Device for removing slack and vibration in the chain of a chain drive

Abstract

The present disclosure discloses an apparatus (100) for removing slack and vibration in a chain (400) that includes a piston-cylinder device. A first piston (10) is configured to be displaced within a cylinder (20) of the piston-cylinder device, and a second piston (30) is configured to be displaced within a cavity (40) defined inside the first piston (10) with the axis of the cavity (40) coaxial with the axis (A) of the cylinder. A lubricating oil passage (50) is defined to pass through the first piston (10), the second piston (30), and the cylinder (20) of the piston-cylinder device. The apparatus facilitates vibration reduction, slack removal, and automatic lubrication of the chain drive.

Description

Technical Field

[0001] The present disclosure relates to the field of chain drives, and more particularly to a slack and vibration removal device used with a chain drive.

Background Art

[0002] The following background information is relevant to the present disclosure but is not necessarily prior art.

[0003] Chain tensioner devices facilitate the removal of chain slack that occurs in chain drives. Chain slack is a result of the long-term use of the chain drive. The links of the chain drive increase in length depending on the usage time of the chain drive. Chain drive slack causes undesirable vibrations and thus results in a noisy operation of the chain drive. Conventional devices for removing chain slack and vibration typically have a pre-tensioned spring that facilitates the removal of slack and prevents a noisy and vibrating operation. However, in order to eliminate such slack, the stiffness of the spring needs to be adjusted each time. This requires regular service procedures. Additionally, the chain drive needs to be lubricated frequently, which also requires regular maintenance scheduling. Further, adjusting the slack of the chain drive requires human skill as the spring characteristics vary for specific applications.

[0004] Therefore, there is a felt need for a device for removing chain drive slack and vibration that overcomes the aforementioned problems.

Summary of the Invention

Problems to be Solved by the Invention

[0005] Some of the objectives of the present disclosure that are met by at least one embodiment herein are as follows.

[0006] The object of the present disclosure is to provide an apparatus for removing slack and vibration of a chain drive that eliminates the need for periodic maintenance and service.

[0007] Another object of the present disclosure is to provide an apparatus for removing slack and vibration of a chain drive that eliminates the need for skilled labor.

[0008] Yet another object of the present disclosure is to provide an apparatus for removing slack and vibration in a chain drive that provides optimal chain drive performance.

[0009] Other objects and advantages of the present disclosure will become more apparent from the following description, which is not intended to limit the scope of the present disclosure.

Means for Solving the Problems

[0010] The present disclosure discloses an apparatus for removing slack and vibration of a chain provided with a piston-cylinder device. A first piston is configured to be displaced inside a cylinder of the piston-cylinder device, and a second piston is configured to be displaced inside a cavity defined inside the first piston with the axis of the cavity being coaxial with the axis of the cylinder. A lubricating oil passage is defined to pass through the first piston, the second piston, and the cylinder of the piston-cylinder device. The present apparatus facilitates reduction of vibration, removal of slack, and automatic lubrication of the chain drive.

[0011] A first end 50a of the lubricating oil passage is configured to be in fluid communication with the chain drive, and a second end 50b of the lubricating oil passage is configured to be in fluid communication with a lubricating oil reservoir.

[0012] In a preferred embodiment, a grease port is provided at one end of the cylinder, and the grease port is configured to be in fluid communication with the first piston.

[0013] The device is equipped with a pressure sensor on the cylinder to detect the pressure of the grease inside the cylinder.

[0014] The device is equipped with a throttle valve attached to one end of the lubricating oil passage.

[0015] The first piston is configured to be displaced by the pressure of the grease flowing through the grease port.

[0016] The second piston is configured to be displaced by the pressure of the silicone oil housed inside the cavity.

[0017] The sprocket wheel is configured to be attached to the second piston at one end and to come into contact with the chain drive at the other end.

Brief Description of the Drawings

[0018] Here, an apparatus for removing slack and vibration of a chain drive according to the present disclosure will be described with reference to the accompanying drawings.

