GB1597419A

GB1597419A - Manufacture of ceramic ware

Info

Publication number: GB1597419A
Application number: GB2096978A
Authority: GB
Original assignee: Service Engineers Ltd
Current assignee: Service Engineers Ltd
Priority date: 1978-05-20
Filing date: 1978-05-20
Publication date: 1981-09-09
Also published as: DE2920282A1

Description

(54) IMPROVEMENTS IN OR RELATING TO THE MANUFACTURE OF CERAMIC WARE (71) We, SERVICE (ENGINEERS) LIMITED, a British Company of Leek New Road, Cobridge, Stoke on Trent, Staffordshire, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention is concerned with improvements in or relating to the manufacture of ceramic ware, and, more particularly, to the smoothing of cup handles in the clay state to remove seams normally left along their longitudinal planes of symmetry by the moulding operation used in making them.

Seams of cup handles are customarily removed by hand using a trimming tool or other smoothing medium, though mechanical equipment is also available to assist the operation, for example by pushing the handle through a sponge which has a passage through it with a profile similar to, but a little narrower than, the handle. Using such a machine it is necessary to keep the sponges clean, because otherwise they become clogged with the clay removed from the handles. The addition to such a machine of the facility to clean the sponges automatically adds to the expense and complication of the machine.

It is one of the various objects of the present invention to provide an improved method of smoothing cup handles in the clay state.

It is another of the various objects of the present invention to provide an improved cup handle de-seaming machine.

There is hereinafter described in detail to illustrate the invention in its method aspects by way of example a method of removing seams of cup handles in the clay state in which the handle is held between two parts of a holder in such a manner that the seam is exposed at both the inside and outside of the handle, and a rapidly rotating pin of small diameter is caused to traverse the length of the seam. In carrying out this illustrative method, the Din is a smooth cylindrical one, its clay-engaging portion being sufficiently thin to enter crevices, or reentrant portions, of the handle to remove the seam without distorting the profile. A diameter not exceeding 0.45 cm, for example 0.3 cm., has been found satisfactory for a pin with its axis at right angles to the plane of the seam, and rotating at not less than 20,000 r.p.m., even up to, say, 60,000 r.p.m.

The pin presses against the seam in carrying out the illustrative method to an extent limited by engagement of a cam follower with a profiled template on the holder.

In carrying out the illustrative method the clay of the seam is pressed smoothly into the profile of the handle. Removing the seam of the handle is thus achieved by displacing clay without removing clay from the handle altogether, with consequent greater cleanliness than is the case where there is surplus clay removed from the handle to be disposed of.

A de-seaming machine illustrative of the invention in its machine aspects and used in carrying out the illustrative method is also described in detail hereinafter, this illustrative machine having two holders mounted on conveyor means in the form of an arm rotatable about a central vertical axis to bring the holders, which are mounted one on each end of the arm, alternately into an operating position where the pin traverses the seam of a handle held by the holder and a loading and unloading position. Each holder of the illustrative machine is mounted for rotation about a vertical axis on the arm, a handle resting, in the operation of the machine, on a lower clay-engaging part of the holder, and being held there by lowering an upper part onto it to lightly clamp it. The holder parts are so shaped as to leave the seam both on the inside and the outside of the handle exposed.

The illustrative machine also comprises a pin support slidable along a horizontal path radial to the axis of rotation of a holder at the operating position and urged resiliently in such a direction along said path that the pin is constantly urged towards a handle held by the holder in the deseaming operation. Each clay-engaging part of each holder has a profile similar to the handle but is narrower than the handle so as to leave the seam exposed; a cam follower in the form of a roll co-axial with the pin engages a template constituted by a shoulder of one of the holder parts set back from its edge to provide a step wide enough to accommodate a projecting portion of the cam roll. Thus the pin is able to bear on the clay as the holder rotates to cause the pin to traverse the length of the seam.

Electric motors to rotate the holders are switched on and off in the operation of the illustrative machine before and after the smoothing operations, means being provided to ensure that each holder makes one complete revolution in the de-seaming operation.

