METHOD OF MANUFACTURING CONVEYOR BELT PULLEY IN FORGING
Technical Field of the present invention:
The present invention disclosed herein is related to method of manufacturing an auto component conveyor belt pulley involving hot forging operation, wherein the said pulley is mainly applicable in motor cycle.
Background and objective of the present invention:
A pulley, also called a sheave or a drum, may have a groove between two flanges around its circumference. A rope, cable, belt, or chain usually runs over the wheel and inside the groove, if present. Pulleys are used to change the direction of an applied force, transmit rotational motion, or realize a mechanical advantage in either a linear or rotational system of motion. It is one of the six simple machines. Two or more pulleys together are called a block and tackle.
Conventionally, a belt and pulley system is characterized by two or more pulleys in common to a belt. This allows for mechanical power, torque, and speed to be transmitted across axles. If the pulleys are of differing diameters, a mechanical advantage is realized. A belt drive is analogous to that of a chain drive, however a belt sheave may be smooth (devoid of discrete interlocking members as would be found on a chain sprocket, spur gear, or timing belt) so that the mechanical advantage is approximately given by the ratio
of the pitch diameter of the sheaves only, not fixed exactly by the ratio of teeth as with gears and sprockets.
Rope and pulley systems (the rope may be a light line or a strong cable) are characterized by the use of one rope transmitting a linear motive force (in tension) to a load through one or more pulleys for the purpose of pulling the load (often against gravity.) They are often included in lists of simple machines.
One of the conventional applications of the conveyor belt pulley with grooves on its circumference, as depicted in Figure 1 herein below, is in motorcycles. Such pulleys are conventionally manufactured by casting process, followed by multiple machining processes. The schematic plan for manufacturing one embodiment of such pulley is shown in following schematic table:
CONVENTIONAL PROCESS:
(Table Removed)
Such conventional method of manufacturing the said pulley is associated certain drawbacks, namely:
1. Considerable amount of loss of pulley making metallic material (steel or steel based alloy material herein), mainly towards creating the cavity and cutting the grooves on the circumferential face therein;
2. The internal strength of the component is not comparatively high, mainly in terms of abrasion resistance.
It is a well known fact that forging gives better results than casting. Even then such pulleys are being produced by casting process. Forging provides some of the following benefits over casting process towards producing certain components like the concerned pulley component herein:
(i) Casting cannot obtain the strengthening effects of hot and cold working. Whether open or closed die forging is used, the forging process surpasses casting in predictable strength properties -producing superior strength that is assured, part to part.
(ii) A casting has neither grain flow nor directional strength and the process cannot prevent formation of certain metallurgical defects. Pre-working forge stock produces a grain flow oriented in directions requiring maximum strength. Dendritic structures, alloy segregations and like imperfections are refined in forging.
(iii) Casting defects occur in a variety of forms. Because hot forging refines grain pattern and imparts high strength, ductility and resistance properties, forged products are more reliable. And they are manufactured without the added costs for tighter process controls and inspection that are required for casting vs forging.
(iv) Castings require close control of melting and cooling processes because alloy segregation may occur. This results in non-uniform heat-treatment response that can affect straightness of finished parts. Forgings respond more predictably to heat treatment and offer better dimensional stability.
(v) Some castings, such as special performance castings, require expensive materials and process controls, and longer lead times. Open die forging and ring rolling are examples of forging processes that adapt to various production run lengths and enable shortened lead times.
Therefore the present invention is to propose a new method of manufacturing the said pulley with its grooves by using hot forging operation on horizontal hot former, which is performed by using a suitable die for the purpose at an optimized hot forging condition.
Main objective of the present invention is to propose a method of manufacturing the conveyor belt pulley with grooves by hot forging process on horizontal hot former, followed by certain optional machining and electrophoretic coating (ED coating) operations, mainly towards surface refining, surface protection and property enhancement therein.
Another objective of the present invention is to propose a pulley with grooves on its circumferential face, as depicted in Figure 1, which is formed by horizontal hot forging process and wherein the said pulley component is comparatively much advanced in its structural and functional properties, mainly in terms of internal structural strength, refined grain pattern of the material, no air pockets, uniform heat treatment during forging, higher ductility, abrasion & corrosion resistance properties.