[0019]

Figure 1

Figure 2

Figure 3

Figure 4

Explanation of Reference Numerals

[0020] 1000 Chain drive A Longitudinal axis 10 First piston 20 Cylinder 30 Second piston 40 Cavity 50 Lubricating oil passage 50a First end of the lubricating oil passage 50b Second end of the lubricating oil passage 52 Throttle valve 60 Lubricating oil reservoir 70 Grease port 72 Pressure sensor 74 Grease dispenser 76 Pump 80’,80 Sprocket wheel 100,100’ Device 100a First end 100b Second end 200,200’ Driving sprocket 300,300’ Driven sprocket 400,400’ Chain

Best Mode for Carrying Out the Invention

[0021] Here, embodiments of the present disclosure will be described with reference to the drawings.

[0022] The embodiments are provided to fully and completely convey the scope of the present disclosure to those skilled in the art. To provide a complete understanding of the embodiments of the present disclosure, numerous details regarding specific components and methods are described. It will be apparent to those skilled in the art that the details provided in the embodiments should not be construed as limiting the scope of the present disclosure. In some embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

[0023] The terms used in this disclosure are for the purpose of describing particular embodiments only and such terms should not be regarded as limiting the scope of the disclosure. As used in this disclosure, the forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having” are open-ended transitional phrases and thus specify the presence of the stated features, elements, modules, units, and / or components, but do not preclude the presence or addition of one or more other features, elements, components, and / or groups thereof. The particular order of the steps disclosed in the methods and processes of this disclosure should not necessarily be construed as requiring the performance as described or illustrated. It should also be understood that additional or alternative steps may be used.

[0024] When an element is referred to as being “attached to,” “engaged with,” “connected to,” or “coupled to” another element, it may be directly on, engaged with, connected to, or coupled to the other element. As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed elements.

[0025] The terms such as “inner,” “outer,” “directly below,” “below,” “lower,” “above,” “upper,” etc. can be used in this disclosure to explain the relationships between different elements as depicted from the figures.

[0026] FIG. 1 shows a chain drive 1000' according to the prior art, having an apparatus 100' with a sprocket wheel 80' for removing slack and tension of a chain 400' configured to run between a driving sprocket 200' and a driven sprocket 300'. The apparatus 100' comprises a spring that needs to be adjusted periodically to vary the stiffness of the spring, thereby removing the slack of the chain 400'.

[0027] Referring to FIGS. 2-4, an apparatus (100) for removing slack and vibration of a chain drive 1000 according to an embodiment of the present disclosure is shown. The apparatus 100 has a first end 100a and a second end 100b. The apparatus 100 includes a piston-cylinder device having a first piston 10 configured to slide within a cylinder 20 along a cylinder longitudinal axis A. The first piston 10 is configured to be actuated by the pressure of a first fluid. In a preferred embodiment, the first fluid is grease. A second piston 30 is configured to slide within a cavity 40 defined inside the first piston 10. The second piston 30 is configured to be actuated by the pressure of a second fluid. In a preferred embodiment, the second fluid is silicone oil. The cavity 40 is oriented along an axis that coincides with the longitudinal axis A of the cylinder 20. The cavity 40 contains silicone oil and is configured to be in fluid communication with the second piston 30. Accordingly, both the first piston 10 and the second piston 30 are configured to be displaced along the longitudinal axis A of the cylinder 20. A lubricating oil passage 50 is provided within the apparatus 100. The lubricating oil passage 50 is defined to penetrate through the first piston 10, the second piston 30, and the cylinder 20. The lubricating oil passage 50 is L-shaped. The first end 50a of the lubricating oil passage 50 terminates in a region where the first piston 10 and the sprocket wheel 80 are configured to interact. The second end 50b of the lubricating oil passage 50 terminates on the outer surface of the cylinder 10. Since the first piston 10 and the cylinder 20 have relative motion configured with respect to each other, the portion of the lubricating oil passage 50 on the cylinder 10 is displaced from the portion of the lubricating oil passage 50 at an instant during the operation of the apparatus 100. This ensures an intermittent supply of lubricating oil to the sprocket wheel 80. The second end 50b is configured to be coupled to a lubricating oil reservoir 60 from which lubricating oil is supplied to the chain drive. A throttle valve 52 is coupled to the second end 50b of the lubricating oil passage 50, which facilitates measurement of the amount of lubricating oil consumed from the lubricating oil reservoir 60. A grease port 70 is provided at one end of the cylinder 20 to facilitate a pressurized grease supply housed within a grease dispenser 74.The cylinder 20 is provided with a pressure sensor 72 for detecting the pressure of the grease within the cylinder 20. The first piston 10 is configured to be in fluid communication with the grease passing through the grease port 70. A seal is provided between the second piston 30 and the first piston 10 to prevent leakage of the silicone oil housed within the cavity 40.

