AUTOMATIC CHASING MACHINE FOR CTC ROLLER

FIELD OF INVENTION
The embodiments herein generally relate to a CTC roller chasing machine, particularly an automatic chasing machine for CTC roller which can be mechanically and automatically operated without any manual interference.

BACKGROUND OF THE INVENTION
[001] Tea-processing is a four-step process that includes withering, rolling/cutting, oxidation/ fermentation and firing. During the first step i.e. withering, the leaves are spread out until they become limp and pliable. After they become limp and pliable, they are rolled, either by hand, on a rolling table or cut by using a special machine called the CTC (Crushing-Tearing-Curling) roller. When the leaves are rolled/cut, they release chemicals which react with oxygen. This is the third stage which is called oxidation or fermentation. Because of its reaction with oxygen, the leaves take on a reddish-brown tint. After oxidation, the leaves are passed through large ovens, so as to dry the leaves further. This process, called firing is the last step of the four-step process of processing tea.
[002] In the second step of cutting the leaves, the leaves are cut by a special machine called the CTC machine. The machines can crush huge quantities of leaves in short period of time. Moreover, the tea produced by the CTC process, known as CTC tea, is the most popular tea, sharing around 80% of the world market.
[003] The CTC machine includes of a pair of stainless steel rollers with closely meshed circumferential as well as helical grooves. The triple process of crushing, tearing and curling is done by the teeth/grooves of the two rollers which are placed close to one another, and are rotated in opposite directions at a speed differential of about 1:10. The withered tea leaves are fed into the CTC machine and sharp teeth/grooves of the rollers cut and tear the withered leaves and the rubbing action between the flanks of the teeth curl up the leaves. In this way, crushing, tearing and curling of the leaves are done to produce CTC tea.
[004] For CTC processing, the shape and size and accuracy of the teeth/grooves of the CTC rollers are of vital importance to the quality of CTC tea produced. Incorrect maceration would lead to poor quality of CTC tea. The teeth of the rollers are a combination of circumferential and helical grooves uniformly spaced and meshed on the rollers. These grooves are machined on the rollers with the help of special machines. For the circumferential grooving on the rollers, a chasing lathe/machine is used which comprises of a chaser tool that makes the grooves. For the helical grooves, a milling machine is used.
[005] For the chasing operation, a chasing lathe comprises of a chaser, headstock chuck and tailstock. This machine forms the circumferential grooves. Circumferential grooves must be perpendicular to the axis of the roller and must be uniformly spaced. Depending on the user, the grooves can have a V or a U profile. Different profiles are obtained by using different chaser. Chasing operation on a roller requires forming a number of annular concentric grooves. Each inch can have around 8-10 grooves. After the chaser tool completes one grooving operation, it moves axially by manual turning of an indexing wheel until the entire roller is uniformly grooved. At present, the chasing operation is done manually and requires a skilled lathe operator to form grooves which are accurately spaced and accurate in depth. The lathe operator takes reference from the previously chased grooves and makes further grooves. Therefore, this method of chasing depends mostly on the skill of the operator and it might not be satisfactory as it is prone to human errors.
[006] Though the choice of profiles plays a small part in the quality of tea, use of a U-profile allow some particles to escape during maceration. Since, V-profile leads to improved maceration; it is preferred over U-profile.
[007] Accurate advance of the chaser tool is the most important aspect of the chasing operation. This is because incorrect spacing of the circumferential groove will lead to improper meshing of the two rollers. This will, in turn, result in friction between the grooves. The friction of the grooves of the rollers would require more power for the rollers to operate; the grooves of the rollers would be subjected to quick wear and tear resulting in frequent re-sharpening of the edges or replacement of the rollers resulting in capital loss. Most importantly, inaccurate meshing would result in improper cutting of the tea leaves resulting in poorer quality of CTC tea.
[008] To minimize human error in judging the accurate space between concentric grooves, chasing lathe with a digital readout scale is available that helps maintain the accuracy levels. However, even with a digital read-out scale, the process requires manual operation and a skilled operator and therefore, is not fully error-proof. Moreover, an operator needs to be always present to inspect the chasing operation. This is a waste of labor resource.