Hand operated means is provided on each holder of the illustrative machine to enable an operator to open and close the clayengaging parts at the loading and unloading station. Automatic, instead of manual feeding, with automatic opening and closing of the holder parts could alternatively be provided if desired. The clay engaging parts of the holder are readily detachable for replacement by others of suitable shape when handles of different shapes have to be deseamed.

The illustrative machine enables handles to be de-seamed uniformly and reliably without interruption for occasional cleaning of parts which have become clogged or contaminated by surplus clay, because no significant amount of clay is removed from the handles.

In carrying out the illustrative method, a smooth pin of uniform diameter is used with its axis at right angles to the plane of the seam. Pins of other configuration where they engage the clay each and disposed with its axis lying in a plane at right angles to the plane of the seam, but inclined within such plane to the plane of the seam itself, may be selected, if desired The invention provides, in one of its several aspects, a method of removing seams from cup handles in the clay state by causing a rotating pin to traverse the length of the seam, whereby the clay of the seam is pressed smoothly into the profile of the handle.

The invention also provides, in another of its several aspects, a cup handle de-seaming machine comprising a shaped holder by which a cup handle can be held with its seam exposed, a rotary pin, means for rotating the pin, means for causing the pin and a handle held by the holder to be urged into engagement with one another in the operation of the machine, and means for causing movement to take place between the holder and the pin while the pin bears upon the handle in such a manner that the pin traverses the seam and presses the clay smoothly into the profile of the handle.

The above mentioned objects and aspects of the invention will become more clear from the following description, to be read with reference to the accompanying drawings, of the illustrative machine and illustrative method aforementioned. It will be realised that this illustrative machine and the illustrative method have been selected for description by way of example and not of limitation of the invention.

In the accompanying drawings: Figure 1 is a view in elevation and partly in section of an upper part of the illustrative machine; Figure 2 is a diagrammatic plan view of the illustrative machine; and Figure 3 is a view of the upper part of the illustrative machine in section on the line III-III of Figure 1.

The illustrative cup handle de-seaming machine comprises a base (not shown, being below the level of the part of the machine shown in Figure 1) from which a bracket 10 projects upwardly at one end; the base also supports a vertical shaft 12 arranged to rotate step-by-step through 1800 between each step. The shaft 12 carries an arm 14 which is mounted centrally on the shaft and at each end carries a rotatable holder 16, 16'. The two holders 16, 16' are of the same construction. (The one 16 shown on the left in Figure 1 will be described in detail hereinafter, reference to corresponding parts of the holder 16' and of parts of the machine associated with it being suffixed by a dash).Each holder 16, 16' has a lower clay-engaging part 18, 18' detachably secured by bolts 17 to a flange 19, 19' at the top of a vertical shaft 20, 20' rotatably mounted on the arm and arranged to be rotated intermittently by an electric brake motor 22, 22' connected to a pulley 24, 24' on the shaft 20, 20' by a belt 26, 26'. The motors 22, 22' are mounted on rubber bushes 28 on an underside of the arm 14.

The lower clay-engaging part 18 of the holder 16 has an upstanding rib 30 with a shaped portion of corresponding profile to the handle. The upper surface of the rib 30 has a groove 32 in which the handle can rest. The holder 16 also has an upper part 34 of the same outline shape as the rib 30 of the lower part, so that it likewise has a portion of corresponding profile to the handle, but narrower. The upper die part 34 has a groove 36 in its lower surface, complementary to the groove 32.

The illustrative machine is intended for use in de-seaming what are known as "openended" handles, that is to say ones which are subsequently attached to cups at two locations, the ends of the handles being separated by a surface portion of the cup, in contrast to "closed" or "D-shaped" handles, that is to say ones which completely surround a hole into which the user may insert a finger. The grooves 32, 36 are long enough, in the illustrative machine, to accommodate not only the length of handle which comes to be attached to a cup, but also such length of clay (indicated at E on the handle H shown in Figure 2) as usually projects further from each end of the piece at the de-seaming stage of handle making and is subsequently cut off before attaching the handle to the cup.Beyond each end of the grooves 32, 36 of the rib 30 and upper part 34 respectively of the holder 16 are terminal sleeve portions 40 of circular outline. The bores in the sleeve portions 40 of the lower holder part 18 are continued through the flange 19. Vertical shafts 42 are slidable in the sleeve portions of said lower part 18 and in the bores in the flange 19. The upper holder part 34 is detachably mounted on upper end portions of the shafts 42 by transverse taper pins 43. Lower end portions of the two shafts 42 are interconnected by a transverse bar 44 with a horizontal slot 46 in it. Depending from the flange 19 is a boss 48 with a horizontal bore in which a shaft 50 is rotatable, the shaft 50 carrying at one end an eccentric pin 52 accommodated in the slot 46 and at the other a handle 54. By turning the handle 54, the upper holder part 34 can be raised and lowered.The upper part 34 can thus be lowered upon a handle H (Figure 2) resting on the groove 32 to clamp it lightly and hold it in position for the de-seaming operation.

