Claims:1. Tool holder assembly for chamfering inside the shell used in Heat Exchanger comprising a tool holder (6) inserted in drilling machine spindle (16) with a guide base (11) placed 5 there between, wherein the tool holder (6) is provided with horizontal and vertical guide ways (7, 8) for guiding the guide bush (11) inserted onto the tool holder (6).
2. Tool holder assembly for chamfering inside the shell used in 10 Heat Exchanger as claimed in claim 1, wherein a cutting tool (13) is held firmly in cutting tool holding slot (9) by fastener including grub screw (15).
3. Tool holder assembly for chamfering inside the shell used in 15 Heat Exchanger as claimed in claim 1 or 2, wherein vertical guide way (7) is meant for sliding the guide bush (11) and the horizontal guide way (8) is provided for preventing the guide bush (11) from sliding down.
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4. Tool holder assembly for chamfering inside the shell used in Heat Exchanger as claimed in claims 1-3, wherein the guide bush (11) and the guide ways (7-8) facilitates for insertion and removal of the tool holder (6) into the hole to be chamfered, without the necessity for removing the tool holder (6) from the 25 spindle during each chamfering operation done on subsequent holes.
5. Tool holder assembly for chamfering inside the shell used in Heat Exchanger as claimed in claim 1-4, wherein said grub 30 screw (15) guides the guide bush (11) inside the guide ways
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(7-8).
6. Tool holder assembly for chamfering inside the shell used in Heat Exchanger as claimed in claim 1-5, wherein during inserting the tool holder (6) while machining, the guide bush 5 (11) is initially kept in the top position and while inserting the tool holder (6) into the bored hole, the center axis of the tool holder (6) and the bored hole is kept with slight offset that the cutting tool (13) does not interface with the shell (1), wherein the guide bush (11) is slided down and located to the center of 10 the bored hole.
7. Tool holder assembly for chamfering inside the shell used in Heat Exchanger as claimed in claim 1-6, wherein during removing the tool holder (6) after completion of machining, the 15 guide bush (11) is slided up first and then the tool holder (6) is brought out in the similar manner as done during insertion.
8. Tool holder assembly for chamfering inside the shell used in Heat Exchanger as claimed in the claims 1-7 is associated 20 with the advantageous features such as herein described. , Description:Tool holder assembly for chamfering inside the shell used in Heat Exchanger
FIELD OF INVENTION
[001] The present invention relates to tool holder assembly for chamfering inside the shell used in Heat Exchanger. More 5 particularly the present invention relates to development of a Tool Holder assembly for the chamfering operation in-order to provide a welding groove for the guide rod welding.
BACKGROUND OF THE INVENTION 10
[002] In the manufacturing of Heat Exchanger, there are two shells used namely inner shell and outer shell. The inner shell should be concentric to the outer shell. To ensure the concentricity, hex head 15 bolt rods are employed across the length of the shell. The bolt rods are threaded inside the guide rods which are welded with the inner shell. In order to weld the guide rod to the shell, a weld groove needs to be generated.
[003] Initially a hole of diameter equal to the outside diameter of 20 guide rod is drilled on the inner shell. Now to provide the weld groove, chamfering has to be made on both sides of the shell. Chamfering operation outside the shell is conducted using existing tool holder, whereas inside the shell in done by gas-cutting and grinding operation. Both the gas-cutting and grinding operation is 25 time consuming and laborious. Apart from the use of excess manpower, the material consumption like gas and grinding wheels are high. Grinding and gas-cutting operations also have negative impact on both human and environment. These operations create enormous fatigue at work and dimensional tolerance achieved is not 30 to the satisfactory level. At the end, customer satisfaction is very low. In order to overcome all the aforesaid problems, there is a need to
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develop a new tool holder assembly for the inside chamfering operation.
[004] Hence, the present invention has been introduced, which can efficiently serve the purpose without being associated with any of the above drawbacks. 5
OBJECTS OF THE INVENTION
[005] An object of the invention is to propose tool holder assembly 10 for chamfering inside the shell used in Heat Exchanger which obviates shortcomings of the prior art(s).