[0028] In another embodiment, the apparatus 100 is configured simultaneously on a plurality of chain drives (1000). This is achieved by centrally installing the apparatus 100, thereby facilitating removal of slack and attenuation of vibration as well as lubrication to the plurality of chains 400.

[0029] Here, the operation of the apparatus will be described with the aid of FIGS. 2 to 4. The chain drive 1000 is shown in FIG. 2. The drive sprocket 200 and the driven sprocket 300 are arranged at a desired distance from each other. The drive sprocket 200 and the driven sprocket 300 are connected by a power transmission chain 400. The apparatus 100 is assembled on the slack side of the chain 400. By pressurizing the cylinder 20 with the grease from the grease port 70, the slack of the chain 400 is removed. Accordingly, the initial tension of the chain 400 is maintained at a desired level. The second piston 30 is pushed towards the second end 100b of the apparatus 100. Typically, a displacement of 10 mm is applied to the second piston 30 towards the second end 100b. This compresses the silicone oil within the cavity 40 towards the second end 100b. As the fluid within the cavity 40, silicone oil is selected due to its excellent compression characteristics.

[0030] When the chain drive 1000 starts operating, a thrust acts on the sprocket wheel 80 connected to the second piston 30, thereby pushing the second piston 30 from the first end 100a to the second end 100b. This results in the compression of the silicone oil within the cylinder 20 between the first piston 10 and the second piston 30. Upon the start of the chain drive 1000, after sustaining the initial acceleration and deceleration, when the chain 400 reaches a constant speed, the thrust incident on the second piston 30 decreases. Subsequently, the silicone oil exerts a force on the second piston 30 from the second end 100b to the first end 100a, thereby pushing the chain 400 into the average position on the drive sprocket 200 as well as the driven sprocket 300. Thus, vibrations are minimized with the aid of the second piston 30 that reciprocates inside the first piston 10. Figure 3 shows the moment when the lubricating oil passage 50 is blocked, and Figure 4 shows the moment when the lubricating oil passage 50 transfers lubricating oil from the lubricating oil reservoir 60 to the sprocket wheel 80. As shown in Figure 4, the portion of the lubricating oil passage 50 on the cylinder 20 is aligned with the portion of the lubricating oil passage 50 on the second piston 30. When the second piston 30 reciprocates inside the first piston 10, an intermittent supply of lubricating oil is effected, which eliminates the need for frequent manual intervention for the same purpose. When the sprocket wheel 80 is configured to mesh with the chain 400 of the chain drive 1000, the lubricating oil is transferred from the device 100 to the chain 400 of the chain drive 1000.

[0031] When the chain drive 1000 is used for a long time, the slack of the chain 400 of the chain drive 1000 increases, and it becomes necessary for the first piston 10 to be displaced from the second end portion 100b toward the first end portion 100a. This is required to remove the slack and ensure the desired tension of the chain 400 of the chain drive 1000. This is achieved by pumping grease through the grease port 70 toward the second end portion 100b of the device 100. The pressure sensor 72 constantly detects the pressure of the grease in the cylinder 20 acting on the first piston 10. The slack of the chain 400 causes a decrease in the pressure of the grease contained in the cylinder 20. The pressure sensor 72 sends a signal to the pump 76 attached in the grease reservoir to raise the pressure of the grease to a desired level in the cylinder 20. The desired pressure level of the grease in the cylinder 20 is calibrated with respect to the tension of the chain 400 of the chain drive 1000. Accordingly, the slack of the chain 400 of the chain drive 1000 is removed and an optimal tension is achieved, thereby reducing unnecessary vibrations harmful to the life of the chain drive 1000.

