Abstract:
A roller chain may include a link having a pair of outer plates connected to a pair of pins, where one of the pins sufficiently extends outside the plate to facilitate connection with a stud and thereby provide connection for attachments.

Description:
RELATED APPLICATIONS 
       [0001]    This application is based on and claims priority to provisional U.S. Patent Application No. 61/583,480, filed Jan. 5, 2012, the contents of which are herein incorporated by reference. 
     
    
     FIELD OF THE DISCLOSURE 
       [0002]    The present disclosure is related to a stud connected to an extended pin on a link of a roller chain, a method of manufacturing an extended pin/stud combination on the link and a chain including the extended pin and stud, and more particularly, to a multi-component extended pin and stud coupled to a sidebar in a link of a roller chain, a method of manufacturing the link with the extended pin and stud and a chain including the link with the extended pin and stud. 
       BACKGROUND 
       [0003]    Roller chain is a type of chain drive designed for the transfer of mechanical power in many kinds of domestic, industrial and agricultural machinery, including conveyors, wire and tube drawing machines, printing presses, cars, motorcycles, and simple machines like bicycles. The chain is commonly driven by a toothed wheel called a sprocket. Commonly, a roller chain has a series of links designed to mesh with the teeth of the sprockets of the machine, and are flexible in only one dimension. Each link may include short cylindrical rollers held together by side links by an axle that is connected to the side links and passes through the rollers. It is a simple, reliable, and efficient means of power transmission. 
         [0004]    Generally, as shown in  FIGS. 1 and 2 , there are two types of links sequentially alternating in the roller chain A. The first type is an inner link B that has two parallel inner plates C held together by two axles or bushings D, press or interference fit to the inner plates, upon and about which two rollers F may rotate. Inner links A alternate with the second type, the outer links F, consisting of two outer plates G held together by pins H, press or interference fit to the outer plates, that pass through the bushings D of the inner links A. The roller chain design reduces friction compared to simpler designs, resulting in higher efficiency and less wear. The original power transmission chain varieties lacked rollers and bushings, with both the inner and outer plates held by pins which directly contacted the sprocket teeth; however this configuration exhibited extremely rapid wear of both the sprocket teeth, and the plates where they pivoted on the pins. This problem was partially solved by the development of bushed chains, with the pins holding the outer plates passing through bushings or sleeves connecting the inner plates. This distributed the wear over a greater area; however the teeth of the sprockets still wore more rapidly than is desirable, from the sliding friction against the bushings. The addition of rollers surrounding the bushing sleeves of the chain and provided rolling contact with the teeth of the sprockets resulting in excellent resistance to wear of both sprockets and chain as well. There is even very low friction, as long as the chain is sufficiently lubricated. Continuous, clean, lubrication of roller chains is of primary importance for efficient operation as well as correct tensioning. Carbon steel is a standard material of construction, but where corrosion protection or corrosion resistance are required, there are options of nickel plating, N.E.P. (carbon steel chain with a special multi layer protective coating), stainless steel and engineering plastic combinations. Lube-free chain is available for long term operation without the need for additional lubrication, particularly for sensitive industries such as food, beverage and pharmaceuticals. 
         [0005]    Attachments to the roller chain offer a whole range of possibilities for a chain designer or user. Virtually any chain can include attachment links, which allow users to fasten screws to the chain or accurately position products. The possibilities are limited only by the imagination of the designer or user. While there are numerous standard attachments available to fit roller chain, more specialized, function related attachments are often needed in order to provide conveying solutions for OEM manufacturers or final consumers. 
         [0006]    Common attachments may include an integrally formed or multi-piece constructed link sidebar that has an extended portion either in plane with the sidebar or normal to the plane of the sidebar or a link pin that extends well beyond the side bar. One conventional extended pin is a one-piece design that is connected to the link sidebar at one end. The remaining three pin ends are connected to the link side bars in a conventional manner. Some chain manufacturers recommend that the extended pin have no shoulder because the shoulder can compromise quality due to high stress concentrations at the point where diameters change. Such manufacturers believe that additions of sleeves or bearings on the extended pins will often yield a more dependable design. Another conventional one-piece extended pin design has a shoulder and an enlarged end. Generally, there are two steps in the pin diameter that allow the pin to be inserted into the side bar. The first step is a shoulder that is press or interference fit into a non-standard opening in one of the outer link side bars and connected to the other outer link side bar in a conventional manner. The second step is the portion of the roller chain pin that fits inside the roller chain bushing or axle. However, this design does have some disadvantages, namely, there are high stress concentrations, if the second stepped portion needs to be plated, then the pin must be masked at the time of plating and may need to be plunge ground after plating, the cost is often high due to the amount of scrap involved in making the one-piece pin design, the sidebar must have at least one hole specifically sized to accept the shoulder on the extended pin, and the extended pin can turn inside the sidebar when high loads are applied. 
