GB2210767A - A crushing/cutting, tearing and curling machine - Google Patents

Abstract

A C.T.C. machine for processing of tea leaves and having a meshing pair of serrated rollers 20, 30, caused to be rotated in opposite direction to each other is characterised in that one of the said rollers (30, Fig. 2) is journalled at its both ends in a pair of bearing assemblies, which are slidable in relation to the machine frame in the radial direction of the rollers, and one of the said bearing assemblies is also slidable in relation to the machine frame in the axial direction of the rollers, or one of the said rollers (20, Fig. 1) is journalled at its one end in a bearing assembly which is slidable in relation to the machine frame in the axial direction of the rollers, that said bearing assembly(ies) is (are) held against one or more spring(s), and that means are provided for sliding the said bearing assembly(ies) against the tension of the said spring(s) for causing axial and/or radial movement of one roller in relation to the other roller. <IMAGE>

Description

A crushing/cutting, tearing and curling machine The present invention relates to an improved C.T.C. machine, and, in particular, the invention is concerned with the roller systems of such machine used in tea processing industry.

C.T.C. machine is widely known in the tea industry meant for crushing/cutting, tearing and curl in of pre-processed tea leaves. The expression 'C.T.C.' used troughout the specification stands for the abbreviated form of crushing/cutting, tearing and curling. The C.T.C. machine has a meshing pair of serrated rollers, which are caused to be rotated in opposite direction to each other and one rotates at much richer sued relative to the other. The rollers are provided surfaces ther@of with segments, preferably of stainless steel, and tht- outer surface of said segments are properly milled and groove to provided dents and ridges.The leaves, to be processed, are passed through a predetermined gap maintained between the said groove surfaces of the rollers. A conveyor assembly is provided b means of which the tea leaves, to be processed, are carried onto the rollers. The machine is also generally provided with conveyor rollers, magnet assembly for removing foreign iron FarticleE from the tea leaves, spreader assembly for spreading the tea leaves onto the conveyor and usual drive arrangement.The slow speed and high speed rollers are driven by gear box and the relative speed ratio between the said rollers is governed by the geal ratic of thee said gear box, The drive arrangement with disengagement clutch system is provided through individual motor or from 2 line shaft.

In C.T.-C. machines, the meshing gair of serrated rollers need to be adjusted both axially and radially. Such adjustment of C.T.C. rollers is done manually by adjustin:; the studs and nuts or by worm wheel and screw arrangements. Various methods of radial and axial adjustment of C.T.C. rollers are known in the art. None of these conventional methods are free fr defects or can be operated without much skill.

The purpose of axial arrangement of tL'e rt rs in C.T.C.

machines is to match the mesl,ing of tE grooves in such rollers while the rollers need to be adjusted radially in C.T.C.

machines for controlling the gap between suc rollers to achieve the desired "cut" of tea leaves. When the two rollers are adjusted so as to have very little space in between, finer grade of tea leaves can be obtained. Conversely, for a bigger gap or space between the rollers, coarser variet or grade of tea leaves can be expected.

The axial adjustment of the rollers in the C.T C. machine is achieved by moving either or both the r ll;rs axially through the bearing which is locked on to b)e roller at one or both the ends thereof. In the above machine, the bearing housing is to be moved and such a movement or adjustment is done by mean of two covers and the use- of studs and nuts.

The radial adjustment of the rollers in C.T.C. machines, after their initial setting, is necessary mainly for the following reasons : a) Jamming of the machine due to foreign matters agglomerating between the rollers ; b) Over-feeding of tea leaves causing sudden stoppage of the C.T.C. machine ; and c) The sudden failure of power supply which. has the same effect as in (b) above.

In all the above three cases, the rollers should be moved apart, the cause of the jamming shouln be removed and the rollers should be re-ad justed before restart n the machine, The purpose of bringing apart the rollers is t relieve the load between the rollers for easier re-starting of te machine and/or removing any embedded foreign matter in the rollers.