Because the rib 30 and upper die part 34 are narrower than the handle, when the handle is so held, its seam is exposed both on the inside and the outside and projects just beyond the periphery of the parts 30, 34.

In Figure 1, the holder 16 is shown open (i.e. with the upper part 34 raised) at a loading and unloading position of the illustrative machine and with its motor switched off; the holder 16' is shown at the operating station of the illustrative machine, rotating on the shaft 20'.

Projecting from the bracket 10 (Figure 1) of the illustrative machine and towards the axis of rotation of the shaft 12 are two horizontal cylindrical guides 60, 60', one above the other. The guides 60, 60' are slidable in bores at the upper end of the bracket 10 and connected together at their right hand ends (shown in Figure 1) to the right of the bracket by a plate 62, an upper end of which is secured to a piston rod of a pneumatic cylinder 64. The guides are also connected together at their left hand end by a plate 66. Slidable on the guides 60, 60' is a carriage 68 which includes an air motor (not shown) having a vertical output shaft 70 to which a smooth cylindrical pin 72 of uniform diameter 0.3 cm. is fixed, the pin pointing downwardly far enough to engage the seam of a cup handle in the holder 16' at the operating position.The carriage 68 is constantly urged to the left (shown in Figure 1) by a band 74 secured to the carriage; the band passes round a pulley 76 rotatable on the plate 66 and is secured to a reel 78 which is urged constantly anticlockwise (viewing Figure 1), The limit of movement of the carriage to the left, however, is determined by a cam roll 80 mounted on the shaft 70 at the top of the pin 72 engaging a template 82' which is provided by relieving an upper surface of the upper holder part 34' all the way round to provide a step which accommodates most of the radial extent to which the cam roll 80 projects beyond the pin 72, and thus provides a shoulder against which the roll bears while the pin 72 is just clear of the periphery of the upper holder part 34' and rib 30'.Thus, as the holder 16' rotates, the pin 72 engages the clay handle, removing the seam by pressing the clay of which it is constituted into the profile of the handle as the pin 72 traverses the length of the seam. By ensuring that the holder 16' makes at least one full revolution with the roll 80 in engagement with the template 82' the seam is removed from both the inside and outside of the handle, the circular outlines of the sleeve portions 40 allowing the pin to pass idly round from one side of the handle to the other.

The axis of the shaft 12, the pin 72 and the shafts 20, 20' when the holders 16, 16' are at the operating positions of the illustrative machine lie on a common plane, so that the pin 72, in being constantly urged towards the shaft 12, is able to pass diametrically through the axis about which the die rotates and is thus constantly urged towards the handles held by the holders 16, 16' in the de-seaming operation.

In an operating cycle of the illustrative machine, from the stage when an operator places a handle in the groove 32 of the lower holder part 18 (assuming the holder 16 to be at the loading and unloading position as shown in Figure 1), the operator lowers the upper holder part 34 by means of the handle 54 so that the handle to be deseamed is lightly clamped between the parts 18, 34. The arm 14 then swings through 1800; the machine can be arranged to operate continuously without interruption or initiation of the cycle can be effected manually by the operator.

During swinging of the arm 14, the guides 60, 60' are in rearward positions with the piston rod of the cylinder 64 projecting to the right (viewing Figure 1), holding the carriage 68 in a retracted position with the pin 72 in a chain line position depicted in Figure 1, by virtue of engagement of the plate 66 with an adjustable stop screw 89 on the carriage 68. With the carriage thus retracted, a microswitch 90 on the plate is closed by engagement with the carriage.

