JP3121833B2 - Wear drying apparatus, wear drying method, and automatic wear molding machine - Google Patents

Description

The present invention relates to an apparatus for drying ware (ceramics, ceramics), a method of drying ware, and an improvement in an automatic ware forming machine.

In a conventional automatic garment machine, such as for the manufacture of a mug (cylinder-shaped mug), the clay is fed into a plaster-of-paris mold. The mold is then transferred to a forming machine where the clay is pressed into the required shape to form the ware. Thereafter, the mold is passed under a plurality of hot air or gas streams to dry the ware, after which the ware is removed from the mold and subjected to further processing. Many such types are generally
It is conveyed to a molding machine in a carousel (rotary carriage of a carousel type) by an endless chain or a belt.

In accordance with the present invention, there is provided a wear drying apparatus comprising a mold capable of carrying a wear and defining a chamber for the wear, the apparatus comprising a selectively operable means for substantially closing the chamber. Means for creating a reduced pressure below ambient pressure in the room, and means for applying heat to the room, wherein the means for applying heat are arranged such that the wear can be positioned between the means for applying heat and the mold. Is provided, further comprising:

Preferably, the device includes means for providing a gas flow through the chamber. The gas stream can be air or any other suitable gas or gas mixture.

The closure means includes a cover that can engage the upper portion of the chamber.

The cover and / or the chamber may be relatively vertically movable relative to a lowered position where the cover engages the chamber and an elevated position where the cover is disengaged from the chamber.

One or more openings can be provided in the device to allow the flow of gas into the chamber. The opening can be provided in the cover.

The device may also further comprise means for sealingly closing the hole in the lower part of the chamber. The downhole closure means is operable by creating a sub-ambient vacuum in the chamber.

The downhole closing means includes a closing member movable between a position for closing the hole and a position off the hole, preferably spaced apart below the hole.

The heat application means is preferably configured so that it can be positioned in the hollow garment when the chamber is closed. Otherwise,
The heat application means can be positioned substantially adjacent to the flat wear in the room.

The heat application means can include an electrical heating element that can be placed on the cover. The heating element preferably provides radiant heat and is desirably controllable. The heating element is preferably
It may include multiple heating zones that may be separately controllable.
The heating element can be a source of infrared radiation.

One or more of the closures for allowing gas to flow into the chamber may be provided adjacent to the heat application means so that the gas flowing into the chamber is heated.

Means for creating a reduced pressure below ambient pressure may include a vacuum pump communicating with the interior of the chamber, preferably through a cover.

Communication with the vacuum pump can be provided through an outlet that allows gas to escape from the interior of the chamber. Preferably, the means for creating a reduced pressure below ambient pressure results in a gas flow substantially through the chamber.

Alternatively, the means for flowing gas through the chamber may be provided by pores in the mold structure. The coating can be applied to the mold to reduce the porosity to a suitable value.

According to the present invention, there is also provided an automatic wear molding machine including a drying device according to any of the above features.

The wear forming machine preferably includes a plurality of molds movable along an endless path. Some types are arranged to be located in the endless path at a certain point,
The drying device is preferably in operative relationship with the mold when the mold is in the path section, and preferably provides a drying unit for each of the molds in the path section. The endless track section is preferably located between a location where the clay is formed into a mold to form the garment and a location where the garment is removed from the mold.

The endless path section may be composed of a plurality of zones, and different drying conditions may be applied to the mold in each zone.

The molding machine may include means for introducing warm air into the mold after removing the molding wear and before filling the clay. The means for introducing warm air is preferably in flow communication with the arrangement for warming the air by flowing air across the heat application means of the drying device which is not located in the mold.

The drying device is located above the endless path section and can be mounted on a movable carrier that can be selectively lowered to engage the respective mold in the path and the carrier is a rotatable carousel (carousel type). ).

The machine can operate on hollow ware, flat ware, casting (cast) ware, molding ware and press ware.

Further in accordance with the present invention, there is provided a method of drying garment in a mold, the method comprising substantially closing the mold, creating a sub-ambient vacuum in the closed mold and facing the mold. The method includes applying heat to one or more sides of the garment and providing gas flow through the mold.

A reduced pressure below ambient pressure can be created only during a portion of the drying process. The reduced pressure below ambient pressure can be released when the percentage of water in the ware has been reduced to a predetermined percentage, for example in the range of 2-6%.

Embodiments of the present invention will be described by way of example only with reference to the accompanying drawings. In the drawings, FIG. 1 is a schematic side sectional view of a part of an automatic wear molding machine according to the present invention, FIG. 2 is a plan view of the molding machine of FIG. 1, and FIG. FIG. 4 is a schematic side view of a part of a molding machine, FIG. 4 is a schematic side sectional view of a part of an automatic wear molding machine according to a second embodiment of the present invention, and FIG. FIG. 6 is a schematic side sectional view of a part of an automatic wear molding machine according to the embodiment of FIG. 6, FIG. 6 is a drawing similar to FIG. 1 of the improved machine according to the present invention, and FIG. FIG. 2 is a schematic plan view of an automatic wear molding machine according to a specific example.

