Description:TECHNICAL FIELD
[0001] The present disclosure relates generally to the field of manufacturing splined components. In particular, the present disclosure relates to method for cold forming of splines and a simple, compact, and efficient tool for cold forming of splines on a pre-machined bank.

BACKGROUND
[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[0003] The conventional manufacturing of splines has relied heavily on traditional metal cutting methods, such as shaping, milling and hobbling operations. These methods, while effective to a degree, often pose limitations in terms of precision, efficiency, and versatility. Splines, essential components in various mechanical systems, including gearboxes, transmissions, and power transmission systems, play a critical role in ensuring smooth torque transmission and rotational motion. However, the metal cutting conventional techniques for producing splines have inherent drawbacks, such as requiring dedicated special purpose machines for shaping or hobbing of splines, whereas the general-purpose milling machines are slow and time consuming.
[0004] The existing methods often require multiple setups and tool changes, leading to increased production times and setup costs. Additionally, the reliance on material cutting process results in material wastage, contributing to higher production costs and environmental concerns.
[0005] There is, therefore, a well-established need in the art for a new method for manufacturing to overcome the above-mentioned problems by providing a simple, compact, and efficient tool for cold forming of splines on a pre-machined bank.

OBJECTS OF THE PRESENT DISCLOSURE
[0006] A general objective of the present disclosure is to overcome the problems associated with conventional methods for manufacturing splined components.
[0007] An objective of the present disclosure is to provide a method for manufacturing splines that can replace metal cutting operations during the manufacture of splines.
[0008] Another objective of the present disclosure is to provide a method for manufacturing splines by cold forming.
[0009] Another objective of the present disclosure is to provide a tool for use during manufacturing splines by cold forming that is simple, compact, efficient, and cost-effective.

SUMMARY
[0010] Aspects of the present disclosure pertain to the field of splined components. In particular, the present disclosure pertains to a method for manufacturing splines by cold forming, replacing the conventional method of manufacturing splines by metal cutting operations. In an aspect, a tool to be used for cold forming of splines on a machined blank is also disclosed.
[0011] In an aspect, a tool for cold forming of splines on a pre-machined blank includes an annular shaped die holder and an annular shaped die that is concentrically fixed to the die holder. An inner circumference of the annular shaped die includes a splined profile that matches the profile of the splines to be formed. The tool is configured to concentrically locate the blank over the die. The blank includes a gear portion and a spline portion. The blank is positioned over the tool where the spline portion of the blank engages with an outer end of the splined profile of the die. The splined profile of the die deforms the spline portion of the blank to generate the splines, when the blank is forced against the die.
[0012] In an embodiment, the blank may include an undercut between the gear portion and the spline portion. The undercut may be configured for accommodating material flow taking place due to deformation of the spline portion of the blank during generation of the splines.
[0013] In an embodiment, at least a portion of the undercut may be located on a surface of the gear portion that is adjacent and perpendicular to the spline portion. The material from the spline portion that flows radially outwards may be accommodated within the undercut of the gear portion.
[0014] In an embodiment, the tool may include a component ejector. The component ejector may be slidably configured with an inner diameter of the die holder. The component ejector may be projecting within an inner space of the die.
[0015] In an embodiment, the tool may include a locating bush. The locating bush may be concentrically fixed on an upper side of the component ejector. The locating bush may project beyond an upper side of the die to concentrically locate the pre-machined blank.
[0016] In an embodiment, the tool may include a punch. The punch may be configured for forcing the blank against the die.
[0017] According to another aspect of the present disclosure, a method for cold forming of splines on a blank includes step of pre-machining the blank where the blank includes a gear portion, a spline portion and an undercut located between the gear portion and the spline portion. The method further includes the step of positioning the blank within a tool where the tool includes an annular shaped die where a splined profile which matches the profile of splines is formed on an inner circumference of the annular shaped die. The tool is configured to concentrically locate the blank over the die. The blank is positioned over the die where the spline portion of the blank engages with an outer end of the splined profile of the die. The method further includes a step of forcing the blank against the die where the splined profile of the die deforms the spline portion of the blank to generate the splines at least partially, and the deformed material gets accommodated within the undercut during deformation of the spline portion of the blank.
[0018] In an embodiment, the method includes a step of pre-machining the blank. The pre-machining of the blank may include machining of the undercut where at least a portion of the undercut may be located on a surface of the gear portion that is adjacent and perpendicular to the spline portion. The material from the spline portion flowing radially outward may be accommodated within the undercut of the gear portion.
[0019] In an embodiment, the method includes a step of turning the blank. The turning of the blank may be to remove excess of the deformed material that remains around the bank.
[0020] In an embodiment, the method may include: repeating the steps of forcing the blank against the die with in-between turning of the blank to remove the excess of the deformed material till a complete length of the splines is generated.
[0021] In alternate embodiments, the in-between turning of the blank to remove the excess of the deformed material may be skipped.
[0022] In an embodiment, the method may include the step of post-machining of the blank. The post-machining may be performed on the blank to machine off any excess of the deformed material that remains outside of the undercut.
[0023] Various objects, features, aspects, and advantages of the subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.

