US2410762A

US2410762A - Air blast nozzle device for enrobers or chocolate coating machines and the like

Info

Publication number: US2410762A
Application number: US506894A
Authority: US
Inventors: Tunley Allan Ashmead
Original assignee: Baker Perkins Ltd
Current assignee: Baker Perkins Ltd
Priority date: 1942-09-03
Filing date: 1943-10-19
Publication date: 1946-11-05
Anticipated expiration: 1963-11-05

Description

Nov. 5, 1946. v A. A. TUNLEY 2,410,762

AIR BLAST NOZZLE DEVICE FOR ENROBERS OR CHOCOLATE COATING MACHINES AND THE LIKE Filed Oct. 19, 1945 2 Sheets-Sheet l ET Q Nov. 5, 1946. A. A. TUNLEY 2,410,762

AIR BLAST NOZZLE DEVICE FOR ENROBERS OR CHOCOLATE COATING MACHINES AND THE LIKE Filed Oct. 19,-1945 2 Sheets-Sheet 2 Patented Nov. 5, 1946 AIR BLAST NOZZLE DEVICE FOR ENROBERS OR CHOCOLATE CQATING MACHINES AND THE LIKE Allan Ashmead Tunley, Peterhorough, England,

assignor to Baker Perkins Limited, Peterborough, Northampton, England Application October 19, 1943, Serial No. 506,894 In Great Britain September 3, 1942 4 Claims.

This invention relates to enrobers or machines for coating biscuits or sweetmeats or other socalled centres with chocolate or like setting coating.

It is customary in machines of the above kind to pass the centres upon a wire mesh band conveyor under a transverse curtain of liquid chocolate for coating or encasing the centres with a layer of chocolate, and to treat the coated centres While the chocolate is still in a plastic condition to the action of an air blast or blasts to distribute the coating evenly and remove surplus chocolate.

An aim of the present invention is to provide improved air blast nozzle means adapted to opcrate with greater efliciency than those at present known and to afford improved facilities for angular adjustment and regulation,

The invention consists in air blast nozzle means for enrobers, comprising two or more nozzles coupled to air supply means, and means whereby the direction of each nozzle may be adjusted independently of the other nozzle or nozzles so that the air blasts from the nozzles may be arranged to act in the same sense or direction or at oppositely inclined angles.

The invention also consists in providing air blast nozzle means having a hinged connection with an air supply duct (through which the air velocity is preferably constant) for enabling the direction angle of the nozzle to be adjusted while maintaining a smooth air flow from the duct to the nozzle without any abrupt change of direction or change of velocity.

According to the preferred form the nozzle comprises a pair of plates or flaps hinged on a transverse axis to the air supply duct, each plate being connected to one end of a lever, the other end of which is pivotally attached to a displaceable bar or element for manipulating the nozzle plates and adjusting them for altering the direction or angle of the blast. One or both of the levers may be adjustably connected to the bar or element for the purpose of enabling'the width of nozzle slot or opening to be regulated.

Double air blast nozzles have been employed hitherto. These known nozzle devices are adjustable for direction so that the angle of the air blast With respect to the centres may be altered but in all positions the two air streams of the pair always remain parallel. It has been found that these arrangements and their capacity for adjustment do not fulfil requirements since the blasts do not act uniformly upon the travelling centres and are liable to cause undue displacement in one direction or another of the chocolate, which may result in the denuding of the centres at some part or part and a local piling of the chocolate elsewhere, while certain of the sides of the centres are liable to be masked from the air action.

It is an object of the present invention to provide air blast means adapted to avoid the above difficulties and afford facilities for controlling the air blast treatment such as will ensure the desired distribution and uniform coating of chocolate upon the centres.

With this end in View the invention consists in providin a plurality of nozzles and means adapted to enable independent angular adjustment thereof such that the air blasts from the nozzles may be arranged to act in the same sense or direction or at oppositely inclined angles, in uch a way that the front and rear as well as the upper surface of the centres may be equally treatedto the air blast effect.

A further feature of the invention resides in supplying the nozzles with air in parallel through individual ducts from a main trunk or supply line.

With a view to further improving the efficiency of the air supply for the nozzles the invention also comprises the employment of a main trunk or supply line provided with a distribution box or hood so formed that air passes therethrough towards the nozzles at an increasing velocity.