When the rollers are overloaded or a hard foreign matter gets, between them any, or a combination of to:e following occurs : i) Machine jams (rollers cease to rotate) ; ii) Motor, if the starter fails to trip, ceases and burns out ; iii) Any other part of the machine, tt bears the brunt of the shock, breaks.

The following disadvantages have been experienced in the conventional methods of adjustment of rollers in a C.T.C. machine - a) check nuts must be adapted in te roller system of C.T.C. machine to prevent undesirable movement or displacement of the bearings when the machine is in operation ; b) at least four parts including check nuts need to be adjusted to adjust the rollers ; c) high degree of skill is required to operate the adjustment of rollers ; and d) the displacement or adjustment of rcllers is quite often not satisfactory as it needs high degree of skill for the operator.

When the axial movement of the rollers Is adjusted by means of studs and nuts at least ten parts need to be operated or manipulated. Further, the accuracy of sucr adjustment is subjected to the personal error of the operator.

According to the conventional methods, te two bearings* which are located at one or both ends of tre rollers* are adjusted.

The radial adjustment of the rollers can be done either by screw mechanism or by means of worm'wheel and scrow rrengement.

For the movement of any one of the rollers towards or away from each other, a screw mechanism for displacing individual bearing housings may be adopted while simultaneous adjustment of both ends of a roller is done by means of a worm and worm wheel arrangement. According to this arrangement both ends of a roller are operated simultaneously by a worm wheel over each nut and by operating the worm wheel by two worms on a common shaft.

The ad3ustment of rollers can also be done by what is known as sprocket screw mechanism according to which nuts are rotated simultaneously by sprockets (over each nut) and chain to connect both of them, so that by rotating one roller the other can also be rotated.

In the case of restarting the machine after jamming in the conventional methods, the rollers are moved apart, thc cause of te jamming is cleared manually and te rollers are adjusted by rotating them in the reverse direction before starting the motor for the machine. This process of adjustment or readjustment of rollers is not only tie consuming, such an operation requires most careful attention and skill of the operator.

It is, therefore, an object of the per sent invention to mitigate the drawbacks which have been experienced in the conventional methods of adjustment of the- rollers in the C.T.C.

machines either axially or radially.

Another object of the present invention is to provide a C.T.C.

iac'hie having an improved roller system for an easy operation thereof.

A further object of the present invention is to reduce the number of moving parts in tile roller systems and thereby making the operation of the machine or the adjustment of the rollers less cumbersome.

A still further object of this invention is to cause automatic radial displacement of one roller away from t other roller and thereby to ' increase radial gap between tne two rollers in the event of jamming of the said two rollers caused by overloading of the rollers with excess tea leaves and/or by intrusion of hard foreign material into the ga between the rollers or for any other reason.

The improved C.T.C. machine of the present invention avoids the use of a number of moving components which were considered necessary in a known machine and it has dispensed with check nuts and grab screws. This is possible as the bearing movement or adjustment thereof is monitored and controlled by the tension of one or more spring(s). The operation of the improved C.T.C.

machine having such improved bearing assembly (ies) for its rollers, therefore, needs little or no skil t all.

Accordingly, the present invention provides an improved C.T.C.

machine for processing of tea leaves, havin 2 mest.inffl pair of serrated rollers, caused to be rotated in opposite direction to each other, characterised in th-t one of t- said rollers is journalled at its both ends in a pair of bearing assemblies, which are slidable in relation to the machine frame in the radial direction of the rollers, and one of the saic bearing assemblies is slidable in relation to the machine frame An the axial direction of the rollers, or one of the said rollers is journalled at its one end in a bearing assembly which is slidable in relation to the machine frame in the axial direction of the rollers, that said bearing assembly (ies) is (are) held against one or more spring(s), and that means are provided for sliding the said bearing assembly (ies) against the tension of the said spring(s) for causing axial and/or radial movement of one roller in relation to the other roller.

