US3782428A

US3782428A - Food dispensing apparatus

Info

Publication number: US3782428A
Application number: US00164337A
Authority: US
Inventors: T Cartwright; J Wightman
Original assignee: AYERS J AND CO Ltd
Current assignee: AYERS J AND CO Ltd
Priority date: 1970-08-22
Filing date: 1971-07-20
Publication date: 1974-01-01
Anticipated expiration: 1991-01-01

Abstract

Apparatus for dispensing batter, or other pasty foods, into a container on a travelling conveyor, including a motor driven pump dispenser and a motor driven conveyor and including means for reversing the direction of the pump for a brief moment at the end of each dispensing cycle, and simultaneously giving the container a vertical ''''jogging'''' movement. At the start of the next cycle the movement of the container is delayed by a stop for a brief interval after the pump has started to dispense. The pump itself is of the gear type and one or both of the gear pinions has cutaway teeth to provide cavities in which small fruits can be carried through the pump without being damaged.

Description

United States Patent Cartwright et a1. Jan. 1, 1974 [54] 0 1) DISPENSING APPARATUS 2,103,817 12 1937 Johnson 141/116 [75] Inventors: Thomas Edward Cartwright; John Cllfford Wightman, both of 771,137 9 1904 Frerking 222/281 Glamorgan, ng 1,945,065 1/1934 Mosslang 222 281 x 603,081 4/1898 Harton 222 145 [73] Assgnee' f f Ayers and Cmnpany 3,489,321 1 1970 Kirschmann 222/145 x Limited, Glamorgan, England [22] Filed: July 20, 1971 Primary Examiner-Wayne A. Morse, Jr.

Appl. No.: 164,337

Foreign Application Priority Data Aug. 22, 1970 Great Britain 40,553/70 [56] References Cited UNITED STATES PATENTS 3,536,236 10/1970 Rasmusson 141/129 X 1.827.416 10/1931 Birdsall ..14l/1l6X Attorney-William D. Hall et al.

[5 7] ABSTRACT Apparatus for dispensing batter, or other pasty foods, into a container on a travelling conveyor, including a motor driven pump dispenser and a motor driven conveyor and including means for reversing the direction of the pump for a brief moment at the end of each dispensing cycle, and simultaneously giving the container a vertical jogging movement. At the start of the next cycle the movement of the container is delayed by a stop for a brief interval after the pump has started to dispense. The pump itself is of the gear type and one or both of the gear pinions has cut-away teeth to provide cavities in which small fruits can be carried through the pump without being damaged.

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ATTORNEY PATENTED H974 3.782.428

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sum 5 or 5 ATTORNEY FOOD DISPENSING APPARATUS This invention relates to apparatus for dispensing semi-solid materials in a controlled manner and is particularly though not exclusively applicable to dispensing apparatus for discharging controlled quantities of batter or like bakery trade products, or filling materi als, for use in the food industry. For example the apparatus may be used to deliver semi-liquid or plastic materials such as batter, jelly, cream custard or other pastry-cooks fillings into pastry or other receivers such as cakes, tarts, or onto baking trays or other receptacles.

Difficulties have been experienced in controlling the discharge of such materials owing partly to the fact that the material tends to dribble from the nozzle when the main flow is shut off. Also in some cases the initial discharge is either relatively slow or is in the form of an enlarged globule. Thus for example if discharging batter to form small cream cakes such as eclaircases the batter may produce an uneven strip with a tapered or enlarged end and this can be unsightly and can also cause difficulties if the products are to be packed into standard pre-formed packaging containers.

Accordingly it is an object of the invention to provide an improved method and apparatus for controlling the discharge of such materials.

From one aspect the invention consists broadly in apparatus for dispensing a liquid or semi-solid material such as a paste, batter or pastry-cooks filling, comprising means for driving a rotary pump in one direction to dispense the material through a nozzle, means for stopping the pump to interrupt the delivery, means for driving the pump momentarily in the reverse direction immediately after stoppage, and means for jogging a conveyor or other support for a container into which the material is dispensed, to cause the container to move generally vertically towards and away from the nozzle, at, or approximately at, the instant when the pump drive is stopped.

According to a preferred feature of the invention the means for driving the pump comprises two contrarotating drive elements connected to drive the pump in parallel through clutches. The clutches may be electromagnetically operated, and the apparatus preferably includes clutch control means for selectively engaging one clutch and disengaging the other, and actuated automatically when the discharge of material is stopped and/or commenced.