The. invention also comprises in combination With a distribution box or hood according to the preceding paragraph, the provision of a pair of independent nozzle supply ducts to each of which nozzles are connected and so formed that the air passes from the box to the nozzles in parallel at a constant velocity.

The preferred form of distributing box comprises a pair ofair streams of gradually decreasing area-and a streamlined surface element for dividing the air streams and promoting a smooth flow of air at a gradually increasing velocity.

In the accompanying drawings:

Figure 1 is a front elevation of the improved nozzle means according to the invention;

Figure 2 is an end elevation looking from the right in Fig. 1, and

Figure 3 is a section on the line 3-3 of Fig. 1 showing certain details of construction of the nozzles. V

In carrying the invention into efiect according to one mode as described by way of example, the fan for providing the air supply for the nozzles is connected by a conduit I to a distributing box or casing 2 which in cross section (Figure 1, i. e. a section transverse of the enrober machine) is of truncated triangular shape with the base downwards, while in a section at rightangles (Figure 2) the outline is also of truncated triangular shape but with the base upward. The walls of the box or casing may be of sheet metal and in the centre of the box disposed symmetrically about the axis of the inflow of air from the fan is a surface element obstruction 3 which extends between the front and back walls 4 and 5 of the box so as to divide the air delivered by the fan into two equal streams 8 and I. The obstruction 3 may be formed by curved plate members connected together to form a body of roughly elliptical shape in cross section with tapering upper and lower ends to give a streamlining efiect, while the curvature of the plates is such that in conjunction with the outer side walls 8 and S of the box the air passages as viewed.

in cross-section of the machine are of gradually increasing dimensions to distribute the air flow evenly towards the nozzle means hereinafter described, which extend across the full width of the wire conveyor band for the centres to be treated. The obstruction plates terminate short of the delivery from the box so that the air streams merge or adjoin thereat.

The angle of the downwardly converging front and back walls 4 and 5 of the box 2 are so arranged that despite the increasing width of the air stream passages the cross-sectional area of the air streams gradually decreases from the supply entrance to the delivery towards the nozzle means. The distributing box 2 at the bottom or the delivery side is of rectangular shape in plan and afiords a transversely elongated delivery slot or mouth I to which is attached a pair of parallel-walled air ducts II, I2 which diverge outwardly as seen in Fig. 2, and present the aspect of a breeches pipe. The area of these ducts II and I2 is constant throughout, the arrangement being such that the air entering the box. 2 from the fan is divided first into two streams of gradually decreasing area so that gradually increasing air velocity is afiorded, and then each stream is again divided as it passes into' the breeches ducts II and i2 and travels therethrough at a uniform velocity.

The lower ends of the breeches ducts have mounted thereon a horizontal plate I3 below which the nozzles are mounted. At the outer ends of the horizontal plates depending side plates I4, I are secured between which the nozzle forming plates hereinafter described are located and these dependin plates I4, I5 serve to form a closure for the ends of the nozzleforming plates so that they provide air blast deliveries across the full Width of the conveyor band for the centres. The depending plates also form a convenient mounting for the rods or spindles by means of which the nozzle-forming plates are hinged to the horizontal plate atlthe delivery ends of the breeches ducts.

The nozzle-forming plates for the breeches ducts I I and I2 are counterparts one of the other so that the description thereof can be conveniently confined to the arrangements for one of the legs or branches of the breeches ducts.

The nozzle is formed by a pair of plates I6 and I1 each of which is secured around one of the bars or spindles I8 referred to above which lie parallel to oneanother and are mounted in slots I9 in the closure plates I4, I5. The bars or ably mounted in the slots I9 of the closure plates and the underside of the horizontal plate I3 is provided with a layer of felt 29 against which the curls of the plates I6, I! are bedded so that an air seal is afiorded. The spindles I8 at one end conveniently project through the closure plate !5 so that they may receive means for controlling and adjusting the angular position of the nozzle plates I6, I'I. These control means may comprise a pair of upwardly extending levers 2I, 22 each of which is secured to the projecting end of a hinging bar or spindle I8 and pivotally connected at its upper end to a horizontal manipulating link or bar 23. The pivotal connection of the lever 2I of one of the nozzle plates may be secured to the manipulating link 23 by a slot and

thumb screw connection

24, 25 so as to enable its nozzle plate I6 to be angularly adjusted with respect to the other nozzle plate I7 in order to alter the width of nozzle openin 26.