1 to 3 of the drawings show an automatic wear forming machine 10 suitable for forming hollow wear such as a mugg. Molding machine 10
Has an endless track 12 composed of outer and inner rails 14, 16 and a chain 18 running on the inner rail 16. The first portion 20 of the track 12 describes a substantial portion of the circle and the second portion 22 projects therefrom to form an elbow outside the circle.

A plurality of pairs of mold carriers 24 are movably positioned on the rails 14 and 16, respectively, in which case the outer carrier 24A is
And the inner carrier 24B is attached to the chain. An open-ended frustoconical casing 28 is provided between each pair of carriers 24. An appropriately shaped calcined gypsum mold 30 is carried in the casing 28. A passage 32 is provided through the base of the mold to allow placement of the clay within the mold and air to be drawn therefrom during molding. A washer 34 mounted on a vertically movable spindle 36 is located in the cavity 38 below the passage 32 so that the washer 34 closes the lower end of the passage 32 in the elevated position.

At the downstream end of the second portion 22 of the track relative to the direction of movement of the chain 18, there is provided a forming machine 40 for forming the clay into a ware in a mold 30. Just upstream of the molding machine 40 is a clay extruder 42 for feeding the required amount of clay into the mold 30. Upstream of the extruder 42 is a zone 44 in which warm air is blown to dry the mold prior to filling the clay when the mold is empty. At the upstream end 46 of the second part 22, a product transfer device (not shown) for removing the dried ware from the mold 30 by, for example, suction means is installed.

Above the first part 20 of the track, a carousel 48 is coaxially mounted, which comprises a number of vertically aligned rams along its circumference.
50 are mounted. A cap (cover) 52 is provided at the lower end of each ram 50. A lower lip 54 is formed along the periphery of the cap 52 with an annular seal 56 at its lower edge. The cap 52 is dimensioned so as to hermetically close one upper end of each of the mold casings 28 when it is lowered onto the mold casing 28;
Therefore, each mold 30 is confined in the chamber C. A cylindrical heating element 58 projects coaxially below the cap 52 and is dimensioned to fit within the wear article 60 within the mold 30. Electrical lead 62 extends from heating element 58 to cap 52
Extends through. A passage 64 also extends through the cap 52 and is connected to a vacuum pump via a flexible pipe 66.

In use, the chain 18 and the carousel 48 are driven and indexed in time with each other. Mold 30 is extruder 42
Is indexed below, the required amount of clay is supplied from there. Subsequently, the molding machine 40 presses the clay on the side surface of the mold 30 and forms the clay into a predetermined shape to form a wear article. As the clay is fed into the mold 30 and molded there, air is drawn through the holes 32 by another vacuum pump (not shown) to assist in these steps. When the mold 30 moves into the first part 20 of the track, the mold passes under the carousel 48,
The carousel is indexed to lower the cap 54 onto the mold by the action of each one of the rams 50. Cap 54
When installed in this manner, suction is applied through pipe 66 and passage 64. The reduced pressure created in mold 30 raises washer 34 and closes passage 32. At the same time, heat is applied to the interior of the mold by the heating element 58. As the mold moves along the first part until it reaches the second part of the track, heat and suction are applied, and when it reaches the second part, the ram 50
Raises the cap 52 away from the mold 30. Clothing 60
Is then removed from the mold 30 by the product transfer device and warm drying air is blown on the mold 30 in zone 44. The warming drying air may be heated by passing it around the heating element 58 in the raised position.

In the second embodiment, as shown in FIG. 4, a relatively narrow inlet passage 63A is provided through the heating element 58. The inlet passage 63A extends through the cap 52 and the inlet passage 63B.
In cooperation with, the inside of the mold 30 is communicated with the outside. The suction of the vacuum pump sucks air into the chamber C from outside through the inlet passages 63A and 63B. As the air flows through the inlet passages 63A, B, the air is heated by the heating element 58. Air flows from inlet passages 63A, B through chamber C and exits through passage 64. This warmed air flow assists in the elimination of the relatively moist atmosphere in chamber C and promotes the drying of the ware by replacing it with warmed dry air. The warm air flow allows the temperature in chamber C to be reduced and still achieve effective drying. This saves energy and helps extend the life of the mold. Instead of using air, a specific gas or gas mixture source may be connected to inlet 63B.

It should be understood that the size and number of the inlet passages 63A, B are predetermined for the capacity of the vacuum pump and the degree of pressure reduction from the ambient pressure required in the chamber C. Molding machine 40
Can be used to form and dry casting, molding and pressware, including hollow and flatware.