According to another preferred feature of the invention the apparatus includes means forautomatically interrupting the reverse drive to the pump after a predetermined short period, or after a predetermined movement in the reverse direction.

FOr example the apparatus may comprise a unidirectional clutch or driving device operatively connected to the pump or the pump drive and arranged to over-run when the pump is driven in the forward direction, and to become engaged when the pump is driven in the reverse direction, the said uni-directional driving device being coupled to means for controlling the extent or duration of the reverse rotation.

From anotheraspect the invention consists in apparatus for dispensing a viscous, pasty, or semi-solid material such as a food paste or batter into or onto a receiver, including a support for the receiver, a stop or holding device to locate the receiver at a start position, dispensing means for discharging the material, control means for actuating the dispensing means, means for automatically withdrawing the stop or deactivating the holding device so that the receiver can advance past the dispensing means, and time delay means arranged to delay the withdrawal of the stop or the deactivation of the holding device until after the dispensing means has started to operate.

The invention is particularly applicable to apparatus intended to place a layer of a material such as batter uniformly over a small elongated tray. in such conditions it is found that if the dispensing means is operated simultaneously as the tray starts to move the batter will not be spread uniformly over the tray, and in particular there may be a shortage of batter at the leading end of the tray. The delay afforded by the invention provides a more uniform distribution. The time delay means may comprise an electronic time delay circuit, and in any case the time delay factor is preferably adjustable.

The invention is also concerned with the design of a suitable pump for handling dough mixtures containing small objects such as raisins or fruit, which should not be damaged or brusied as they pass through the pump, and from another aspect the invention consists broadly in a pump for displacing liquid, viscous, pasty, or semisolid materials, especially materials containing small bodies of different consistency, comprising a pair of parallel spaced rotary toothed members arranged to rotate in opposite directions, with some overlap or interengagement of the teeth of the two members, the members being so formed that small bodies can pass between the two members as they rotate, being trapped in cavities formed successively between the members as they rotate, while substantially effective sealing contact is formed between parts of the two members in succession as they rotate.

it will be appreciated that it is not sufficient merely to provide clearance between all the teeth of the two rotary members. If adequate clearance is provided then obviously a small body such as a raisin will not be crushed but the clearance will destroy the effectiveness of the seal between the two rotary members and the v proper pumping action will be lost. The present invention provides sufficient clearance to ensure that small bodies will not be crushed and at the same time maintains a satisfactory seal and efficient pumping action.

The invention may be performed in various ways and one specific embodiment will now be described by way of example with reference to the accompanying drawings, in which FIG. 1 is a diagrammatic illustration showing the main mechanical components of a machine for dispensing a material such as batter into a succession of flat trays or pans moving on a conveyor,

FIGS. 2 and 3 are diagrammatic views showing two operative positions of the freewheel mechanism and the associated cam and microswitches,

FIG. 4 is a diagrammatic circuit arrangement showing the main electrical components,

FIG. 5 is a diagrammatic side view, on an enlarged scale, showing a tray on the conveyor, below the discharge nozzle, and a movable stop locating the tray in its starting position,

FIG. 6 is a fragmentary end view onto the stop actuating mechanism of FIG. 5,

FlG. 7 is a somewhat diagrammatic side elevation of the conveyor table showing the jogging linkage,

FIG. 8 is a sectional view through the combined hopper and pump casing from which the batter is dis pensed,

FIG. 9 is a detailed sectional end view on an enlarged scale showing the two pinions of the dispensing pump, and

FIG. 10 is a sectional view on the line X X in FIG. 9.

As illustrated in FIG. 1 the apparatus comprises essentially a horizontal power driven conveyor 10 for transporting a baking tray or other receptacle below a batter dispensing unit 11 which incorporates a gear pump device. The apparatus includes two motors 12 and 13. Motor 12 is arranged to drive the conveyor 10 and also to apply a temporary reversing movement to the pump in the dispenser 11, and to operate a jogging" device for momentarily lowering the conveyor table at the moment when the dispensing pump is shut off, so as to assist in breaking any dribbles or threads of batter. As shown this motor 12 is connected through a power train 14, to a variable speed transmission device 15, the output of which is connected through a magnetically operated clutch 16 and through a magnetically operated brake 17 to a gear box 18 from which a belt drive 19 is connected to the driven rollers of the conveyor 10. The power train 14 is also permanently connected to a reversing countershaft 20 which is coupled through a magnetically operated reversing clutch 21 to an input shaft 25 ofa gear box 26, so as to reverse the rotation of the gear box, as will be explained below.