The tightening of the thumb screw 25 against the link also operates by the gripping action to hold the nozzle plates I6, I! in their adjusted angular positions relatively to the breeches ducts II, I2.

One of the levers 2! of the pair may have a downward extension 2'! located between a pair of stops 23 provided on the adjacent closure plate I5 so as to limit the displacement of the manipulating piece and consequently the range of angular adjustment of the nozzle. Below the air outlet from the nozzles and spaced therefrom a deflector 29 in the form of a flared channel plate is slun on a pair of end links 30 rotatably mounted upon one of the hinging spindles I8 for the nozzle flaps Iii, N. This deflector plate 29 when the nozzles are in operation is swung about its pivot out of the way of the air blast while to cut off the blast quickly it is dropped into position below the nozzle to deflect the air streams. According to one arrangement the deflector 29 is interlocked with the clutch through which the drive to the wire band carrying the centres is communicated, so that when this clutch is disengaged the deflector is dropped into position to obstruct the air blast issuing from the nozzles according to a known arrangement.

It will be appreciated from the above that the pairs of flaps I6, I! constituting the two nozzles can be turned about their pivotal axes or spindles I8 independently to vary the angle of direction of the air blasts as desired. For example, by operation of the manipulating links 23 the two nozzles can be disposed so that the air blasts converge or meet or they can be turned by the manipulating links so that the air blasts diverge or are directed in an opposite sense or direction. The flaps I6, H on operation of the manipulating link 23 for each nozzle, move together for directional displacement. If it is required to adjust the width of a nozzle opening the adjustable lever 2I of a pair i angularly adjusted to move the edge of its flap I 6 nearer to or further from the other flap edge by loosening the thumb screw 25 on the manipulating link and resetting the pivot end of the lever in the slot 24 and tightening up the screw in the new position.

In operation, assuming that the nozzles IS, H are adjusted to give converging air blasts, the centres on the Wire band as they arrive under the nozzles will first receive an air blast operating upon the front and top of the centre, while as the centre proceeds it will receive a blast directed at spindles- I 8 carrying the nozzles plates are rotat- 76 an oppositely inclined angle upon the upper surface of the centre and upon the rear side of the centre. If the nozzles I6, I1 are adjusted to afford diverging air blasts the centres similarly receive air directed against the top surface thereof and angles, each of said nozzles comprising a pair of plates hinged on transverse axes, each plate being rigidly connected to one end of a lever, the other ends of said levers being pivotally attached to a displaceable bar for manipulating the plates and adjusting them for altering the angle of the blast, one of said levers being adjustably connected to said bar for enabling the opening of the nozzle to be varied, said plates being secured in their adjusted position by a friction grip applied between one of said levers and the manipulating bar.

2. Apparatus for treating chocolate or like coated goods in an enrober to an air blast formed by two contiguous air streams comprising two juxtaposed air blast nozzles arranged in series, air suppply means to which said nozzles are connected, and means for adjusting the direction of each nozzle independently of the other, whereby the air blasts from the nozzles may be arranged to act in the same direction or at oppositely inclined angles, each of said nozzles comprising a pair of plates secured upon spindles pivotally mounted in end closure plates, levers mounted on said spindles atone end thereof, the free ends of the levers being operatively connected to a displaceable bar for manipulating the plates and adjusting them for altering the angle of the blast, one of said levers having an extension moving between stops on an end closure plate.

3. Apparatus for treating chocolate or like coated goods in an enrober to an air blast formed by two contiguous air streams comprising two juX taposed air blast nozzles arranged in series, air supply means to which said nozzles are connected, and means for adjusting the direction of each nozzle independently of the other, whereby the air blasts from the nozzles may be arranged to act in the same direction or at oppositely inclined angles, said nozzles being coupled to individual ducts from a main supply trunk whereby they are supplied in parallel and wherein the main supply trunk comprises a distribution hood having a streamlined surface element dividing the air stream into a pair of air streams of gradually decreasing area, and promoting a smooth flow of air at a gradually increasing velocity.

4. Air blast nozzle means for an enrober comprising an air supply duct, a nozzle coupled to said duct and comprising a pair of plates hinged to said duct on spaced transverse axes, each plate being rigidly connected to one end of a lever, the other ends of said levers being pivotally attached to a displaceable bar for manipulating the plates and adjusting them for altering the direction of the angle of the blast, said levers being adjustably connected to the bar for enabling the nozzle opening to be varied.

ALLAN ASHIWEAD TUNLEY.