Electrical control circuitry of the illustrative machine is effective when the holder 16 reaches its operative position (the shaft 12 being restrained from rotating to hold the arm still in this position) to actuate the cylinder 64 and advance the guides 60, 60' to be left (view in Figure 1). As the guides advance, they take the carriage 68 with them until the cam 80 engages the template 82 to arrest further movement of the carriage towards the axis of the shaft 12. Thus, with continued advance of the plate 66, the microswitch -90 is released (the switch being closed) to actuate the motor 22 and cause the die 16 to rotate. The pin 72 now traverses the seam of the handle, the carriage moving to and fro on the guides 60, 60' in response to the profile of the template 82.When the holder 16 completes one revolution with the roll 80 in contact with the template 82, the cylinder 64 is actuated to retract the guides 60, 60', thus causing the plate 66 to withdraw the pin 72 from the handle; the microswitch 90 is opened by re-engagement with the carriage to stop the motor 22.To ensure that the holder 16 makes at least one complete revolution, and that it stops in a convenient orientation to allow the pin 72 to be withdrawn (rather than be trapped, as it otherwise might be, inside the handle) cams 92, 92' project radially from the flanges 19, 19' of the shafts 20, 20' so that they can cooperate with a microswitch 94 mounted on a ledge 96 secured to the bracket 10; conveniently, rotation of the holder is arrested only when the microswitch 94 is engaged by the cam, which is so orientated on the flange 19 as to cause the cam roll 80 to engage and disengage the template when the outside of the portion E of the handle or an adjacent part of the sleeve 40 is opposite the pin 72; the motors 22, 22' are of the brake type so that they hold the holders in the same orientation until they return to the operating position.

Closing of the switch 90 can also be arranged to signal completion of the cycle of operation of the illustrative machine, so that the circuit can be re-set ready to initiate another cycle on closing of the holder with a fresh handle in it at the loading position.

The arm 14 then swings round to bring the holder 16 to the loading and unloading station where the operator (unless automatic feed is provided) raises the upper holder part 34 and replaces the smooth, de-seamed, handle by another one to be de-seamed.

In carrying out the illustrative method using the illustrative machine it has been found satisfactory to use a smooth cylindrical pin 72 which is 0.3 cm. in diameter rotating at 20,000 r.p.m.

WHAT WE CLAIM IS: 1. A method of removing seams from cup handles in the clay state by causing a rotating pin to traverse the length of the seam, whereby the clay of the seam is pressed smoothly into the profile of the handle.

2. A method according to claim 1 wherein the axis of the pin is at right angles to the plane in which the seam lies.

3. A method according to either one of claims 1 and 2 wherein the pin is of uniform diameter where it engages the handle.

4. A method according to claim 3 wherein the pin has a smooth surface where it engages the handle.

5. A method according to any one of the preceding claims wherein the pin, where it engages the handle, has a diameter not exceeding 0.45 cm.

6. A method according to any one of the preceding claims wherein the pin rotates at at least 20,000 r.p.m.

7. A method according to any one of the preceding claims wherein, for the smoothing operation, the handle is held by a holder which leaves the seam exposed for engagement by the pin.

8. A cup handle de-seaming machine comprising a shaped holder by which a cup handle can be held with its seam exposed, a rotary pin means for rotating the pin, by the holder to be urged into engagement means for causing the pin and a handle held with one another in the operation of the machine, and means for causing relative movement to take place between the holder and the pin while the pin bears upon the handle in such a manner that the pin traverses the seam and presses the clay smoothly into the profile of the handle.

9. A machine according to claim 8 comprising a template of similar profile to the handle disposed to be engaged by a follower associated with the pin, and means for urging the follower into engagement with the template in the operation of the machine to limit approach of the pin to the handle to that necessary to smooth the clay of the seam into the profile of the handle.