The pump driving motor 13 is connected through a power transmission train 30, and through an infinitely variable transmission device 31, to a magnetically operated pump driving clutch 32, also connected to the input shaft drive 25 of the gear box 26. The output shaft of the gear box is permanently connected to the input drive shaft 33 which is detachably connectable to the gears of the pump unit in the dispenser 11. The output shaft of the gear box 26 is surrounded by a freewheel ring 34 arranged to allow the shaft 33 to over-run freely in the forward direction of the pump and to become engaged when the pump shaft is reversed. This freewheel ring is connected through a linkage 35 to a dog-toothed input member 36 of a jogging" clutch, having an axially movable dog-type output member 37 splined to a jogging shaft 38. A clutch control fork 29 is actuated automatically by a solenoid 28 to control the engagement or disengagement of the clutch at the end of each cycle, and the jogging" shaft 38 has operating levers 39 connected to the conveyor table to produce limited vertical jogging" movements of the table synchronised with the reversal of the pump at the end of each dispensing stage. As shown in FIG. 4 the two magnetically operated

clutches

21 and 32 are selectively and oppositely energised by means of a reversing relay switch 40 having two sets of

contacts

41,42 controlled by a rocking lever 43 actuated by the relay so that when one set of contacts is closed the other is opened and vice versa.

The reversing clutch 21 is also in circuit with a microswitch 45 having an operating element engaged by a cam 46. As shown in FIG. 4 this is a linear cam but in the practical construction this cam 46 is a rotary face cam element connected to the freewheel ring 34 as shown in FIG. 1 and also diagrammatically in FIGS. 2 and 3. The cam has a face 47 to engage the operating arm of the microswitch 45 and also a projection 48 is arranged to engage a pivoted trip element 49 of a second microswitch 50. The lower part of FIG. 4 illustrates the position of the cam 46 in engagement with the trip element 49 and in this position the microswitch 50 is closed. This microswitch is connected in a circuit comprising a pulse initiated variable timer 52, a delay timer 53 and a relay 54, this circuit also being connected to the electrical supply 55 which is arranged to energise the forward and

reverse clutches

32 and 21.

