GB2186180A

GB2186180A - A machine for continuously popping cereals

Info

Publication number: GB2186180A
Application number: GB08702678A
Authority: GB
Inventors: Lino Sacchi
Original assignee: SACCHI MECCANICHE SNC
Current assignee: SACCHI MECCANICHE SNC
Priority date: 1986-02-06
Filing date: 1987-02-06
Publication date: 1987-08-12
Also published as: IT1188337B; FR2593677B1; FR2593677A1; IT8619315A0; GB8702678D0; IT8619315A1; GB2186180B

Abstract

A machine for continuously popping cereals comprises a rotatable baking drum (2) with hopper (1) and screw feeder (19) to continuously feed the cereals into this drum, means (21) for collecting the dehydrated cereals flowing from the drum, hopper (5), screw conveyor (6) and hopper (7) with ball valve (8) for transporting the dehydrated cereals to an ejector cylinder (9) which is heated under pressure with steam via ports (13) and when plug 10 is opened, the moisture-laden cereals pops. Control and enable means are provided for causing all the operations to occur in the exact working sequence. <IMAGE>

Description

SPECIFICATION A machine for continuously popping cereals This invention relates to machines for producing popped cereals and more particularly to a machine of the above mentioned kind which operates in a continuous manner.

Known machines for popping cereals, in particular rice, are intended to produce quicklycooked dehydrated products and operate in a discontinuous manner. These machines comprise generally a rotatable baking drum which is heated by suitable heating means and into which the cereals to be popped are introduced. When the cereals have been baked and fully dehydrated, a steam jet is admitted into the rotatable drum until the pressure within the drum attains a predetermined value and then the drum is quickly opened so as to cause the cereal grains contained therein to be popped. Once the popping operation is terminated the cereals are discharged from the drum and the cycle is repeated.These machines operating in a discontinuous manner require much time for producing the popped cereals, since the drum is to be first charged with the suitable cereal amount and, once the popped cereals have been produced, the drum must be discharged and recharged again for the further cycle. Besides the time-consuming operation, much labour is required and this represents a disadvantage because the treatment cycles must be controlled by the operator and the machine has to be subjected to frequent servicing.

More particularly, the cereal popping machine operating in a continuous manner according to the present invention is of the type provided with a rotatable baking drum and is characterized in that it comprises feeding means associated to the baking drum for continuously feeding the cereals to the drum, means for collecting the dehydrated cereals flowing from the drum, continuous conveying means for transporting the dehydrated cereals from the collecting means to an ejector cylinder in which the cereals are subjected to the action of a steam jet under pressure, and a device for opening and closing the ejector cylinder in order to cause, when opened, the moisture-laden cereals to be popped.

According to the present invention there is provided a cereal popping machine for operating in a continuous manner, particularly for rice, the machine including a rotatable baking drum, feeding means associated with the baking drum for continuously feeding the cereal to said drum, means for collecting dehydrated cereal exiting from said drum, continuous conveying means for transporting the dehydrated cereal from the collecting means to an ejector cylinder in which the cereals are subjected to the action of a steam jet under pressure and a device for opening and closing the ejector cylinder in order to cause, when opened, the popping of the moisture-laden cereals.

Preferably, the means for feeding the cereals to the baking drum comprises a hopper having a screw feeder for continuously transporting the cereals to the baking drum. The screw feeder may have control means for controlling the revolving speed in accordance with the cereal amount to be fed to the machine.

The continuous conveying means may be formed as a screw elevator.

Preferably, an intermediate hopper is provided between the inlet of the ejector cylinder and the collecting means, the intermediate hopper being closed at a lower portion thereof by a valve.

Preferably the ejector cylinder has a closing and opening plug which is pneumatically controlled.

For a better understanding of the invention and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawing, in which: Figure 1 is a side elevational view of a cereal popping machine; Figure 2 is a plan view of the machine illustrated in Figure 1; and Figure 3 is a front elevational view of the machine illustrated in Figure 1.

As can be seen from Figure 1, this machine comprises a support frame. In this frame a baking drum 2 is supported, which is controlled by a motor-speed adjustor unit 1 5 causing the drum to be rotated at a predetermined speed by means of a chain drive 16.

The baking drum 2 is pivotally supported at its ends to the supporting frame through bearings and in a lower portion is provided with heating means in the form of a set of gas burners 3 which are connected to a common manifold 1 7 provided with a valve 4 for closing and opening the gas supply. The baking drum 2 is formed of a bundle of concentric pipes and has at the front end thereof an inlet duct 18 arranged below the outlet of a cereal feeding hopper 1 having a screw feeder 19 operated by a motor-speed adjustor unit 20.

The revolving speed of this feeder is controlled so as to maintain the flow rate of the product within the limits allowed by the machine.

A device 21 for receiving the dehydrated cereals flowing from the outlet 22 of the baking drum 2 is provided on the rear side of the baking drum 2. This device, through a duct 23 delivers by gravity the dehydrated cereals in a collecting hopper 5, provided with electronic sensors 24 for controlling the revolving speed of the screw feeder 19 and therefore the flow rate of the cereals fed to the machine. The collecting hopper 5 is connected to a screw elevator 6 operated by a motor 25 through a reduction gear 26 for lifting the dehydrated cereals from the collecting hopper 5 up to an intermediate hopper 7 provided in the lower portion thereof with a servo controlled ball valve 8 and connected to an ejector cylinder 9 in which the rice popping occurs and which is closed at its lower portion by a plug 10 operated by a pneumatic cylinder 11 and mounted on a slide 27.The shaft of the plug 10 is guided on guide plates 28 and the plug has a return spring 29 holding it in an opened position when the pneumatic cylinder 11 is disabled. The slide 27 is provided at a lower portion thereof with shock absorbers 12 abutting on stop elements fastened to the machine frame and intended to cushion the opening movement of the plug 10 which occurs in a very quick manner with the aid of the spring 29.