10. A machine according to claim 9 in which the holder is mounted for rotation about an axis at right angles to the plane of the seam of a handle held by it, and a support for the pin mounted to slide to and fro along a path radial to the axis of rotation of the holder, the pin support being urged resiliently in such a direction along said path that the pin is constantly urged towards a handle held by the holder in the operation of the machine as it traverses

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. carriage 68 in a retracted position with the pin 72 in a chain line position depicted in Figure 1, by virtue of engagement of the plate 66 with an adjustable stop screw 89 on the carriage 68. With the carriage thus retracted, a microswitch 90 on the plate is closed by engagement with the carriage. Electrical control circuitry of the illustrative machine is effective when the holder 16 reaches its operative position (the shaft 12 being restrained from rotating to hold the arm still in this position) to actuate the cylinder 64 and advance the guides 60, 60' to be left (view in Figure 1). As the guides advance, they take the carriage 68 with them until the cam 80 engages the template 82 to arrest further movement of the carriage towards the axis of the shaft 12. Thus, with continued advance of the plate 66, the microswitch -90 is released (the switch being closed) to actuate the motor 22 and cause the die 16 to rotate. The pin 72 now traverses the seam of the handle, the carriage moving to and fro on the guides 60, 60' in response to the profile of the template 82.When the holder 16 completes one revolution with the roll 80 in contact with the template 82, the cylinder 64 is actuated to retract the guides 60, 60', thus causing the plate 66 to withdraw the pin 72 from the handle; the microswitch 90 is opened by re-engagement with the carriage to stop the motor 22.To ensure that the holder 16 makes at least one complete revolution, and that it stops in a convenient orientation to allow the pin 72 to be withdrawn (rather than be trapped, as it otherwise might be, inside the handle) cams 92, 92' project radially from the flanges 19, 19' of the shafts 20, 20' so that they can cooperate with a microswitch 94 mounted on a ledge 96 secured to the bracket 10; conveniently, rotation of the holder is arrested only when the microswitch 94 is engaged by the cam, which is so orientated on the flange 19 as to cause the cam roll 80 to engage and disengage the template when the outside of the portion E of the handle or an adjacent part of the sleeve 40 is opposite the pin 72; the motors 22, 22' are of the brake type so that they hold the holders in the same orientation until they return to the operating position. Closing of the switch 90 can also be arranged to signal completion of the cycle of operation of the illustrative machine, so that the circuit can be re-set ready to initiate another cycle on closing of the holder with a fresh handle in it at the loading position. The arm 14 then swings round to bring the holder 16 to the loading and unloading station where the operator (unless automatic feed is provided) raises the upper holder part 34 and replaces the smooth, de-seamed, handle by another one to be de-seamed. In carrying out the illustrative method using the illustrative machine it has been found satisfactory to use a smooth cylindrical pin 72 which is 0.3 cm. in diameter rotating at 20,000 r.p.m. WHAT WE CLAIM IS:

1. A method of removing seams from cup handles in the clay state by causing a rotating pin to traverse the length of the seam, whereby the clay of the seam is pressed smoothly into the profile of the handle.

its seam.

11. A machine according to either one of claims 9 and 10 in which the holder has two handle-engaging parts narrower than the handle so that the seam is exposed at both the inside and outside of the handle, means being provided for causing relative movement of approach and separation to take place between the holder parts to lightly clamp and release the handle.

12. A machine according to claim 11 in which the template is provided by one of the holder parts and is constituted by a shoulder set back from the edge of the holder part to provide a step wide enough to accommodate most of the projecting portion of a cam roll co-axial with the pin.

13. A machine according to either one of claims 11 and 12, in which the handleengaging parts of the holder are readily detachable from supporting means of the holder so that they can be changed for ones of different shape when the machine is to be used for handles of a different shape.

14. A machine according to any one of claims 10 to 13 comprising a plurality of rotatable holders mounted on conveyor means arranged to bring them in turn from a loading position to an operating position in which handles held by the holders are operated upon by the pin.

15. A machine according to claim 14 comprising power-operated means for causing the holders to rotate at the operating position.

16. A machine according to claim 15 comprising means for automatically terminating rotation of a holder at the operating station after one complete revolution.

17. A machine according to any one of claims 8 to 16 in which said rotary pin has a clay-engaging portion of uniform crosssection.

18. A machine according to claim 17 in which the clay-engaging portion of the pin is cylindrical and has a diameter not exceeding 0.45 cm.

19. A cup handle de-seaming machine constructed arranged and adapted to operate substantially as hereinbefore described with reference to the accompanying drawings.