DESC:FIELD OF INVENTION
[001] Present invention provides a replaceable mechanism for additive and subtractive manufacturing in a vertical machining center(VMC).
BACKGROUND OF INVENTION
[002] At present additive manufacturing and subtractive manufacturing has two separate machines specifically built for the purpose The main idea of implementing additive/subtractive manufacturing vertical machining center is to include additive manufacturing in a new or existing vertical machining center where subtractive manufacturing is the only possibility. This mechanism provides both the additive and subtractive machining capabilities to the machine. Subtractive manufacturing exist for a long time and hence the machine accuracies and machine reliability is significantly more. A vertical machining centre uses similar codes called as Mcodes and Gcodes for operating the machine. Similarly in an additive manufacturing machine, Gcodes and Mcodes are used to operate the machine. Hence without significant investment existing machining infrastructure can be optimally utilized by making use of the plug and play mechanism. Also the precision/resolution and quality of the manufactured part is higher due to the vertical machine construction compared to the additive manufacturing machines.

OBJECTIVES OF THE INVENTION
[003] Principle objective of the invention is to provide a replaceable mechanism for additive and subtractive manufacturing in a vertical machining center (VMC)
[004] Another objective of the invention is to provide an inclusion of additive manufacturing in vertical machining centre machines.
[005] Another objective of the invention is the machine can be used as either subtractive manufacturing or additive manufacturing by using replaceable mechanism.
[006] A further objective of the invention is to provide both additive and subtractive manufacturing using same hardware and electronics.
DESCRIPTION OF THE DRAWINGS
[007] Fig. 1 shows an embodiment of the present invention head portion of the machine where subtractive manufacturing tool is replaced by additive manufacturing tool. (21) Shows the head portion of the machine. (22) shows the heat sink. (23) shows the hot end. (24) Shows the nozzle.
[008] Fig. 2 Shows a prior art known setup of subtractive manufacturing in vertical machining center.(1) is the build area platform also called as bed. (2) is the replaceable subtractive manufacturing rotating tool head capable of motion along z axis, (3) is the head portion of the vertical machining center, (4) is the platform movable on X and Y axes and (5) is the filament inlet to the nozzle.

SUMMARY OF INVENTION
[009] According to the main aspect of the invention there is provided a replaceable mechanism for additive and subtractive manufacturing in a vertical machining center (VMC) comprising additive tool comprising a head (21), a heat sink (22) attached to the head (21) through a hole in the head (21), a hot end (23) attached to the heat sink (22), a nozzle (24) attached to the hot end (23), a tube (25) attached to (22) , the said heat sink (22) having hole at the lower end passing through the heating element (23), the said tube (25) having a filament running down to the hot end (23), the molten filament thereby flowing out through the nozzle (24).
[0010] According to another aspect wherein the hot end has an embedded heater.
[0011] According to yet another aspect wherein the filament is a melt able material.\
[0012] According to yet another aspect wherein the nozzle has a hole size of 0,2 mm

DETAILED DESCRIPTION
[0013] The invention involves the design of the tool attachment mechanism (Fig 1) having extruder which can be attached as and when necessary to the vertical machining center. This will enable the end user having both the features as necessary without new investment.
[0014] Present invention provides both additive manufacturing and subtractive manufacturing technologies in a single machine setup. This provides a great saving in machine cost, instead of manufacturing an additive manufacturing machine with new hardware and new microcontroller the present invention provides a gateway to use the same hardware and microcontroller present in the machines of vertical machining center. ,CLAIMS:We claim
1. A replaceable mechanism for additive and subtractive manufacturing in a vertical machining center (VMC) comprising additive tool comprising a head (21), a heat sink (22) attached to the head (21) through a hole in the head (21), a hot end (23) attached to the heat sink (22), a nozzle (24) attached to the hot end (23), a tube (25) attached to (22) , the said heat sink (22) having hole at the lower end passing through the heating element (23), the said tube (25) having a filament running down to the hot end (23), the molten filament thereby flowing out through the nozzle (24).
2. The replaceable mechanism as claimed in claim 1 wherein the hot end has an embedded heater.
3. The replaceable mechanism as claimed in claim 1 wherein the filament is a melt able material.
4. The replaceable mechanism as claimed in claim 1 wherein the nozzle has a hole size of 0,2 mm