[009] To form helical and circumferential grooves accurately without any human error, an automatic machine for chasing and milling is described in Indian Patent Application No. 394/DEL/2006. The cited patent application discloses a machines comprises of a servo drive assembly which rotates the CTC roller and also rotates the main lead screw for intermittent movement of the saddle while chasing, thereby providing slow advancing movement while chasing. In addition, to other features, the machine comprises electro-magnetic clutches, power drive arrangements, stepper motor, proximity switches, and electronic control unit having programmable logic controller (PLC). The IN394/CHE/2006 patent application, though efficient in chasing accurately, becomes expensive due to the various components involved in setting up the machine.
[0010] Therefore, there is a need in the art to provide a chasing machine which can be mechanically operated without any manual labor or inspection and which not only provides precise chasing for V-profile or U-profile chasing but also be inexpensive to install. Such a machine should ensure the proper crushing of the tea leaves and improve the quality of CTC tea.
OBJECTS OF THE INVENTION
[0011] A main object of the present invention is to provide for an automatic chasing machine for CTC roller that can be automatically operated.
[0012] Another object of the present invention is to provide for an automatic chasing machine that would accurately and precisely cut the circumferential grooves on the CTC roller.
[0013] Yet another object of the present invention is to eliminate the human errors previously present in the manual chasing operation by making the operation automatic.
[0014] Still another object of the present invention is to eliminate the need of an operator to check the chasing operation, thus saving labor.
[0015] Another object of the present invention is to provide for an automatic chasing machine which is inexpensive to install.
[0016] Another object of the present invention is to provide a roller which is so precisely chased as to crush and tear the tea leaves properly and produce a better quality CTC tea.
[0017] The other objects and advantages of the present invention will be apparent from the following description when read in conjunction with the accompanying drawings which are incorporated for illustration of preferred embodiments of the present invention and are not intended to limit the scope thereof.

SUMMARY OF THE INVENTION
[0018] In view of the foregoing, an embodiment herein provides for an automatic chasing machine that can cut circumferential gradually on the roller surface with precision and without any manual interference or inspection. According to an embodiment of the present invention, the automatic chasing machine provides a mechanical movement of the chaser with the help of uncomplicated mechanism so that no expensive additions/ installations are required. In an embodiment, the automatic chasing machine includes a main lathe frame with a headstock chuck and a tailstock, a motor to rotate the chuck and tailstock, a roller to place in between the chuck and tailstock, a gear reducing mechanism, a chasing tool post, a chasing tool placed on the post, a lead screw to move the chasing tool post, a rotating rod along the length of the lathe, a chasing cam to control the movement of the chasing tool post for cutting the circumferential grooves in the roller, and a tailstock cam with an actuator to move the chaser from one position to another position.
[0019] In an embodiment of the present invention, a roller is placed on a chasing lathe for cutting circumferential grooves on its surface, and held in between the two chucks for rotating the roller. In an embodiment, the rotation of the chucks is enabled with the help of a motor. Further, the headstock chuck is equipped with a gear, called the chuck gear, which mimics the rotational movement of the chuck. Further, the chuck gear is connected to the reduction gear at the rotating rod. According to an embodiment, a gear reducing mechanism is placed in between the headstock rotor and the rotating rod. This reduction gear mechanism being connected to the rotating rod makes it rotate slower than chuck which in turn makes the rotating rod and the chasing cam mounted on it rotate slowly, according to an embodiment. Therefore, the chasing cam is rotated by rotating the rotating rod and the rotation is enabled with the help of the gear mechanism.
[0020] According to an embodiment, the chasing cam is divided into ‘n’ number of slot on the surface with variable diameter, and mechanically coupled to a disc which is attached to a moveable box. Further the moveable box, unattached to the chasing cam but attached to the disc, has a connecting rod connecting the chasing cam to the chasing tool post via a spring mechanism. In an embodiment, the cam-slot of the lower diameter touches the disc for positioning the chaser away from the roller, and the cam-slot of higher diameters touch the disc for the chaser to cut the roller surface. The gear reduction mechanism enables to move/rotate the chasing cam for a slot distance at one rotation of the roller, according to an embodiment. Therefore, the roller may rotate ‘n’ times for the chaser to cut circumferential grooves in one position of the chaser, as the ‘n’ number of slots is provided in chasing cam.