In a preferred embodiment, said axially slidable bearing assembly is constituted by a bearing accommodated within a housing and held between a threaded outer cover and an inner plate which is loaded by the said spring(s), said spring(s) being adapted to hold said inner plate against the bearing which is in abutment with the stid roller, the arrangement being suc tt on turning of the said threaded outer cover in relation to the not" sing the said roller is caused to be moved axially in relay ore to the other roller.

Said housing is designed for a smooth and interference free sliding fit. Said spring(s) is(are) of any suitable size and adapted to hold the inner plate against the bearing. The said roller and the said bearing are securely fixed to each other.

In another preferred embodiment, the said radially slidable bearing assemblies comprise a pair of housings accommodating the respective bearings, each said housing being slidably mounted on a pair of side plates and held between a pair of springs at onc end and an eccentric sleeve located at the other end of said housing. The said eccentric sleeve may be replaced by a cam shaft which is adapted to be operated by a lever, or by a motor controlled either manually or electrically, or by an electronic device.

For causing automatic radial displacement of the spring-loaded roller away from the other roller and thereby to increase radial gap between the two rollers, the cam shaft has securely provided at its one end with a spring lever such that in te horizontal disposition of the said spring lever the cams of the cam shaft are adapted to be engaged with the said housings of the said bering assemblies at the maximum cam profile, while on angular movement of the sprkng lever from its horizontal disposition the cams are adapted to be angular moved for allowing displacement of the springloaded roller journalled in the said bearing assemblies, away from the other roller, and the free end of the said spring lever is adapted to be latched onto the machine frame in the horizontal disposition of the lever such tI:at in the event of jamming of the said two rollers caused by overloading of the rollers with excess tea leaves and/or by intrusion of hard foreign material into t;e gap between the rollers, or for any other.reason, the spring lever is capable of being unlatched to have angular movement and thereby to allow the spring-loaded roller to be displacec automatically away from the other roller.

As a preferred embodiment of the aforementioned arranement, the tension of the spring lever is adapted to be varied depending on the desired load to be imposed in between the two rollers, such that the saidpring lever is capable of being automatically unlatched as and when the load between the two rollers exceeds the desired load.

The tension of the spring lever is capable of being varied by a tension adjusting screw mounted on the spring lever.

In a particular embodiment, the free end of the spring lever is provided with a V' - stopper, which is adapted to be engaged with a corresponding groove provided on the mschine frame for latching of the spring lever and for being maintained in its horizontal disposition.

The nature and scope of the invention will be better understood from the following description, set out by way of illustration, but not'by way of limitation, with reverence to the accompanying drawings, wherein Fig. 1 illustrates the arrangement according to this invention for axial adjustment of the C.T.C.

rollers ; Fig. 2 illustrates the arrangement according to this invention for radial adjustment of such rollers Fig. 3 shows in elevation the salient portions of one embodiment of the improved C.T.C. machine according to the present invention, having the arrangement for automatic radial displacement of one roller in relation to the other Fig. 4 is a plan of the embodiment shown in Fig. 3 ; and Fig. 5 is a fragmentary sectional view of a part of the embodiment, shown in Figs. 3 and 4, taken along the sectional line X-X1 of Fig. 3, With reference to Fig. 1, for the axial adjustment of the rollers, the assembly includes a bearing 10 which is accommodated within a housing 12. Such housing is designed for a smooth and interference free sliding fit. The bearing is held sandwiched between a threaded outer cover 15 and a sprin loaded inner plate 18. A spring 19 of appropriate size is adapted to hold the inner plate against the bearing which is in abutment with the roller 20. The turning of the outer cover 15 in the threaded housing causes it to move axially. When the cover is tightened it pushes or displaces the bearings towards the spring, that is, ;ward8 as shown in Fig. 1. On the other hand, when the cover is slackened, the spring loaded plate 19 displaces the bearing 1O away from-it, that is, it imparts an outward movement to the roller. The bearing being securely fixed to the roller 20, it displaces the roller axially away from the spring and thereby desired meshing of the grooves in the rollers is possible.

Unlike the conventional method of adjustment of the rollers, the present system of axial adjustment of C.T.C. rollers is iore accurate. Further, less degree of skill is required for its adjustient.