[006] Another object of the invention is to propose tool holder assembly for chamfering inside the shell used in Heat Exchanger which is simple and efficient. 15
[007] Still another object of the present invention is to provide tool holder assembly for chamfering inside the shell used in Heat Exchanger which can enter the hole provided for guide rod.
[008] Yet another object of the present invention is to develop tool holder assembly for chamfering inside the shell used in Heat 20 Exchanger in such a way that subsequent chamfering operation is done without the need to remove either the cutting tool from the tool holder or the tool holder from the drilling machine spindle.
SUMMARY OF THE INVENTION 25
[009] Accordingly, there is provided tool holder assembly for chamfering inside the shell used in Heat Exchanger comprising a tool holder inserted in drilling machine spindle with a guide base placed there between, wherein the tool holder is provided with 30 horizontal and vertical guide ways for guiding the guide bush inserted onto the tool holder.
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[010] A cutting tool is held firmly in cutting tool holding slot by fastener including grub screw.
[011] Vertical guide way is meant for sliding the guide bush and the horizontal guide way is provided for preventing the guide bush from sliding down. 5
[012] The guide bush and the guide ways facilitates for insertion and removal of the tool holder into the hole to be chamfered, without the necessity for removing the tool holder from the spindle during each chamfering operation done on subsequent holes.
[013] Said grub screw guides the guide bush inside the guide ways. 10
[014] During inserting the tool holder while machining, the guide bush is initially kept in the top position and while inserting the tool holder into the bored hole, the center axis of the tool holder and the bored hole is kept with slight offset that the cutting tool does not interface with the shell, wherein the guide bush is slided down and 15 located to the center of the bored hole.
[015] During removing the tool holder after completion of machining, the guide bush is slided up first and then the tool holder is brought out in the similar manner as done during insertion.
[016] Now, to carry out the chamfering operation the tool holder 20 with all the above setup is inserted into the bored hole. The guide bush is then released down by sliding the grub screw of the guide bush in the vertical guide way, thus ensuring the tool holder in the center of bored hole. Then inside chamfering is completed by feeding the tool against the shell. In-order to chamfer the next hole, the 25 guide bush is slided-up and kept in the top position by moving the grub screw in the horizontal guide way. Then the tool holder is pulled out of the chamfered hole without hitting the cutting tool against the shell.
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BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
[017] Further objects and advantages of this invention will be more apparent from the ensuing description when read in conjunction with the accompanying drawings of the exemplary embodiments and wherein:- 5
Figure 1 shows: The inner shell with guide rod in position and external chamfering.
Figure 2 shows: The guide rod welded to the inner shell.
Figure 3 shows: the cross section of the chamfered hole with 10 external and internal chamfers.
Figure 4 shows: The elevation of the tool holder with horizontal and vertical guide ways, wherein threaded holes for fastening the grub screws which holds the cutting tool firmly with the tool holder and the 15 view A in the figure shows cutting tool slot and wedge slot.
Figure 5 shows: The guide Bush with threaded hole.
Figure 6 shows: The cutting tool used in the tool holder for inside chamfering. 20
Figure 7 shows: The wedge.
Figure 8 shows: The grub screw used in the guide bush and tool holder.
Figure 9 shows: The tool holder assembly locked in the drilling Machine spindle using the wedge and the guide 25 bush and cutting tool in their working condition.
Figure 10 shows: The operations involved during insertion of the tool holder while machining.
Figure 11 shows: The operations involved during removal of the tool holder after completion of machining. 30
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DETAIL DESCRIPTION OF THE PRESENT INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWINGS OF PREFERRED EMBODIMENTS
[018] The present invention discloses a technology implemented in 5 heat exchanger. Specifically, the technology is pertinent to a tool holder assembly.