[0021] Once the circumferential groove is cut on the roller in one setting, the chasing cam and the chasing tool post is axially moved to cut the next circumferential grooves by providing a tailstock cam and an actuator at the tailstock part of the lathe, according to an embodiment. The actuator is connected to the tailstock cam via an actuating rod. The chasing cam and tailstock cam are coupled with the rotating rod and are synchronized to rotate each other. At the moment, the lowest diameter of the chasing cam touches the disc, the actuating rod gets inserted in the non-uniform diametric gap of the tailstock cam. At this position, the actuator is actuated to rotate the lead screw on which the chasing tool post is mounted thus moving the tool post, as well as the chasing cam connected to it, to the next position to cut the next circumferential groove on roller. Further, the tailstock cam does not enable the actuator to rotate the lead screw at the time of cutting circumferential groove on roller. The process of cutting the roller surface is followed from the headstock end of the roller to the tailstock end to achieve uniform circumferential grooves gradually on the roller without any manual interference.
[0022] These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The detailed description is set forth with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The use of the same reference numbers in different figures indicates similar or identical items.
[0024] Fig 1 illustrates general view of a chasing lathe according to an embodiment of the present invention.
[0025] Fig 2 illustrates a sectional view of the chasing lathe with a chasing cam along with a chasing tool post according to an embodiment of the present invention.
[0026] Fig 2A illustrates side view of a chasing cam of variable diameter according to an embodiment of the present invention.
[0027] Fig 2B illustrates the cross sectional view of the hollow chasing cam of variable diameter according to an embodiment of the present invention.
[0028] Fig 3 illustrates side view of a chasing lathe along with a tailstock cam and actuator according to an embodiment of the present invention.
[0029] Fig 4 illustrates perspective view of a chasing lathe along with a gear mechanism present at the headstock of the lathe and other parts of the lathe, according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein
[0031] As mentioned above, there remains a need in the art to provide for a chasing machine [also referred as lathe] which would eliminate human error by providing precise chasing on the CTC roller. The embodiments herein achieve this by providing a chasing tool with a chasing cam which operates mechanically and cuts grooves with precision. Referring now to the drawings, and more particularly to FIGS. 1 through 4, where similar reference characters denote corresponding features consistently throughout the figures, preferred embodiments are shown herein.
[0032] Fig. 1 illustrates a general view 100 illustrating different parts of the chasing lathe along with the roller, according to an embodiment of the present invention. Accordingly, the chasing lathe includes a headstock 101 and a tailstock 102 on the main frame 103 of the lathe. Further, on this main frame 103, a roller 104 is placed and held in position with the help of the chuck and tailstock on either end of the roller 104, namely the headstock chuck 105 and the tailstock 106. These chuck and tailstock 105, 106 not only help in the proper placement of the roller 104 on the main frame 103 but also help in rotating the roller 104 when the chasing operation is in progress. The chasing operation is performed by a chaser 107 [also referred as chasing tool] which is placed inside a chasing tool post 108, according to an embodiment. This chaser 107 is equipped either with a U or a V profile so that it can make grooves of a corresponding profile on the roller 104. This tool-post 108 can be moved axially along the axis of the roller 104 with the help of a lead screw 109, according to an embodiment. After engraving of each circumferential groove or set of grooves, the lead screw 109 enables to move the tool post 108 axially towards tailstock so that the next groove/set of grooves can be engraved on the roller 104. In conventional chasing lathe, a person needs to manually check the precise position of the chaser 107 so that the circumferential grooves are uniformly spaced. In an embodiment of the present invention, mechanical cams are provided to engrave the grooves as well as to determine the next accurate position to be engraved. Accordingly, two cams are placed on a rotating rod 111, a chasing cam 110 that moves linearly on the rotating rod 111 and a tailstock cam 113 placed near the tailstock 102. In an embodiment, the chasing cam 110 is placed opposite to the tool-post 108 such that the cam 110 and the tool-post 108 move simultaneously to the next precise position for engraving the groove. This chasing cam 110 can move linearly along the rotating rod 111 which rotates and moves the cam placed on it. To control the rotational movement of the rotating rod 111, a headstock rotor 112 equipped with a gear mechanism 114 is provided. To move the tool post 108 and chaser 107 axially, the tailstock cam 113 is equipped with an actuator 115 connected with the cam 113 via an actuating rod 126, the headstock rotor 112 being placed near the headstock side and the tailstock cam 113 placed near the tailstock side. The mechanical movements of these cams would be described in detail in the following paragraphs.