BRIEF DESCRIPTION OF DRAWINGS
[0024] The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure. The diagrams are for illustration only, which thus is not a limitation of the present disclosure.
[0025] FIGs. 1A and 1B illustrate exemplary schematic views of the proposed tool for cold forming of splines on a pre-machined bank, in accordance with embodiments of the present disclosure.
[0026] FIGs. 2A to 2C illustrate exemplary schematic views of the blank without splines and blank with cold formed splines, in accordance with embodiments of the present disclosure.
[0027] FIGs. 3A to 3G illustrate exemplary schematic views showing different stages of the blank undergoing the cold forming showing progress of formation of the splines on the blank, in accordance with embodiments of the present disclosure.
[0028] FIG. 4 illustrates an exemplary flow diagram for the disclosed method for cold forming of splines on a pre-machined blank, in accordance with embodiments of the present disclosure.

DETAILED DESCRIPTION
[0029] For the purpose of promoting an understanding of the principles of the present disclosure, reference will now be made to the various embodiments and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the present disclosure is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the present disclosure as illustrated therein being contemplated as would normally occur to one skilled in the art to which the present disclosure relates.
[0030] It will be understood by those skilled in the art that the foregoing general description and the following detailed description are explanatory of the present disclosure and are not intended to be restrictive thereof.
[0031] Whether or not a certain feature or element was limited to being used only once, it may still be referred to as “one or more features” or “one or more elements” or “at least one feature” or “at least one element.” Furthermore, the use of the terms “one or more” or “at least one” feature or element do not preclude there being none of that feature or element, unless otherwise specified by limiting language including, but not limited to, “there needs to be one or more…” or “one or more elements is required.
[0032] Reference is made herein to some “embodiments.” It should be understood that an embodiment is an example of a possible implementation of any features and/or elements of the present disclosure. Some embodiments have been described for the purpose of explaining one or more of the potential ways in which the specific features and/or elements of the proposed disclosure fulfil the requirements of uniqueness, utility, and non-obviousness.
[0033] Use of the phrases and/or terms including, but not limited to, “a first embodiment,” “a further embodiment,” “an alternate embodiment,” “one embodiment,” “an embodiment,” “multiple embodiments,” “some embodiments,” “other embodiments,” “further embodiment”, “furthermore embodiment”, “additional embodiment” or other variants thereof do not necessarily refer to the same embodiments. Unless otherwise specified, one or more particular features and/or elements described in connection with one or more embodiments may be found in one embodiment, or may be found in more than one embodiment, or may be found in all embodiments, or may be found in no embodiments. Although one or more features and/or elements may be described herein in the context of only a single embodiment, or in the context of more than one embodiment, or in the context of all embodiments, the features and/or elements may instead be provided separately or in any appropriate combination or not at all. Conversely, any features and/or elements described in the context of separate embodiments may alternatively be realized as existing together in the context of a single embodiment.
[0034] Any particular and all details set forth herein are used in the context of some embodiments and therefore should not necessarily be taken as limiting factors to the proposed disclosure. The terms “comprises,” “comprising,” or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such process or method. Similarly, one or more devices or sub-systems or elements or structures or components proceeded by “comprises... a” does not, without more constraints, preclude the existence of other devices or other sub-systems or other elements or other structures or other components or additional devices or additional sub-systems or additional elements or additional structures or additional components.