FIG. 5 shows a part of a wear forming machine according to a third embodiment of the present invention for drying flat wear. The molding machine includes a mold casing 128 that can be mounted between a pair of carriers (not shown) similar to carriers 24A, B. A plaster of Paris mold 130 is supported within the casing 128. A passage 132 is formed in the base of the mold 139 to allow placement of the clay within the mold and air to be drawn from the mold during molding. Washer 34 and spindle 36 described above
A washer and spindle (not shown) may be provided to operate in a similar manner to close the end of the passage 132.

A cap 152 is provided at the lower end of each ram in the carousel 48. Cap 152 has a wall 154 which extends downwardly around, which forms a chamber C ₂ and the casing 128 and sealed at its lower edge in a similar manner as described above. A planar ceramic heating element 158 extends below the cap 152 to a position just above the wear in the mold 130. The planar heating element 158 includes a plurality of coaxial heating elements arranged in an annular zone to allow its heating effect to be varied radially. For example, if the wear is of a relatively small diameter (saucer, saucer), a heating action that is small toward the periphery of the casing 128 and large toward the center is required. As a result, only the zone towards the center of the heating element 158 is operated. An electrical lead 162 extends through the cap 152 from the heating element 158 to a heating controller (not shown). Heating element 1
58 is an infrared source, but any other suitable heating means may also be used.

A passage 164 extends through the cap 152 and leads to a vacuum pump. One or more additional passages 163 extend through wall 154. These passages 163 provide an inlet to the chamber C _2. Air is sucked through the inlet 163 to the chamber C ₂ under the suction effect provided by the vacuum pump. Air flows through chamber C ₂ and exits through passage 164. In the air flows through the chamber C _2, air is warmed by the heating element 158. The flow of air through the chamber removes moisture in the room atmosphere and thereby promotes drying of the garment. Insulation and insulation 165 is provided below the cap to help reduce heat loss through the cap.

FIG. 7 shows a wear molding machine 20 according to a fourth embodiment of the present invention.
Indicates 0. The molding machine 200 has an endless track 212 that is substantially rectangular but one end of which protrudes outward to form an elbow 222. The trajectory can take any conventional form as shown in FIGS. 1-3 and will not be described in further detail. A plurality of mold casings 128 supporting a mold 130 of the type illustrated in FIG. 5 are movably arranged along the track, and their movement is accurately timed and indexed.

Each side of the track has a section 270 that forms a location for ten adjacent casings 128. Between each side of the rectangle are formed additional compartments 272 (here four) giving 10 positions for movement of the casing 128. Means are provided for moving the casing 128 between each compartment, usually all ten simultaneously in each compartment, from compartment to compartment. Such a vehicle may include a pivot lift bar (not shown).

A cap 152 (fifth section) is provided above each of the four rows of sections 272.
Figure) is provided. The cap 152 is movable by a ram to engage or disengage a casing 128 provided therebelow to enable drying of the flatware held by the casing.

A wear forming machine 240 is provided at the top of the elbow 222.
Upstream of the molding machine 240, a mold cleaning and mold conditioning equipment (not shown) is installed. Further upstream of this facility is a stage (not shown) for removing the ware from the casing 128. The wear removal stage is
The ware may be connected to a similar device for white drying (a drying step in which the moisture is further dried to about 1-2%). In such a similar device, the wear is of course not mounted in the mold, but a suitable closable container for supporting the wear is provided. The white drying device can then be connected to a kiln.

In use, the track 212 rotates clockwise as shown in FIG. The orbital movement of the casing 12
8 is precisely indexed to ensure that it moves exactly where it is needed and moves to the exact required location.
When ten casings occupy each of the positions in compartment 270, the casings are pivoted by the pivot arms at
It is moved to the position of each of the two lowest compartments (as shown in FIG. 7). In section 272, cap 152 is lowered onto casing 128 to provide primary drying at the required temperature for the required period. In the primary drying section 272,
It has often been found to be beneficial to apply heat only without applying reduced pressure, thereby stabilizing the garment. When needed, the casing is moved to the next compartment 272,
Here, additional drying is applied under reduced pressure. Two such additional drying steps are performed in additional section 272,
The casing 128 is finally moved up the track 212 (see FIG. 7). Thereafter, the casing is again correctly indexed and moved to a removal station where the wear is removed for subsequent drying and firing. The casing 128 and the mold 130 therein are then cleaned and conditioned.

The automatic wear molding machine described above has a number of beneficial features. Establishing reduced pressure in the mold lowers the boiling point of water,
It gives improved drying. If gas flow is provided from the vacuum pump and through the chamber, the water vapor generated from the garment is removed to further improve drying. Closing the mold provides a more localized and more efficient heating of the garment. A heating element is located within the wear for hollow wear and close to the wear for flat wear, and the fact that the wear is located between the heating element and the mold provides a heating effect on the mold. Less, thus reducing mold damage. Thus, the required drying can be performed more efficiently and quickly.