[0033] The sectional view of the chasing cam 110 along with the chasing tool-post 108 is shown in Fig 2, according to an embodiment. The perspective view of the cam 110 is further shown in Fig 2a and the cross section view of the cam 110 is shown in Fig 2b. As aforementioned, the chasing tool 108 is provided for enabling to engrave proper grooves on the roller surface. In an embodiment, a cam assembly 110A is provided, which comprises of a hollow cylindrical cam 110 and a disc 116 enclosed in a moveable box 117. The disc 116 is attached to the wall of the moveable box 117 but the cam 110 is not directly attached to the box 117. The cam 110 is in touch with the disc 116 solely. The moveable box 117 connected to the disc 116 is further connected to a spring mechanism 118 of a connecting rod 119 on which the chasing tool post 108 is placed. The chasing cam 110 is a hollow cylinder with differential diameter, as shown in Fig 2a and Fig 2b. This hollow cylinder with differential diameter can be achieved by providing a ring of variable diameter 120 around the hollow cylindrical body of the cam 110, according to an embodiment. To provide the ring 120 a variable diameter, the ring is divided into a number of slots 121, each slot of the ring 120 successively increasing in diameter as it progresses to the next slot, as further illustrated in Fig 2b, which shows the perspective view of the hollow cylinder body with the ring of variable diameter 120 provided around it. As seen, the ring 120 has a number of slots 121, successively increasing in diameter, thus achieving a ring with variable diameter 120. This ring 120 when provided around the hollow cylinder 122, a hollow cylinder with variable diameter is achieved. The hollow of this cylindrical cam 110 is mechanically coupled with the rotating rod 111 and inserted as shown in Fig 1.
[0034] Now, referring back to Fig 2, the arrangement of the chasing cam 110 with the chasing tool-post 108 is further elaborated. In accordance with an embodiment, the slotted cam 110 is connected to the disc 116 of the moveable box 117 which is in turn connected to the chasing tool post 108 with the help of a connecting rod 119. This connecting rod 119 includes a sleeve 123 equipped with a spring mechanism 118. As and when the chasing cam 110 rotates and the slot with the smallest diameter 124 touches the disc 116, the moveable box 117 connected to the disc 116 activates the spring mechanism 118 and the tool-post 108 moves thereby retracting the chaser 107 from the roller 104. The reverse action takes place when the slot with the highest diameters 125 [starting from 125a to 125b] touches the disc 116; the chaser 107 moves towards the roller 104 and cuts its surface.
[0035] As aforementioned, the rotating rod 111 passes through the hollow of the chasing cam 110 and connects the headstock rotor 112 at the headstock 101 at one end and the tailstock cam 113 at the tailstock 102 at the other end of the lathe. The tailstock cam 113 of the present embodiment is illustrated in Fig 3. The tailstock cam 113 is in the shape of a disc with a hollow centre through which the rotating rod 111 is connected. This cam 113 is of uniform diameter except at a diametrical gap 127 having lower diameter where the actuating rod 126 can be inserted, thereby connecting and activating the actuator 115. Once the actuator is actuated, the actuator 115 can rotate the lead screw 109 thereby it moves the chasing tool post 108 mounted on the lead screw 109. When one circumferential groove on the roller 104 is cut, both the chasing cam 110 and the tool post 108 are moved to the next position by the rotation of lead screw 109 to cut the next circumferential groove on the roller 104. The rotation movement of lead screw 109 is actuated by the actuator 115 of the tailstock cam 113. Since the same rotating rod 111 connects the chasing tool cam 110 and the tailstock cam 113, both the cam 111, 113 rotate at the same speed. The tailstock cam 113 is positioned such that when one rotation of the chasing cam 110 is completed, the actuating rod 126 moves into the diametrical gap 127 of the tailstock cam 113 thus activating the actuator 115 which is connected to the lead screw 109. Therefore, the lead screw 109 rotates and moves the chasing tool-post 108 placed on it by a specified distance. Along with the tool post 108, the chasing cam 110 also moves the same distance as it is connected to the tool post 108 by the connecting rod 119. Accordingly, the tailstock cam 113 enables to move the chasing tool post 108 by the same distance as the chasing cam 110.