In Fig. 2 of the drawings, movement of only one roller is shown.

Roller 30 is mounted on a pair of housings 52 which are mounted on a pair of side plates (not shown) but free to slide. The housing is held between a pair of springs 38, 38' at one end thereof and at the other end of the housing, an eccentric sleeve 40 is located.

The movement of the eccentric sleeve causes the housing to move forward or backward as shown and hence the rollers come coster to one another or move apart.

The movement of the rollers, according to the improved -system, is synchronous and simultaneous facilitating fine adjustment for scutn of tea leaves in the C.T.C, machines. The improved system also displaces the rollers away from each other and, therefore, allowing the machine to be restarted without manually releasing the leaf pressure. The eccentric sleeve or cam shaft 41 may be operated by a lever 42 or by a motor controlled either manually or by an electrical or an electronic device to achieve the desired result.

As shown in Figures 3 and 4, two rollers 1 and 2 (partly seen) of the improved C.T.C. machine are in operative engagement with each other. The bearing housings 4 of the roller 1 are slidably mounted on the machine frame in the same manner as described hereinbefore. The housing 4 is held between a pir of springs 5 at one end thereof and at the other end of the housing 4 cam 6 is located. Two such cams are mounted on either end of the camshaft 3 for the bearing housings 4 at either end of the roller 1.A spring lever 7 is securely con':ected to t''jt end of the camshaft 3 such that the camshaft can be move angularly by the angular movement (shown in dotted lines) of' thc spring lever 7.

The angular movement of the cams causes tl-e losinr 4 to move linearly and hence the rollers come closer or further apart to or from each other. The spring lever 7 is connected to the end of the camshaft 3 such that in the horizonta disposition of the spring lever 7, the cams 6 of the camshaft are adapted to be engaged with the housing 4 of the spring-loaded roller 1 at the maximum cam profile indicated by 6A. On angular movement of the spring lever 7 and particularly when it moves down to 900, the cams 6 are also consequentially turned for displacement of the spring-loaded roller 7 away from the other roller 2.The tree end 8 of the spring lever 7 is provided with a latch mechanism, indicated in general by 9, and shown in detail in Fig. 5. As shown in Fig. 5, such latch mechanism comprises a 'V'-stopper ?Od securely provided at the bottom surface of the spring lever 7, which is adapted to be engaged with a corresponding groove 11A provided on the machine frame 12A. The spring lever 7 is held in its horizontal disposition by such latch mechanism, The spring lever 7 is retained in its engaged horizontal position by ffi tension adjusting screw 13A which presses the spring lever for being latched. The said screw 13A can be turned in either direction to increase or decrease the tension of the spring lever.The tendency of the housing 4, due to leaf pressure between the rollers 1 and 2, is to push and turn the cams 6 and spring lever 7 down.

This force is balanced by the tension of trite spring lever so that it remains horizontal under normal cutting load but falls down when excess load is applied between the rollers With the aforementioned arrangement, the spring-loaded roller 1 is adapted to be automatically displaced away from the other roller 2 and thereby to increase the radial gap between the two rollers in the event of jamming of the rollers caused b overloading of the rollers with excess tea leaves and/or b- intrusion of hard foreign material into the gap between the rollers, or for any othcr reason. B- adjusting the tension of the spring lever 7 by means of the screw 13A, the spring lever 7 is capable o beinG unlatched automatically as and when the load between t two rollers 1 and 2 exceeds desired load.

The following advantages over the conventional a-angements have been noticed in the C.T.C. machines havin new roller assembly a) no slack between the mechanism t tbs housing as the shock is taken up by the s rins b) much less mechanical movement gives quicker and more accurate cut of tea leaves ; and c) no back-lash as there are no screws, worm and worm wheel or chain and sprocket, therefore less wear and tear.

It is to be understood that various other modifications and legitimate developments of the improved arrangement of the roller system in C.T.C. machine are possible within the scope of what has been described hereinbefore, and will be claimed hereinafter.