[0035] Embodiments explained herein relate to a method for manufacturing splines on a splined component by cold forming, replacing the conventional metal cutting operations. In another embodiment, a tool for implementing the disclosed method is provided. The tool includes an annular shaped die holder which is concentrically fixed to the die holder, an inner circumference of the annular shaped die includes a splined profile that matches the profile of the splines to be formed on the blank. The blank is positioned over the tool such that a spline portion of the blank engages with an outer end of the splined profile of the die. The splined profile of the die deforms the spline portion of the blank when the blank is forced against the die to generate the splines.
[0036] In an embodiment, the machined blank for the splined component includes an undercut located on a surface of a gear portion, which gear portion is adjacent and perpendicular to the spline portion, such that the undercut can accommodate material that flows radially outwards from the spline portion during the cold forming of the spline portion for generation of the splines.
[0037] Referring to FIGs. 1A to 2C where the proposed tool 100 for cold forming of splines on a pre-machined blank is disclosed, the tool 100 can include an annular shaped die holder 102, and an annular shaped die 104 concentrically fixed to the die holder 102, where an inner circumference of the annular shaped die 104 includes a splined profile that matches the profile of the splines to be formed.
[0038] In an embodiment, the blank 300 can include a gear portion 302 and a spline portion 304 as shown in FIG.2A to FIG.2C. The tool 100 can be configured to concentrically locate the blank 300 over the die 104 such that the spline portion 304 of the blank 300 is engaged with an outer end of the splined profile of the die 104. The tool 100 in addition can include a component ejector 106 which can be slidably configured with an inner diameter of the die holder 102. In an exemplary embodiment, the die holder 102 can be configured on a bottom plate shown in FIG.1A and 1B. The component ejector 106 can be projected within an inner space of the die 104. The tool 100 can further include a locating bush 108 concentrically fixed on an upper side of the component ejector 106 such that the locating bush 108 may project beyond an upper side of the die 104 to concentrically locate the pre-machined blank 300 within the tool 100. The tool 100 can further include a punch 110 which can be configured for forcing the blank 300 against the die 104 for cold forming of splines. In an exemplary embodiment, the punch 110 can be fixed to a top plate, as shown in FIG. 1A and 1B, for being fixed to a ram of a press machine for moving the punch 110 downwards for forcing the blank 300 against the die 104 for cold forming of the splines.
[0039] In an embodiment, when the blank 300 is forced against the die 104, the splined profile of the die 104 can deform the spline portion 304 of the blank 300 to generate the splines. As deformation of material on the spline portion 304 takes place, the deformed material can flow radially outwards. The blank 300 can include an undercut 306 between the gear portion 302 and the spline portion 304 as shown in FIG.2A to 2C. The undercut 306 can accommodate material flow which is generated due to deformation of the spline portion 304 of the blank 300 during generation of the splines. Moreover, at least a portion of the undercut 306 can be located on a surface of the gear portion 302 which is adjacent and perpendicular to the spline portion 304 such that the undercut 306 can accommodate material that is flowing radially outwards from the spline portion 304 as shown in FIG. 2B.
[0040] FIG.3A to FIG.3G show different steps involved in generation of the splines through the cold stamping process, and as shown, the process of forcing the blank 300 against the die 104 for can be repeated a number of times, and some material can flow as a result of each step of forcing, as shown through the FIG.3A to FIG.3G, till splines are generated through the complete length of the spline portion 304.
[0041] FIG. 3A shows a turned blank 300 without splines before the start of the process of cold forming of the splines using the tool 100.
[0042] FIG.3B shows the punch 110 of the tool 100 forcing the turned bank 300, which is positioned on the tool 100, against the die 104 to form a first partially completed splines 308 through the cold stamping/ forming process. FIG. 3B also shows deformed material 310 that has flown radially outward as a result of the cold forming operation. In an embodiment, in applications where the complete length of the spline cannot be cold-formed in a single step of forcing the blank 300 against the die 104, the deformed material 310 that has flown radially outward as a result of the earlier cold forming operation can be removed by an in-between/ intermediate turning operation (also simply referred to as turning operation, herein) before the next cold forming operation is undertaken.