[0036] For the rotational movement of the roller 104, as seen from Fig 4, the roller 104 is connected to the headstock chuck 105 which rotates with the help of a motor 128 and a gear reduction mechanism 129 placed at the headstock rotor 112. The motor 128 rotates the chuck 105, thus rotating the roller 104. In an embodiment, the chasing tool post 108 connected with the chasing cam 110 is such that for the forming of circumferential groove on the roller 104, the roller 104 is rotated at ‘n’ number of times whereas the cam 110 is provided with ‘n’ number of slots to rotate at 1/n times for one rotation of roller 104. In turn, therefore, the rotating rod 111 is rotated slower than the rotational movement of the roller 104. In an embodiment, the gear reduction mechanism enables to reduce the speed to 1/n times of headstock rotor 112. This gear reduction mechanism 129 is connected to the headstock rotor 112. The headstock rotor 112 is further connected to the rotating rod 111. Therefore, because of the slow rotational movement of the headstock rotor 112, the rotating rod 111 moves at a 1/‘n’ rate, this in turn makes the chasing cam 110 on the rotating rod 111 move at a 1/‘n’ rate.
[0037] Operation of the chasing cam: As described in detail in the preceding paragraphs, the chasing cam assembly 110A includes a cam 110 of varying diameter and a disc 116 which is attached to the movable box 117, according to an embodiment. The box 117 is connected with the connecting rod 119 which connects the cam assembly 110A to the chasing tool post 108. Further, the gearing mechanism 129 rotates the headstock rotor 112 and in turn rotates the chasing cam 110 by rotating the rotating rod 111. The cam 110 is provided with n number of slots in the surface of the cam 110, each varying in diameter and the cam 110 is rotated such that the cam slot with the highest diameter 125 touches the disc 116, the box 117 can start to move forward. This forward movement of the box 117 of the connecting rod 119 in turn makes the chasing tool-post 108 placed on the connecting rod 119 move forward, thus engaging the chaser 107 to the roller 104 and making the chaser 107 to cut the roller surface. The diameter variance in the cam 110 can be configured to achieve the desired grooving depth inside the roller, according to an embodiment. Therefore, the forward movement is moved at a distance equivalent to the desired depth of the groove in roller. As the slots 121 of the chasing cam rotate, due to its varying diameter, the disc 116 experiences varying pressures and thus move the box 117 forward which in turn moves the chaser 107 and makes it cut the roller surface at a desired rate. Again, when the cam-slots of the lowest diameter 124 touches the disc 116, the spring mechanism 118 is least tensioned thereby, the chaser 107 can retract from the roller 104. Therefore, as the cam slots changes it position, the spring mechanism 118 can change its tension based on the position box 117. At one cam slot movement/rotation, the entire roller 104 is rotated once. Therefore, if by way of an example, a cam 110 provided with 20 slots, then for each of movement of slots, the roller 104 would move once, starting from the slot with the lowest diameter 124 to the slot with the highest diameter 125. From this movement of the roller 104 and the cam 110, it is evident that for one rotation of the cam 110, the roller 104 would rotate 20 times in order to cut a circumferential groove in one position on the roller surface.
[0038] Operation of the tailstock cam: As described hereinbefore, the tailstock cam 113 is situated at tailstock part 102 of the lathe. In an embodiment, the cam 113 is placed at the end of the rotating rod 111 and it rotates at the same rate as the chasing cam 110. This tailstock cam 113 is connected to an actuator 115 by an actuating rod 126. The actuator 115 is in turn connected to the lead screw 109 on which the chasing tool post 108 is mounted. The actuator 115 helps in rotating the lead screw 109 thereby moving the chasing tool post 108. The tailstock cam 113 has uniform diameter except in a diametrical gap 127 wherein the actuating rod 126 connects the actuator 115 to the cam 113 by placing the actuating rod 126 in the diametrical gap 127 provided in the cam’s diameter. This actuation happens when the lowest diameter 124 of the chasing cam 110 touches the disc 116 of the moveable box 117, i.e. the chasing cam 110 completes one rotation. At this position of the chasing cam 110, the tailstock cam’s position is such that the actuating rod 126 of the actuator 115 is placed in the diametrical gap 127 provided in the cam’s diameter. This activates the actuator 115 which rotates the lead screw 109, thus making the chasing tool post 108 move a certain distance on the lead screw 109. Since the chasing tool post 108 and the chasing cam 110 is connected through the connecting rod 119, both moves the same distance in the same direction.