[0032] The description of the above embodiments is provided for illustrative purposes and is not intended to limit the scope of the present disclosure. The individual components of a particular embodiment are generally not limited to that particular embodiment and are interchangeable. Such modifications should not be regarded as a departure from the present disclosure, and all such changes are considered to be within the scope of the present disclosure.

[0033] Technological progress The present disclosure described above in this specification has several technical advantages including, but not limited to, the realization of a device for removing slack and vibration of a chain of a chain drive. · Eliminate frequent maintenance and service of the chain drive; · Eliminate the need for skilled labor; and · Improve chain drive performance by removing unnecessary vibrations.

[0034] The foregoing disclosure has been described with reference to the accompanying embodiments that do not limit the scope and area of the present disclosure. The provided description is by way of pure example and illustration.

[0035] The embodiments herein, as well as their various features and advantageous details, are described with reference to non-limiting embodiments in the following description. To avoid unnecessarily obscuring the embodiments herein, descriptions of well-known components and processing techniques are omitted.

[0036] The foregoing description of specific embodiments is to sufficiently clarify the general nature of the embodiments herein, so that others, by applying current knowledge, can readily modify and / or adapt such specific embodiments to various uses without departing from the general concept, and thus such adaptations and modifications should be understood to be within the meaning and scope of the equivalents of the disclosed embodiments and are so intended. It should be understood that the expressions or terms used herein are for purposes of description and not of limitation. Accordingly, although the embodiments herein have been described with respect to the preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modifications within the spirit and scope of the embodiments described herein.

[0037] Although considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be understood that many embodiments can be made and that many changes can be made to the preferred embodiments without departing from the principles of the present disclosure. These and other changes in the preferred and other embodiments of the present disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it should be clearly understood that the foregoing description is to be construed as illustrative of the present disclosure and not as a limitation.

Claims

1. An apparatus (100) for removing slack and vibration of a chain (400) of a chain drive (1000), configured to transmit the slack and vibration of the chain via a sprocket wheel (80) connected to the chain (400), - a piston-cylinder device, - a first piston (10) and a cylinder (20) configured for the first piston (10) to reciprocate, the cylinder (20) being configured to be filled with a first fluid, a grease port (70) defined in the cylinder (20) for introducing and distributing the first fluid into or from the cylinder (20), a pump (76) in fluid communication with the grease port (70), and a pressure sensor (72) mounted in the cylinder (20) for detecting the pressure of the first fluid in the cylinder (20), the pressure sensor (72) being configured to communicate with the pump (76), the pressure sensor (72) being configured to detect a pressure reduction in the cylinder (20) in response to slack of the chain (400), thereby detecting a decrease in the pressure exerted by the first piston (10) on the first fluid in the cylinder (20), and the grease port (70) being configured to enable the operation of the pump (76) when this occurs, the pressure sensor; - a second piston (30) configured to reciprocate within a cavity (40) defined inside the first piston (10), the second piston (30) being connected to the sprocket wheel (80) at one end (100a), a second compressible fluid being filled in the cavity (40), and the device of the second piston (30) being configured such that vibrations received by the second piston (30) are attenuated by the second compressible fluid. The apparatus (100) comprises a second piston (30).

2. The lubricating oil passage (50) is drilled through the second piston (30) and the cylinder (20), a first end (50a) of the lubricating oil passage (50) terminates at the engagement point with the sprocket wheel (80), and a second end (50b) is connected to a lubricating oil reservoir (60) for supplying lubricating oil to the engagement point. The apparatus (100) according to Claim 1.

3. The apparatus (100) according to claim 1, wherein the lubricating oil passage (50) is L-shaped.

4. The apparatus (100) according to claim 1, wherein a throttle valve (52) is provided at one end of the lubricating oil passage (50).

5. The apparatus (100) according to claim 1, wherein the second fluid is silicone oil.

6. The apparatus (100) according to claim 1, wherein the apparatus (100) is configured to be simultaneously formed on a plurality of chain drives (1000).

7. The apparatus (100) according to claim 1, wherein the orientation of the longitudinal axis (A) of the first piston (10), the second piston (30), and the (cylinder 20) with respect to the chain (400) is variable.

8. The apparatus (100) according to claim 1, wherein the apparatus (100) is configured to be supported by a fixture for the chain drive (1000).

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