Using the molding machine described above, the drying time was reduced from 90-100 seconds to 50-55 seconds for hollow wear and from 19-20 minutes to 3-4 minutes for flat wear. Thus, it is possible to produce a molding machine with 28 dies instead of 45 dies as in the prior art, reducing the required floor space, which is often particularly useful. The machine is ideally suited for relatively small-scale operations in that no gas is required and no removal of combustion waste gases is required.

The aforementioned drying process mainly refers to a drying step commonly referred to as "demolding". This is a dry state that allows the garment to be removed from the mold when it reaches that state. The percentage of water in the garment at this stage usually ranges from 10 to 15%.

Often, the next step is to further dry the ware following removal from the mold until the percentage of water in the ware is in the range of 1-2%. This is commonly referred to as "white drying". The present invention can be easily used in "white drying" ware. In this case, the ware is placed on a support, such as a perforated plate, in a substantially sealed container. A connection to a vacuum pump and a heating element are provided in the container in substantially the same manner as described above. A gas inlet may also be provided in the container as described above. During operation, an atmosphere below ambient pressure is introduced into the vessel, and also, if applicable, gas flow through the vessel as described above. The vacuum pump is stopped before the garment is finally dried, probably when the moisture content is on the order of 3-5%. Release of vacuum before final drying was found to reduce the probability of cracking of the dried ware.

Various other modifications may be made without departing from the scope of the invention. For example, as illustrated in FIG. 6, a washer for closing the passage through the mold is provided on the mold casing 2.
8, so it can be replaced with a short stroke ram 70 closing the bottom of the mold. The mold and / or cap can be moved by different means, and the cap can be raised and lowered by means other than the described ram, or the mold itself, rather than the cap, can be raised and lowered.

Also, caps 52, 152 and corresponding lips 54 and walls 154
Can be sealed directly onto the mold 30,130. This eliminates the need for disposing the casings 28,128. In such a case, the gas inlet may be provided by pores in the mold structure itself. Further, a coating can be applied to the mold to reduce the porosity of the mold to an appropriate value so that the drying process as described above works. Alternatively or additionally, molds made of materials other than gypsum can be used.

────────────────────────────────────────────────── ─── Continuing the front page (72) Inventor Wedgwood, Sydney Estee 59 England UK Javi Staffordshire, Newcastle-le-Under-Lyme, Chesterton, Holditch Industrial Estate, Spencroft Road, Inteldoli Limited (no address) (56) References JP-A-64-14178 (JP, A) US Patent 2561629 (US, A) West German Patent Application 3104499 (DE, A1) UK Patent Application 2034631 (GB, A) UK Patent Application 631656 (GB, A) British Patent Application Publication 1037856 (GB, A) French Patent Application Publication 2277658 (FR, A1) French Patent Application Publication 1368847 (FR, A1) French Patent Application Publication 242503 (FR, A1) ) French patent issued Publication 2422915 (FR, A 1) French Patent Application Publication 979120 (FR, A 1) ( 58) investigated the field (Int.Cl. ^7, DB name) B28B 11/00 C04B 33/30

Claims (9)

(57) [Claims] 1. A ware drying apparatus comprising a mold capable of carrying ware and defining a chamber for the ware, wherein the apparatus has selectively operable means for substantially closing the chamber. A means for creating a reduced pressure below ambient pressure in the chamber and a means for applying heat to the chamber, wherein the heat is arranged so that the wear can be positioned between the means for thermal use and the mold. A wear drying device, further comprising a target means. 2. The apparatus of claim 1 wherein the apparatus includes means for providing a gas flow through the chamber. 3. The wear drying apparatus according to claim 1, wherein the closing means includes a cover engageable with the upper part of the chamber. 4. A wear dryer according to claim 3, wherein the cover and / or the chamber is relatively vertically movable between a lowered position where the cover engages the chamber and a raised position where the cover is disengaged from the chamber. . 5. A wear drying apparatus according to claim 3, wherein the apparatus is provided with one or more openings through which a gas stream can be introduced into the room. 6. The heat application means is configured to be positioned within the hollow garment when the chamber is closed.
A wear drying device according to any one of the preceding claims. 7. A wear drying apparatus according to claim 1, wherein the heat application means can be positioned substantially adjacent to the flat wear in the room. 8. An automatic wear molding machine comprising a wear drying device according to claim 1. 9. A method for drying a garment in a mold, wherein the mold is substantially closed, a vacuum is created below ambient pressure in the closed mold and heat is applied to one or more sides of the garment not facing the mold. A method of drying in-mold wear comprising applying a gas flow through the mold.