[0043] FIG.3C shows the blank 300 with partially formed splines 308 after the turning operation to remove excess deformed material 310 of FIG. 3B. The blank 300 can be removed from the tool 100 for the turning operation for removing the excess deformed material.
[0044] FIG.3D shows the blank 300 after a next cold forming operation after the turning operation, where, as can be seen, the partially completed splines 308 have been further extended and fresh deformed material 310 that radially extends has built up, which can be again removed by another intermediate turning operation, as shown in FIG. 3E, before undertaking the next cold forming operations till the completion of the splines 312 through the full length of the spline portion 304 of the blank 300, as shown in FIG. 3F.
[0045] The blank 300 with the completed splines can be further machined to remove any extra deformed material to get the finished splines on the blank 300, as shown in FOG. 3G.
[0046] According to an aspect, a method for cold forming of splines on a blank includes steps of pre-machining an input material to get the blank 300, positioning the blank 300 within the tool 100, forcing the blank against the die 104 of the tool 100, turning the blank 300 with partially formed splines 308 to remove the radially bulged deformed material 310, repeating the steps of forcing the blank 300 against the die 104 and turning off the deformed material 310 till full length of the splines 312 are formed.
[0047] Referring to FIG. 4, The proposed method 400 for cold forming of splines 312 on a blank can include, at block 402, the step of pre-machining the blank, such as the blank 300 shown in FIG. 3, where the blank 300 can include a gear portion 302, and a spline portion 304, and an undercut 306. The undercut 306 can be located between the gear portion 302 and the spline portion 304 and is configured to accommodate the material deformed during the cold forming.
[0048] The method 400 can further include, at block 404, the step of positioning the blank 300 within a tool 100, such as the tool 100 shown in FIG. 1. The tool 100 can include an annular shaped die 104, where an inner circumference of the annular shaped die 104 includes a splined profile that matches the profile of the splines to be formed on the blank 300. The tool 100 can be configured to concentrically locate the blank 300 over the die 104. The blank 300 can be positioned over the die 104 such that the spline portion 304 of the blank 300 is in engagement with an outer end of the splined profile of the die 104.
[0049] At block 406 of the method 400, the blank 300 can be forced against the die 104, where the splined profile of the die 104 can deform the spline portion 304 of the blank 300 to generate the splines, at least partially, such as partial splines 308 shown in FIG. 3 C and 3D. The deformed material, such as the deformed material 310 shown in FIG. 3 C and 3D, can be accommodated within the undercut 306 when the complete splines 312 have been formed.
[0050] In an embodiment, the step 402 of pre-machining of the blank 300 can include machining an undercut 306 such that at least a portion of the undercut 306 is located on the surface of the gear portion 302. The gear portion can be adjacent and perpendicular to the spline portion 304, such that the undercut 306 can accommodate the radially outward deformed material therewithin.
[0051] In an embodiment, the method 400 can also include one or more steps of intermediate turning operations after cold forming operations, where the radially bulging deformed material around the blank 300 can be removed before further cold forming operations.
[0052] In an embodiment, the method 400 can also include one or more repeat cold forming operations by punching the die 104 against the blank 300 for deepening the forming of splines. The steps of intermediate turning operations and the repeat cold forming operations can be repeated until the complete length of the splines is generated.
[0053] In another embodiment, when the full length of the spline is generated after the last of the cold forming operation, the deformed material can get accommodated within the undercut 306. In another embodiment, even after the last of the cold forming operations a turning operation can be performed to smoothen the surface of the gear portion 302 to remove any extra material and get a smooth surface.
[0054] While the foregoing describes various embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions, or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