[0039] Operation of the headstock rotor: The headstock rotor 112 is located at one end of the rotating rod 111 and is equipped with a gear reducing mechanism 129 and gear 130 for the same. The gear 130 of the headstock rotor 112 is connected to the gear 131 of the headstock chuck 105. The rotation of the roller 104 is activated by the rotation of the chucks at its end. The rotation of the chucks is activated by a motor 128 placed at the headstock 101. When the chuck 105 rotates with the help of the motor 128, the gear 131 at the headstock chuck 105 also rotates. This chuck gear 131 in turn rotates the headstock gear 130 at the same speed of rotation. Since a speed difference needs to be maintained between the roller 104 and the chasing cam 110, a gear-reducing mechanism 129 is provided for the headstock gear 130 and the chuck gear 131 to reduce the rotational speed of the rotating rod 111. The gear-reducing mechanism 129 is configured according to the number of slots 121 provided in chasing cam 110. In the chasing cam 110 provided with n slots, for each slot of the cam, the roller 104 will rotate once. In other words, for each rotation of the roller 104, the cam 110 has to rotate 1/n-th distance. For this reason, the gear-reducing mechanism 129 is provided along with the headstock gear 130 and the chuck gear 131. The rotation of headstock gear 130 enables to rotate the headstock rotor 112 which in turn rotates the rotating rod 111. This rotation of the rotating rod 111 moves the chasing cam 110 mounted on it.
[0040] Operation of the Chasing Machine System: A roller 104 is placed on a chasing lathe 100 to cut/chase circumferential grooves on its surface. On both ends of the roller 104, there are chucks 105, 106 that help in positioning the roller 104 properly and more importantly, rotating the roller 104 when the chasing operation is in progress. There may be limit switches [not shown] provided at below the chasing tool post to enable to start and stop the operation process. The rotation of the chucks 105, 106 is controlled by the motor 128 in the headstock 101. The headstock 101 is also equipped with a gear 131 that mimics the rotational movement of the chuck 105. This chuck gear 131 is connected to the headstock gear 130 at the headstock rotor 112. As the rotational speed of the roller 104 is made faster than the cam slot 110 rotation, the one entire rotation of the roller 104 corresponds to the rotational distance of one slot 121 of the cam 110, a gear reducing mechanism 129 is provided along with the chuck gear 131 and the headstock gear 130. This in turn reduces the rotational speed of the headstock gear 130. The cam gear 130 is connected to the headstock rotor 112 which in turn is connected to the rotating rod 111. A headstock rotor 112 at the headstock 101, a tailstock cam 113 on the tailstock 102 and a chasing cam 110 that is moveable on the rotating rod 111. The chasing cam 110 is rotated by rotating the rotating rod 111 and the rotation is provided by the headstock rotor 112.
[0041] The rotation of the rotating rod 111enables the slots 121 of the chasing cam 110 rotate along with it. The slots 121 of the chasing cam 110 has variable diameter and the chasing cam 110 is mechanically coupled with a disc 116 which is attached to a moveable box 117. This moveable box 117, unattached to the chasing cam 110 but attached to the disc 116, has a connecting rod 119 that connects the chasing tool post 108 via a spring mechanism 118. During the cam slot of the lowest diameter 124 touches the disc 116, the spring mechanism 118 is least tensioned and the chaser 107 does not cut the surface of the roller 104. During the cam slot of higher diameter touches the disc 116, the spring mechanism 118 experiences variable tension that leads the chaser 107 to cut a single circumferential groove with varying pressure. At one particular slot 121 movement of the chasing cam 110, the roller 104 rotates once. Therefore, if there is n number of grooves on the chasing cam 110, the roller 104 would rotate n times for the chaser 107 to cut one circumferential groove.
[0042] Once the circumferential groove is cut on the roller surface, both the chasing cam 110 and the chasing tool post 108 is moved to a certain distance to cut the next one or few circumferential grooves. The distance of the movement is determined based on the width covered by chasing tool post. To aid this movement, the tailstock cam 113 and actuator 115 is provided at the tailstock part 102 of the lathe 100. The tailstock cam 113 is a disc with a hollow centre wherein the rotating rod 111 is connected and is of a uniform diameter except at diametrical gap 127. The actuator 115 is connected to the tailstock cam 113 via an actuating rod 126. The non-uniform diametric gap 127 of the tailstock cam 113 diameter is placed such that when the lowest diameter 124 of the chasing cam 110 touches the disc 116, the non-uniform diametric gap 127 of the tailstock cam 113 touches the actuating rod 126. As mentioned hereinbefore, all the cams move at the same speed. When the chasing cam 110 completes one rotation of its slots and comes back to its lowest diameter 124, the actuating rod 126 gets inserted in the non-uniform diametric gap 127 of the tailstock cam 113. This position actuates the actuator 115 and the actuator 115 rotates the lead screw 109 on which the chasing tool post 108 is mounted, thus moving the tool post 108 by a certain specified distance. Again, since the chasing tool post 108 is connected to the chasing cam 110 by the connecting rod 119, therefore, as the chasing tool post 108 is moved along the lead screw 109, the chasing cam 110 also moves that same distance on the rotating rod 111. According, the chasing cam 110 and the tool post 108 moves to the next position to cut the next circumferential groove on the roller surface; the entire operation of cutting the roller surface is repeated again till the end of tailstock. This cutting operation continues from the headstock 101 end of the roller 104 to the tailstock end 102, and it’s starting and ending position is adjusted with the help of limit switches [not shown] provided below the tool post.