[019] The novel tool holder assembly of the instant invention is employed for the chamfering so as to provide a welding groove for the guide rod welding. The chamfering operation is carried out inside 10 the shell used in heat exchanger.
[020] Now, the invention will be discussed herein under.
[021] A shown in Figure 1, the shell (1) of heat exchanger is drilled using a taper shank twist drill in conventional drilling machine as per the marking made on the shell (1). The drilled hole is then bored 15 to a diameter that suits the outside diameter of the guide rod (2) as illustrated in figure 2. Outside Chamfering (3) to 45degrees on the shell (1) as shown in Figure 3, to a depth of 8mm is done using a known tool holder.
[022] Now, reference may be made to fig. 9 indicating assembly of 20 the developed tool holder (6) inserted in the drilling machine spindle (16). The spindle (16) and the tool holder (6) are inter-locked by means of a wedge (14) in the wedge slot (10) provided in the spindle (16). The wedge (14) is separately shown in figure 7. Here, the wedge (14) is placed horizontally i.e. in a direction orthogonal to the spindle 25 (16). There is provision of guide bush (11) between the spindle (16) and tool holder (16). As shown in the figure 9 the guide bush (11) is inserted on to the tool holder (6) and is guided in the guide ways (7)(8) of the tool holder (6) using a grub screw (15) fastened in the threaded hole (12) as shown in figure 5, wherein the tool holder (6) 30
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is provided with horizontal and vertical guide ways (7, 8) for guiding the guide bush (11).
[023] Figure 5 and Figure 8 shows the guide bush (11) and grub Screw (15) respectively. The plain end of the grub screw (15) travels in the guide ways (7)(8) provided on the tool holder (6). To prevent 5 the guide bush (11) from sliding down, the plain end of the grub screw (15) after reaching the top end of the vertical guide way (7) is slided into the horizontal guide way (8). The elevation of the designed tool holder (6) can be best seen in Figure 4. The vertical guide way (7) and horizontal guide way (8) for sliding the guide bush (11) is 10 shown in figure 4. The view A in Figure 4 shows the cutting tool holding slot (9) and wedge slot (10). The cutting tool (13) as shown in figure 6 is accommodated in the cutting tool holding slot (9). The cutting tool (13) is firmly held with the help of grub screws (15) in the threaded holes (5) as shown in Figure 4. 15
[024] Now, referring to Figure 10 showing the operations involved during inserting the tool holder (6) while machining. The guide bush (11) is initially kept in the top position. While inserting the tool holder (6) into the bored hole the center axis of the tool holder (6) and the bored hole is kept with slight offset so that the cutting tool 20 (13) does not interfere with the shell (1). Now the guide bush (11) is slided down and is located to the center of the bored hole.
[025] Figure 11 shows the operations involved during removing the tool holder (6) after completion of machining. The guide bush (11) is slided up first and then the tool holder (6) is brought out in the 25 similar manner as done during insertion. Thus, inside chamfering (4) as shown in Figure 3 is conducted by machining operation instead of grinding and gas-cutting operation using the new tool holder (6).
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[026] Advantageous features of present invention are as follows:-
- Safe
- Does not affect health and environment
- High customer satisfaction
- Facilitates to do subsequent chamfering operation without the 5 need to remove either the cutting tool from the tool holder or the tool holder from the drilling machine spindle by sliding in horizontal and vertical guide ways
- Less time consuming
- Requires less manpower 10
- Less material consumption
- Avoids fatigue at work.
[027] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., 15 bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by 20 those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at 25 least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particulars claim containing such introduced claim recitation to inventions containing only one such recitation, even 30 when the same claim includes the introductory phrases “one or
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more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly 5 recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogues to 10 “at least one of A, B and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and 15 C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be 20 limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or 25 drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B”.
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[028] It is to be noted that the present invention is susceptible to modifications, adaptations and changes by those skilled in the art. Such variant embodiments employing the concepts and features of this invention are intended to be within the scope of the present invention, which is further set forth under the following claims:- 5