The slide 27 is laterally guided by uprights 30 extending up to the level of the inlet of the ejector cylinder 9.

The ejector cylinder 9 is provided at the upper portion thereof with inlet fittings 13 for the steam intended to moisten under pressure the cereal grains and to develop within the ejector cylinder 9 the desired pressure for the popping operation.

The closure plug 10 has an upper surface 31 inclined at 45O for projecting the cereal grains vertically flowing from the ejector cylinder 9 in a generally horizontal direction towards a collecting hopper (not shown) for the finished product and usually arranged in the front of the machine.

The feeding hopper 1 is provided also with an electronic level indicator (not shown) intended to hold the incoming cereals at a constant level.

All the above mentioned devices are controlled by a central unit 32. Of course, the machine is provided also with safety devices provided by the regulations in force permitting a self-contained and reliable operation.

If a malfunctioning occurs, a warning device is provided stopping the production cycle.

The operation of the machine is very simple, safe and reliable. The cereals come in the feeding hopper 1 and are held at a constant level by means of the electronic level indicator provided therefor. The screw feeder 19 controlled by the motor-speed adjustor unit 20, transports the cereals in the duct 18 communicating with the inlet of the baking drum 2 at a flow rate within the limits allowed by the machine under the control of the electronic sensors 24 applied to the collecting hopper 5.

Then, the product enters the rotating baking drum 2 which is heated by the gas burners 3, where the cereals are uniformly dried because of the continuous rotation of the baking drum.

Once the dried and dehydrated cereals are out of the baking drum 2, they move down the collecting device 21 and the duct 23, into the collecting hopper 5 and from here they are lifted by the screw elevator 6 into the intermediate hopper 7 where they remain waiting to pass to the popping cycle.

This cycle starts with the pneumatic closure of the plug 10 of the ejector cylinder 9. The plug closure causes the opening of the valve 8 which permits the dehydrated cereals to enter the ejector cylinder 9. When this is filled, the valve is closed and superheated steam is admitted into the chamber of the ejector cylinder 9 through the fitting 13. In the cylinder 9 the cereals are struck by this steam and, when the pressure attains a predetermined value, an enabling signal for opening the plug 10 is generated. When the plug 10 is in an open position, the sudden impact of the cereals with the atmosphere pressure causes the cereal moisture to be violently released, thereby allowing the dehydrated product to strongly increase in volume. As already said, the plug 10 has an upper surface inclined substantially at 45" so that the cereals, during the popping operation, by striking said inclined surface, are projected perpendicularly to the axis of the ejector cylinder 9 where they are collected by the collecting hopper provided on the front side of the machine.

Once the popping of the cereal grains has occurred, the plug 10, after a time period predetermined by a timer, closes again the ejector cylinder 9 and the cycle automatically restarts.

From the foregoing it is readily evident that by separating the two functions of drying and popping the cereals, a machine has been provided having a continuous operation mode which permits a better control of the process and a better quality of the product to be obtained, with reduced costs.

Claims

1. A cereal popping machine for operating in a continuous manner, particularly for rice, the machine including a rotatable baking drum, feeding means associated with the baking drum for continuously feeding the cereal to said drum, means for collecting dehydrated cereal exiting from said drum, continuous conveying means for transporting the dehydrated cereal from the collecting means to an ejector cylinder in which the cereals are subjected to the action of a steam jet under pressure and a device for opening and closing the ejector cylinder in order to cause, when opened, the popping of the moisture-laden cereals.

2. A machine as claimed in claim 1, wherein said means for feeding the cereals to the baking drum comprises a hopper having a screw feeder for continuously transporting the cereals to the baking drum.

3. A machine as claimed in claim 2, wherein the screw feeder has means to control it so as to rotate at a speed depending on the cereal amount to be fed to the machine.

4. A machine as claimed in claim 1, 2 or 3, wherein said continuous conveying means comprises a screw elevator.

5. A machine as claimed in any one of the preceding claims, wherein an intermediate hopper is provided between the inlet of said ejector cylinder and said collecting means, said intermediate hopper being closed at a lower portion thereof by a valve.

6. A machine as claimed in claim 2, or any one of claims 3 to 5 as appendant to claim 2, wherein the feeding hopper is provided with an electronic level indicator to hold the cereals contained therein at a constant level.

7. A machine as claimed in claim 3, or any one of claims 4 to 6 as appendant to claim 3, wherein said collecting means for the cereal exiting from the baking drum comprises a hopper provided with electronic sensors controlling the revolving speed of said screw feeder.

8. A machine as claimed in any one of the preceding claims, wherein said opening and closing device of the ejector cylinder is formed by a vertically sliding plug, provided with an inclined upper surface for projecting the popped cereal grains towards a collecting hopper intended to deliver the product to a packing station.

9. A machine as claimed in claim 8, wherein the plug for closing and opening said ejector cylinder is supported by a slide movable in a vertical direction and operated by a pneumatic cylinder.

10. A machine as claimed in any one of the preceding claims, wherein control and enable means are provided for causing all the machine operations to occur in the exact sequence.

11. A cereal popping machine, substantially as hereinbefore described with reference to the accompanying drawing.