JPS6224857Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a chain tensioner that rotates as the slack of the chain increases and absorbs the slack of the chain, by rolling the tensioner on the concentric circle of the chain wheel. Always guides the chain in the tangential direction of the chain wheel to prevent interference due to excessive engagement at the start and disengagement positions of the chain and chain wheel, maintaining normal engagement and absorbing chain slack. This relates to a tensioner support device that can be used.

Conventionally, chains such as roller chains and silent chains used for power transmission are
As shown in the figure, during high-speed transmission, flapping frequently occurs on the slack side C of the chain, causing interference and other improper engagement between the chain and the chain wheel S, and this improper engagement causes an abnormality in the chain wheel S. Wear/heat generation/
This was causing noise and damage.

Therefore, in order to prevent such chain flapping, chain tensioners T and T' as shown in FIG. 2 or 3 have been installed.

However, in conventional chain tensioners like this, the rotation axis of the tensioner is fixed at one point, so even if the pressing surface of the tensioner is initially installed in the tangential direction of the concentric circle of the chain wheel, it will not move against the chain. As it presses and rotates, it approaches a line that cuts the circle straight, and as a result, the chain is clamped excessively between the chain tensioner and the chain wheel, causing abnormalities in the pressing surface of the chain tensioner, the chain, and the chain wheel teeth. Not only do they cause friction and generate heat, wear, and noise, but they also have the disadvantage of increasing loss of power transmission force and significantly reducing power transmission efficiency.

Therefore, the purpose of the present invention is to eliminate such conventional drawbacks, and to prevent abnormal heat generation, wear, and noise of the chain and chain wheel teeth by regularly meshing the chain and chain wheel, and to improve power transmission efficiency. To provide a support device for a chain tensioner capable of absorbing slack in a chain without reducing the chain tensioner.

The present invention has the following structure to achieve the above object. That is, the present invention moves the center of rotation of the chain tensioner as the chain tensioner presses and rotates, and supports the tensioner so that the pressing surface of the tensioner is always located on the tangent to the concentric circle of the chain wheel. The base of the tensioner is supported in an elongated hole that guides and guides the tensioner pressing surface so that it rolls on the concentric circle of the chain wheel.

Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 4 to 7.

FIG. 4 shows a supporting device for a chain tensioner according to the present invention. First, a pair of pins 2 and 3 are spaced back and forth and protrude from the base of the tensioner that presses the back surface of the slack side C of the chain. The frame 4 supporting the chain is provided with a pair of elongated holes 6 corresponding to the locus of the pair of pins 2 and 3 formed when the pressing surface 5 of the tensioner base against the chain rolls on the concentric circle of the chain wheel S.
A spring 8 is interposed between the free end of the tensioner 1 and the frame to press and bias the tensioner against the chain C on the slack side. be. Note that instead of the above embodiment, it is possible to provide a pin protruding from the frame and to drill a long hole in the base of the tensioner, and instead of a spring, a known pressing means such as a cylinder device may be used. You can also do it.

Therefore, when the tensioner 1 is pressed and rotated as shown in FIG. 6 by the biasing force of the spring 8 as the slack of the chain C increases, the pressing surface 5 of the tensioner base is guided to engage with the pin and the elongated hole. Since the chain wheel is made to roll on the concentric circle of the chain wheel, the chain at the meshing position with the chain wheel is not always subjected to excessive pressing force, and the chain is guided in the tangential direction of the chain wheel and meshes (driven chain (in the case of cars) and disengagement (in the case of drive chain wheels), not only does the slack in the chain be absorbed and flapping is prevented, but also the normal meshing state is maintained, eliminating the drawbacks of the conventional methods mentioned above. efficient conduction.

The tensioner support device shown in FIG. 7 is another embodiment in which pins and elongated holes are arranged above and below the pressing surface of the tensioner base, and the tensioner is rolled in the same way as in the previous embodiment.

Further, it is more effective to attach a sliding member 9 made of plastic or the like to the pressing surface of the tensioner in order to obtain smooth contact with the chain.

[Brief explanation of the drawing]

Fig. 1 is a front view showing the flapping phenomenon that occurs in the chain on the slack side, Figs. 2 and 3 show a conventional chain tensioner support device, and Figs. 4 to 6 show the first embodiment of the present invention. , Figure 4 is a front view, Figure 5 is a front view.
The figure is a sectional view taken along the line A-A in Figure 4, Figure 6 is a front view showing the state when the chain tensioner is pressed and rotated to the maximum extent, and Figure 7 is a cross-sectional view taken along the line A-A in Figure 4. This shows an example. 1... Tensioner, 2, 3... Pin, 4... Frame, 5... Tensioner base pressing surface, 6, 7...
...Elongated hole, 8...Press biasing means, C...Loose side chain, S...Chain wheel.

Claims (1)

[Scope of utility model registration request] A pair of pins are provided protruding from either the base of the chain tensioner, which presses the slack side of the chain suspended between a pair of spaced chain wheels to absorb the slack of the chain, and the frame that supports the base. , a pair of elongated holes corresponding to the locus of the pair of pins drawn when the pressing surface of the base of the tensioner with respect to the chain rolls on the concentric circle of the chain wheel are drilled in one of the other one of the pairs. A chain tensioner support device in which the pair of pins are inserted and supported in each of the elongated holes, and means is interposed between the free end of the tensioner and the frame to press the tensioner against the slack side chain.