         [0007]    Therefore, there is a need in the art for an extended pin design that overcomes the aforementioned disadvantages and provides lower costs. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The following disclosure as a whole may be best understood by reference to the provided detailed description when read in conjunction with the accompanying drawings, drawing description, abstract, background, field of the disclosure, and associated headings. Identical reference numerals when found on different figures identify the same elements or a functionally equivalent element. The elements listed in the abstract are not referenced but nevertheless refer by association to the elements of the detailed description and associated disclosure. 
           [0009]      FIG. 1  is a cross-section view of a conventional bush roller chain. 
           [0010]      FIG. 2  is an exploded view of a conventional bush roller chain. 
           [0011]      FIG. 3  is a top plan view of an outer link having an extended pin in accordance with one embodiment of the present disclosure with inner links removed for clarity. 
           [0012]      FIG. 4  is a top plan view of a stud or cap pin in accordance with one embodiment of the present disclosure. 
           [0013]      FIG. 5  is a side elevation view of the cap pin of  FIG. 4 . 
           [0014]      FIG. 6  is an end elevation view of the cap pin of  FIG. 4 . 
           [0015]      FIG. 7  is a top plan view of a chain formed of a series of outer and inner links and a combination of the extended pin of  FIG. 3  and the stud of  FIGS. 4-6  with a method of manufacturing. 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    The present disclosure is not limited to the particular details of the apparatus depicted, and other modifications and applications may be contemplated. Further changes may be made in the apparatus, device or methods without departing from the true spirit of the scope of the disclosure herein involved. It is intended, therefore, that the subject matter in this disclosure should be interpreted as illustrative, not in a limiting sense. 
         [0017]      FIG. 3  illustrates a top plan view of an outer link assembly  100  in accordance with one embodiment of the present disclosure. The outer link  100  may include a standard pin  102  and extended pin  106  that are each pressed into a standard sidebar  104  (i.e., having a pair of standard conventional openings) in what may be described as an interference fit or other suitable connection, such as, a press fit, friction fit, shrink fit, location fit, transition fit, engineering fit, force fit, precision fit (which shall all be commonly referred to as “interference fit” herein), as necessary to obtain or achieve the desired result as described herein. The standard pin  102  and the extended pin  106  may each have a continuous standard diameter and a portion  108  that projects from an exterior side  110  of the sidebar  104 . This portion  108  of the standard pin  102  is useful to additionally secure the connection of the pin  102  to the sidebar  104  in a known manner, such as, for example only, staking, riveting, spinning or any other suitable manner. The portion  108  of the extended pin  106 , however, is not useful to secure the connection to the sidebar  104  and projects a distance  150  further from the exterior side  110  than a distance  152  the portion  108  of the standard pin  102 . Preferably, in one embodiment the distance  150  may be 0.045 inches. The distance may have other dimensional configurations such that a suitable connection between portion  108  and stud  200  can be made such as, but not limited to, distances greater than 0.01 inches. The standard and extended pins  102 ,  106  may be plated, painted, other otherwise coated, treated, etc. in order to provide the desired functionality. In one embodiment, the pins  102 ,  106  maybe chrome or nickel plated to resist wear and provide increased durability. 