[0043] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

I Claim:
1. An automatic chasing machine for cutting circumferential grooves on a CTC roller, wherein the machine comprises of
a headstock chuck and a tailstock for placing the CTC roller;
a motor to rotate the chucks;
a rotating rod along the length of the lathe;
a gear reducing mechanism for rotating the rotating rod;
a chasing tool for cutting circumferential grooves on the rollder;
a chasing tool post for moving the chasing tool;
a lead screw for placing the chasing tool post by that; and
a chasing cam for controlling the movement of the chasing tool post for cutting the circumferential grooves in the roller.
2. The automatic chasing machine of claim 1, further comprises of a tailstock cam with an actuator for enabling to move the chaser from one position to another position.
3. The automatic chasing machine of claim 2, wherein said chasing cam is provided with ‘n’ number of slots having variable diameters.
4. The automatic chasing machine of claim 3, wherein said chasing cam and said tailstock cam are mechanically coupled to said rotating rod.
5. The automatic chasing machine of claim 3, wherein said rotating rod is rotated with the help of gear reducing mechanism for rotating the chasing cam and tailstock cam.
6. The automatic chasing machine of claim 3, wherein said gear reducing mechanism is connected to chuck gear for rotating said rotating rod, wherein said chuck gear is connected to the said chuck.
7. The automatic chasing machine of claim 3, wherein said rotation of rotating rod rotates said chasing cam and said tailstock cam at the same speed.
8. The automatic chasing machine of claim 3, further comprises of a cam assembly, wherein said cam assembly comprises of said chasing cam, a disc, and a moveable box.
9. The automatic chasing machine of claim 8, wherein said chasing cam is mechanically coupled to said disc, wherein said disc is attached to said moveable box.
10. The automatic chasing machine of claim 9, wherein said moveable box is connected to said chasing tool post via a connecting rod and a spring mechanism.
11. The automatic chasing machine of claim 10, wherein rotation of said chasing cam enables to move said moveable box and said chasing tool post in forward and backward direction, wherein said moveable box connected to said chasing tool post via said connecting rod.
12. The automatic chasing machine of claim 11, wherein said movement of chasing tool post enables to cut circumferential grooves gradually on said roller by using said chasing tool.
13. The automatic chasing machine of claim 12, wherein said tailstock cam enables to actuate an actuator placed on said lead screw at the tailstock end through an actuating rod.
14. The automatic chasing machine of claim 13, wherein said tailstock cam has diametrical gap of lower diameter, wherein said diametrical gap is provided at the position parallel to the lower diameter of said chasing cam.
15. The automatic chasing machine of claim 14, wherein said lower diameter slot of said chasing cam touches said disc thereby making said chasing tool post retract from said roller.
16. The automatic chasing machine of claim 14, wherein said higher diameters slot of said chasing cam touches said disc thereby making said chasing tool post to move forward towards roller for cutting circumferential grooves gradually.
17. The automatic chasing machine of claim 14, wherein said lower diameter slot of chasing cam touches said disc to move said chasing tool post retract from said roller, and in parallel said lower diameter diametrical gap allows to actuate said actuator through said actuating rod thereby enabling rotation of lead screw during the moment.
18. The automatic chasing machine of claim 17, wherein said rotation of lead screw enables to move said chasing tool post and said chasing cam from one position to another position.
19. The automatic chasing machine of claim 17, wherein said movement of chasing tool post occurs at the time of said chasing tool post is kept away from said roller.
20. The automatic chasing machine of claim 17, wherein said variable diameter of chasing cam is configured to move said chasing tool post at the desired distance, wherein said distance is determined based on the required depth of groove on the roller.