ADVANTAGES OF THE INVENTION
[0055] The present disclosure overcomes the problems associated with conventional methods for manufacturing splined components.
[0056] The present disclosure provides a method for manufacturing splines that can replace metal cutting operations during the manufacture of splines.
[0057] The present disclosure provides a method for manufacturing splines by cold forming.
[0058] The present disclosure provides a tool for use during manufacturing splines by cold forming that is simple, compact, efficient, and cost-effective.

, Claims:

1. A tool for cold forming of splines on a pre-machined blank, the tool (100) comprising:
an annular shaped die holder (102);
an annular shaped die (104) concentrically fixed to the die holder (102), an inner circumference of the annular shaped die (104) comprising splined profile matching profile of the splines to be formed;
wherein the tool (100) is configured to concentrically locate the blank (300) over the die (104);
wherein the blank (300) comprises a gear portion (302) and a spline portion (304), and wherein the blank (300) is positioned over the tool (100) such that the spline portion (304) of the blank (300) is engagement with an outer end of the splined profile of the die (104); and
wherein, when the blank (300) is forced against the die (104), the splined profile of the die (104) deforms the spline portion of the blank (300) to generate the splines.

2. The tool (100) as claimed in claim 1, wherein the blank (300) comprises an undercut (306) between the gear portion (302) and the spline portion (304), the undercut (306) being configured to accommodate material flow taking place due to deformation of the spline portion (304) of the blank (300) during generation of the splines.

3. The tool (100) as claimed in claim 2, wherein at least a portion of the undercut (306) is located on a surface of the gear portion (302) that is adjacent and perpendicular to the spline portion (304), such that a radially outwards material flow from the spline portion (304) is accommodated within the undercut (306).

4. The tool (100) as claimed in claim 1, wherein the tool (100) comprises a component ejector (106) slidably configured with an inner diameter of the die holder (102) and projecting within an inner space of the die (104).

5. The tool (100) as claimed in claim 2, wherein the tool (100) comprises a locating bush (108) concentrically fixed on an upper side of the component ejector (106) such that the locating bush (108) projects beyond an upper side of the die (104) to concentrically locate the pre-machined blank (300).

6. The tool (100) as claimed in claim 1, wherein the tool (100) comprises a punch (110) configured for forcing the blank (300) against the die (104).

7. A method (400) for cold forming of splines on a blank, the method (400) comprising step of:
pre-machining (402) the blank (300), the blank (300) comprising a gear portion (302), a spline portion (304) and an undercut (306) that is located between the gear portion (302) and the spline portion (304);
positioning (404) the blank (300) within a tool (100), the tool (100) comprising an annular shaped die (104), an inner circumference of the annular shaped die (104) comprising splined profile matching profile of the splines to be formed; wherein the tool (100) is configured to concentrically locate the blank (300) over the die (104), and the blank (300) is positioned over the die (104) such that the spline portion (304) of the blank (300) is engagement with an outer end of the splined profile of the die (104); and
forcing (406) the blank (300) against the die (104) such that the splined profile of the die (104) deforms the spline portion (304) of the blank (300) to generate the splines at least partially, wherein during deformation of the spline portion (304) of the blank (300), the deformed material gets accommodated within the undercut (306).

8. The method (400) as claimed in claim 7, wherein the step of pre-machining (402) the blank (300) comprises, machining the undercut (306) such that at least a portion of the undercut (306) is located on a surface of the gear portion (302) that is adjacent and perpendicular to the spline portion (304), such that a radially outward material flow from the spline portion (304) is accommodated within the undercut (306).

9. The method (400) as claimed in claim 7, wherein the method (400) comprises the step of turning the blank (300) to remove excess of a radially deformed material that bulges around the bank (300).

10. The method (400) as claimed in claim 7, wherein the method (400) comprises repeating the steps of forcing the blank (300) against the die (104) and the step of turning till a complete length of the splines is generated and the deformed material is accommodated within the undercut (306).

11. The method (400) as claimed in claim 7, wherein the method (400) comprises the step of post-machining of the blank (300) to machine off any excess of the deformed material that remains outside of the undercut (306).

12. A method (400) for cold forming of splines on a blank, the method (400) comprising step of:
pre-machining (402) the blank (300), the blank (300) comprising a gear portion (302), a spline portion (304);
positioning (404) the blank (300) within a tool (100), the tool (100) comprising an annular shaped die (104), an inner circumference of the annular shaped die (104) comprising splined profile matching profile of the splines to be formed; wherein the tool (100) is configured to concentrically locate the blank (300) over the die (104), and the blank (300) is positioned over the die (104) such that the spline portion (304) of the blank (300) is engagement with an outer end of the splined profile of the die (104); and
forcing (406) the blank (300) against the die (104) such that the splined profile of the die (104) deforms the spline portion (304) of the blank (300) to generate the splines till a partial length of the spline portion (304);
machining off a radially bulged deformed material (310);
repeating the steps of positioning (404) the blank (300) within the tool (100), forcing (406) the blank (300) against the die (104) and machining off a radially bulged deformed material (310) till the splines are generated on the full length of the spline portion (304) of the blank (300).