Claims (12)

Claims:

1. An improved C.T.C. machine for processing of tea leaves, having a meshing pair of serrated rollers, caused to be rotated in opposite direction to each other, characterised in that one of the said rollers is journalled at its both ends in a pair of bearing assemblies, which are slidable in relation to the machine frame in the radial direction of the rollers, and one of the said bearing assemblies is also slidable in relation to the machine frame in the axial direction of the rollers, or one of the said rollers is journalled at its one end in a bearing assembly which is slidable in relation to the machine frame in the axial direction of the rollers, that said bearing assembly (ies) is (are) held against one or more spring(s), and that means are provided for sliding te said bearing assembly(te against the tension of the said s ring( s) for causing axial and/or radial movement of one roller in relation to the other roller.

2. An improved C.T.C. machine as claimed in claim 1, wherein said axially slidable bearing assembly is constituted by a bearing accommodated within a housing and held between a threaded outer cover and an inner plate which is loaded by the said spring(s), said spring(s) being adapted to hold said inner plate against the bearing which is in abutment with the said roller, the arrangement being such that on turning of the said threaded outer cover in relation to the housing te said roller is caused to be moved axially in relation to the other roller.

3. An improved C.T.C. machine as claimed in claim wherein said housing is designed for a smooth 'and inter- ference free sliding fit.

An An improved C.T.C. machine as claimed in claim 2 or 3, wherein said spring(s) is(are) of any suitable size and adapted to hold the inner plate against the bearing.

5. An improved C.T.C. machine as claimed in any of claims 2 to 4, wherein the said roller and the said bearing are securely fixed to each other.

6. An improved C.T.C. machine as claimed in claim 1, wherein the said radially slidable bearing assemblies comprise a pair of housings accommodating the respective Jxlxlrg bearings, each said housing being slidably mounted on a pair of side plates and held between a pair of springs at one end and an eccentric sleeve located. at the other end of said housing,

7. An improved C.T.C. machine as claimed in claim 6, wherein said eccentric sleeve is replaced b a cam shaft which is adapted to be operated by a lever, or by a motor controlled either manually or electrically, or by an electronic device.

8. An improved C.T.C. machine, as claimed in claim 7, wherein for causing automatic radial displacevfent of the spring loaded roller away from the other roller and thereby to increase radial gap between the two rollers, the cam shaft has securely provided at its one en; with a spring lever such that in the horizontal disposition of the said spring lever the cams of the camshaft are adapted to be engaged with the said housings of tie bearin; assemblies at the maximum cam profile, while on angular movement of the spring lever from its horizontal disposition the cams are adapted to be angularly moved for allowing displacement of the spring-loaded roller journalled n tr3e said bearing assemblies, away from the othr-r r ller, and the free end of the said spring lever is adapted to be latched onto the machine frame in the horizontal disposition of the lever such that in the event of jamain of the satd two rollers caused by over-loadin" of the rollers with excess tea leaves and/or by@intrusion of @ard foreign material into the gap between the rollers, or for any other reason, the spring lever is capable of being unlatched to have angular movement and thereby to allow the spring-loaded roller to b@ @@@@@@ d automatically away from the other roller.

9. A C.T.C. machine as claimed in claim. 8, wherein the tension of the spring lever is adapted tc be veried 'depending on tIJe desired load to be imposed in between the two rollers, such that the said spring lever is capable of being automatically unlatched as and when the load between the two rollers exceeds the desired load.

10. A C.T.C. machine as claimed in claim 9, wherein the tension of the spring lever is capable of being varied by a tension adjusting screw mounted on te spring lever.

11. A C.T.C. machine as claimed any o claims 8 to 10, wherein the free end of the sprit, lever is provided with a 'V'-stopper, which is edarteç to be engaged with a corresponding groove provided on the machine frame for latching of the spring lever and for being maintained in its horizontal disposition*

12. An improved C.T.C. machine substantia'ly as hereinbefore described with particular reference to, and as illustrated in the accompanying drawings.