Another objective of the present invention is to propose a new die, compatible to carry out the hot forging operation towards forming the said pulley with grooves, wherein said pulley formed is of variable optional dimension, diameter, shape, size, groove pattern, and surface pattern therein.
Statement of the present invention:
The present invention is primarily intended:
To propose a method of manufacturing the conveyor belt pulley with grooves by hot forging process on horizontal hot former, followed by
certain optional machining and electrophoretic coating (ED coating) operations, mainly towards surface refining, surface protection and property enhancement therein; and
to propose a pulley with grooves on its circumferential face, as depicted in Figure 1, which is formed by horizontal hot forging process and wherein the said pulley component is comparatively much advanced in its structural and functional properties, mainly in terms of internal structural strength, refined grain pattern of the material, no air pockets, uniform heat treatment during forging, higher ductility, abrasion & corrosion resistance properties; and
to propose a new die, compatible to carry out the hot forging operation towards forming the said pulley with grooves, wherein said pulley formed is of variable optional dimension, diameter, shape, size, groove pattern, and surface pattern therein.
Description of the present invention:
The present invention proposes a method for manufacturing a pulley by hot forging process on horizontal hot former, using a suitable closed die for carrying out the forging operation, wherein the said method preferably forms a pulley with its groove pattern on its circumferential face and desired surface pattern, as depicted in Figure 1. The schematic plan
i
proposed for manufacturing of one embodiment of the said pulley is shown in following table:
NEW proposed process:
(Table Removed)
Duly forged pulley component is subjected to CNC turning-l and CNC turning-l I operations, mainly to refine the grooves pattern and the surface of the component. After that, the pulley component undergoes electrophoretic coating (ED coating), which primarily helps in surface
protection of the said component from corrosion and other abrasive conditions during function.
After receiving the ED coating, final inspection of the said component is performed, followed by its oiling and packaging.
The novel concept and inventiveness, involved in the manufacturing process of one embodiment of the said conveyor belt pulley, preferably with grooves, may comparatively be understood by schematic flow-chart plan of the conventional method and the newly proposed method.
Figure 2 depicts the schematic plan of the conventional method, wherein casting of said pulley component is most significant step, followed by supporting machining and ED coating steps.
However, Figure 3 shows the presently proposed method of manufacturing the pulley mainly characterized by involvement of horizontal hot forging operation, in spite of casting, using the suitably designed die for the purpose. The hot forged pulley component, by way of CNC turning operations (I and II) is further refined towards its surface smoothening and cleaning/magnifying of the groove pattern therein. Subsequently the other surface protector-cum-smoothening process, that is, the ED coating is made on the said pulley component.
Scope of the present invention:
Although the invention has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternate embodiments of the invention, will become apparent to persons skilled in the art upon reference to the description of the invention. It is therefore contemplated that such modifications can be made without departing from the spirit or scope of the present invention as defined.

We claim:
1. A method of manufacturing conveyor belt pulley, preferably with the groove pattern, wherein the said method mainly involves horizontal hot forging process using suitable die for forming the said pulley component, followed by supporting processes, namely CNC turning and ED coating; and wherein the said method is characterized by the internal structure and strength of the said formed pulley component.
2. A method of manufacturing conveyor belt pulley, preferably with the groove pattern, as claimed in claim 1, wherein the said method is characterized by hot forging operation towards pulley formation and further characterized by not performing of the casting of said pulley.
3. A method of manufacturing conveyor belt pulley, preferably with the groove pattern, as claimed in claim 1, wherein the said hot forging operation applies a suitable closed die for creating structural features like central hole, the grooves pattern on the circumferential face of the pulley and other major surface elevations/depressions of the said pulley component.
4. A method of manufacturing conveyor belt pulley, preferably with the groove pattern, as claimed in claim 1, wherein the said pulley and its grooves pattern, optionally of different shape, size, dimension, groove profile, surface pattern and configuration is manufactured by the said method involving the horizontal hot forging process using suitable closed die of
corresponding optional shape, size, dimension, groove profile, surface pattern and configuration therein.
5. A method of manufacturing conveyor belt pulley, preferably with the groove pattern, substantially as herein described and illustrated in the figures of the accompanying drawings.