         [0018]      FIGS. 4 ,  5  and  6  respectively illustrate top, side and end views of a stud or cap pin  200  in accordance with one embodiment of the present disclosure. The stud  200  may include a main body  202 , a connection end  204 , and a free end  206 . Preferably, in one embodiment, the connection and free ends  204 ,  206  are parallel or non-parallel, as desired. The main body  202  preferably has a diameter that is greater than a diameter of the extended pin  106  to provide the functionality as described herein. Preferably, in one embodiment, the main body  202  diameter is greater than  1 . 1  times the diameter of the extended pin  106 . More preferably, the diameter of the main body  202  is greater than  1 . 5  times the diameter of the extended pin  106 . Most preferably the diameter of the main body  202  is greater than  2 . 0  times the diameter of the extended pin  106 . The connection end  204  may include a cavity  208 , a chamfer  210  and a shoulder  212 . The cavity  208  may be configured complementary to the portion  108  of the extended pin  106  such that the cavity  208  engages such portion  108  with an interference fit preferably or any other suitable connection manner. The chamfer  210  is disposed and extends from an exterior surface of the main body  202  to a point adjacent to but offset from a rim of the cavity  208  in order to define the shoulder  212  as an annulus disposed about the cavity  208 . Preferably, in one embodiment the shoulder or annulus  212  may be 0.143 inches. In other embodiments, annulus  212  may be 0.04 to 0.2 inches but other configurations can also be used depending on various factors such as, but not limited to, the overall size of the chain and the size of stud  200 . The stud  200  may also include in one or more embodiments, a feature, such as a bore  214  through the main body  202 , to facilitate connection with other components or attachments. The stud  200  may be may be plated, painted, other otherwise coated, treated, etc. in order to provide the desired functionality or left in raw finished form, as may be provided in one embodiment. As a result, the stud  200  may be manufactured with less scrap than the prior one-piece design and provide increased flexibility of design over prior attempts. 
         [0019]      FIG. 7  illustrates a top plan view of a chain  300  formed of a series of outer  100  and inner  312  links and a combination of the extended pin  106  of  FIG. 3  and the stud  200  of  FIGS. 4-6  with a method of manufacturing. The chain  300  is constructed in a conventional manner as described herein with respect to  FIGS. 1 and 2 , except the extended pin  106  is used in place of another standard pin for at least one of the outer links  100 . The inner links  302  are constructed in the conventional manner as described with respect to  FIGS. 1 and 2 . Then, the stud  200  is fitted to the portion  108  of the extended pin  106  after longitudinal alignment and registration, so that the stud  200  may engage such portion  108  as described herein. The stud  200  is preferably secured to the sidebar  104 , and the extended pin  106  is preferably secured to the sidebar  104  and the stud  200  by a single upset welding process or other suitable process or manner to achieve the desired result such that all three of the parts are fused together to prevent the pin  106  from turning inside the sidebar  104  and to maintain connection of the stud  200  to the pin  106 . Upset welding is a resistance welding process, in either a single-pulse or continuous mode, that utilizes both heat and deformation to form a weld. The heat is produced by resistance to the flow of electrical current at the interface of the abutting surfaces to be joined (i.e., the shoulder annulus  212  and sidebar  104 , the cavity  208  and portion  108  of the extended pin  106 , the extended pin  106  and the sidebar  104 ). The deformation results from force on the joint in combination with softening from the electrical resistance heat. Upset welding typically results in solid-state welds (no melting at the joint, which is not advantageous). The deformation at the weld joint provides intimate contact between clean adjoining surfaces, allowing formation of strong metallurgical bonds. If any melting does occur during upset welding, the molten metal is typically extruded out of the weld joint area, which is not desired in this disclosure, but is not detrimental as long as tolerances are maintained. Generally, wire, bar, strip, and tubing can be joined end to end with a single pulse of welding current. Whereas, seams on pipe or tubing can be joined using continuous upset welding by feeding a coiled strip into a set of forming rolls, resistance heating the edges with wheel electrodes, and applying a force to upset the edges together. A data acquisition system may be used to record the force, current, voltage, and motion of the weld head during welding. Equivalent welds may be made using both alternating and direct current. Upset welds have similar characteristics to inertia friction welds, which are also solid-state welds. The amount of deformation is usually less for upset welds, and the deformation can be more precisely controlled using upset welding. One benefit is that if the pin  106  must be plated, the cost is minimal because masking or subsequent plunge grinding is not necessary. 
         [0020]    Preferably, the outer link  100  may be formed partially with a single standard pin  102 , the extended pin  106  and a single standard side bar  104 , such that connection of the pin  106 , side bar  104  and stud  200  may be more easily accomplished and then incorporated into a roller chain  300  as would be understood by one of ordinary skill in the art for combination with another side bar  104  to complete the assembly of an outer link for the roller chain  300 . 
         [0021]    The preceding detailed description is merely some examples and embodiments of the present disclosure and that numerous changes to the disclosed embodiments can be made in accordance with the disclosure herein without departing from its spirit or scope. The preceding description, therefore, is not meant to limit the scope of the disclosure but to provide sufficient disclosure to one of ordinary skill in the art to practice the invention without undue burden.