end cam holes 23.2 that are inclined diagonally inward and into which the support bin 15 is loosely inserted.
4 is drilled, and in the center is a mounting piece 26.2 for mounting.
6 are placed opposite each other by cutting and raising.

Further, the side plate of the central portion of the support 7 extends downward, and a slightly inclined central guide groove portion, or central cam hole 27, into which the guide pin 20 can be inserted is provided in the extended portion.

The end cam holes 23, 24 and the center cam hole 27 correspond to the movement curve of the engagement point C1 and disengagement point d between the chain wheels 2, 3 and the chain 4 as the chain 4 stretches. The curve can be determined.

For example, if the elongation of the chain 4 is absorbed while maintaining the arc running line A as shown in Fig. 3, then the arc running line A and the pitch circle PC of the chain wheels 2 and 3
2. The engagement point C and the disengagement point d, which are the contact points with PC3, are
Pitch circle P from point e1 to point C2 and from point d1 to point d2, respectively.
C2, PCa, and at that time points e and f on the extension line corresponding to the external position of the sliding tool 5 pass on the curves E and F.

Such a curve E. F can be easily obtained by drawing.

Further, a point g corresponding to the position of the central guide bin 20 passes through a curve G that goes downward and slopes toward the small chain wheel 2 side.

Therefore, if the mounting position of the support pin 15.15 of the sliding tool 5 is made to coincide with the point esf, the support pin 15.15 will follow the curve E.

The end cam holes 23 and 24 are displaced along the curves E and F, respectively, and the central cam hole 27 is also formed to match the curve G.

A spring 30, 30 is attached between the spring receiver 19, 19 and the mounting bolt passing through the mounting piece 26 to urge the slider 5 to curve.

The tensioner 1 of the present invention has such a sliding device 5 mounted close to the chain wheel 2.3.

At the time of attachment, the two end portions asa are attached so that the positions close to the chain wheels 2 and 3 are separated from the upper surface of the chain 4 by a slight distance.

However, the tensioner 1 of the present invention is installed using the mounting bolts passing through the mounting pieces 26, so that both ends ah of the tensioner 1 are fixed.
a can be displaced along the movement curve of the engagement point c1 and separation point d between the chain wheel 2.3 and the chain 4 as the chain elongates.

At the center, the springs 30, 30 press the chain 4 with maximum pressing force.

Furthermore, since the sliding tool 5 has a pair of leaf springs 10.10 disposed facing each other and integrally connected via elastic support pieces 11 and 12.13, the leaf springs 10.10 are arranged at equal intervals. It is possible to bend the upper and lower leaf springs IQ and 1Q to have the same radius of curvature while maintaining the same radius of curvature, and the bending resistance increases, allowing the chain to properly form an arc without causing partial point deformation when sliding in contact with the chain 4. I can guide you.

As mentioned above, in the tensioner of the present invention, both ends of the sliding tool, which is made up of two leaf springs integrally joined by an elastic support member, are displaced as the engagement and disengagement points, that is, the engagement and disengagement points, move. It prevents jamming, riding, and jumping between the chain and chain wheel, guides the running links to the chain wheel's meshing bacteria, enables smooth engagement and disengagement, and reduces vibration and noise, reducing the accompanying tension. This can prevent wear and fatigue.

It is also obvious that the guide grooves at the ends and the center can be formed into sliding tools, and the support pins can be formed into supporting tools.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of the present invention, FIG. 2 is a diagram showing an example of its installation, and FIG. 3 is a diagram showing its operation. 1...Tensioner, 2.3...Chain L
4...Chain, 5...Sliding tool,
7... Support tool, 10... Leaf spring, 11
．． 12.13...Elastic support piece, 15...
・Support pin, 20... Spring.

Claims (1)

[Claims] 1. Consists of a sliding tool in which an elastic support piece is interposed between two parallel plate springs to keep the leaf springs at equal intervals, and a supporting tool for attaching the slide and the moving tool, and A spring for curving the sliding tool is attached to the sliding tool, a support pin is protruded from one side of the sliding hole support, and a guide groove for guiding the support pin is formed in the other, A tensioner characterized in that the guide groove has a curved line that guides the support pin to displace both ends of the slider along the engagement/disengagement point between the chain wheel and the chain.