The apparatus is arranged to operate generally as follows. When the main starting switch is closed to energise the two motors 12 and 13, the freewheel cam 46 is in the position shown in the lower part of FIG. 4 so that the microswitch 50 is closed and the microswitch 45 is open. The relay 40 is energised to close the forward clutch contacts 41 and to open the reverse contacts 42. The forward driving clutch 32 is therefore engaged and the reverse clutch disengaged. The conveyor driving clutch 16 is also engaged and the magnetic brake l7 disengaged. The conveyor motor 12 therefore drives the conveyor in a forward direction through the variable speed drive 15 and also simultaneously drives the reversing countershaft 20, but this latter shaft is disengaged from the gear box 26 and has no effect thereon. The pump motor 13 drives through the variable ratio device 31, and the engaged forward clutch 32, to cause the dispensing pump to discharge batter onto a tray carried by the conveyor. The forward driving movement of the conveyor is related to the speed of the pump by appropriate control of the two variable speed devices 15 and 31 so as to produce the required depth of batter on the tray, and the forward movement of the tray at the start of each dispensing sequence is delayed briefly by a timer system as described in detail with reference to FIGS. 4 and 5. The two driving movements, to the conveyor and the pump, continue for a period selected by the timer 52, which may for example be about four seconds. At the end of this period the timer generates a pulse which operates the relay 54 to reverse the position of the contacts of the relay switch 40 thus opening the forward clutch contacts and closing the reverse contacts 42. The forward clutch 32 is therefore immediately disengaged thus interrupting forward drive to the dispenser pump and, since the microswitch 45 is closed, the reversing clutch 21 is engaged thus instantaneously coupling the continually rotating reversing countershaft 20 to the gear box 36. The output shaft to the gear box is thus driven in the reverse direction so reversing the direction of rotation of the gears in the pump, thus ensuring that the delivery of the batter is instantaneously cut off and eliminating or minimising any dribble or excess delivery. The reversal of the pump drive is limited to an angle of for example 30 and during this angular movement the cam plate and the freewheel ring 34 move between the positions illustrated in FIGS. 2 and 3. FIG. 2 represents the positions of the parts corresponding to the condition shown in the upper part of FIG. 4 and FIG. 3 corresponds to the condition shown in the lower part of FIG. 4. In FIG. 2 the cam plate 46 is shown in its limiting anticlockwise position held against a stop by a spring 61, and the freewheel mechanism is illus trated diagrammatically by a pawl 62 attached to the cam 46 and arranged to engage a ratchet tooth 63 on the shaft 33. When the shaft 33 is driven in the forward direction i.e. counterclockwise in FIG. 2, the pawl 62 over-runs but when the shaft 33 is reversed the pawl engages the ratchet tooth and the cam plate 46 is driven with the shaft in a clockwise direction towards the position illustrated in FIG. 3. During this movement the freewheel ring 34 acts through the linkage 35 and through the jogging clutch 36,37 (which is assumed to be engaged by the fork 29) to rotate the jogging shaft 38 and to cause the conveyor table to be depressed momentarily (as illustrated in FIG. 7) so as to assist in breaking the strands of batter between the delivery nozzles of the depositor pump and the pump of the baking tray. When the cam plate reaches the position illustrated in FIG. 3 the microswitch operating element 47 moves clear of the face of the cam so that the switch 45 is opened, thus disengaging the reversing clutch 21. Simultaneously the tripping element 49 of microswitch 50 is engaged by the part 48 to close the microswitch 50. This initiates the output pulse through the auxiliary delay timer 53, which imposes a delay of approximately 0.2 seconds, before again energising the relay 54 to reverse the relay switch 40 and thus reengage the forward drive.

The conveyor mounting and jogging arrangements are illustrated in detail in FIG. 7. The conveyor rollers 90 are carried by horizontal frame members 92 constituting the conveyor table and all the rollers are driven in synchronism in the same direction by means of sprockets (not shown) at their ends, engaged by a chain drive device coupled to the conveyor drive illustrated at 19 in FIG. 1. The conveyor table frame 92 has four supporting legs 93, the lower end of each end being pivotally connected to one arm 94 of a bellcrank lever, pivotally' connected on a pin 95 to an arm 96 ofa second bellcrank lever pivotally supported on a stationary pivot pin 97 in a bearing carried by a base support frame 100. The second arm 101 of the first bellcrank lever is adjustably connected to the second arm 102 of the second bellcrank lever by means of a screwthreaded adjusting bolt 103 anchored to the lower end of the lever 102 and passing freely through an anchored sleeve in the lower end of the lever 101. An adjusting knob 104 can be tightened on the bolt 103 to move the lower ends of these levers 101 and 102 towards or away from each other thus varying the angular relationship between the

levers

94 and 96. This adjustment thus adjusts and pre-sets the vertical height of the conveyor table in relation to the fixed pivot mountings 97.

The lower ends of the levers 102 have extensions connected to horizontal springs 105 acting in a direction to rotate the bellcrank levers so as to raise the conveyor table. The pivot shafts 97 on which the bellcrank levers 96,102 are mounted, are in fact connected mechanically to the output shaft 38 of the jogging" clutch 36,37.

Thus in operation when the reversing clutch 21 is engaged to cause the output shaft of the gear box 26 to change direction, the linkage 35 acts through the jogging" clutch 36,37, to cause the shaft 38 to be rotated through a limited distance. This corresponds to clockwise rotation of the shaft 97 as seen in FIG. 7 and thus causes the conveyor table frame 92 to be lowered against the action of the springs 105. This movement is limited by a stop and when the reversing clutch 21 is disengaged the table is returned rapidly to its upper position under the action of the springs 105.

FIGS. 5 and 6 illustrate a movable stop for temporarily holding a container tray on the conveyor, and automatic control means for withdrawing the stop at the selected instant. Mounted on a part 70 secured to the frame carrying the power driven conveyor rollers 90 is an adjustable stop 72 mounted on a bracket 73 carried by a square section pivoted shaft 74, and arranged in its normal operative position as shown in FIG. 5 to project upwards above the normal path of travel of trays 75 on the conveyor rollers, so as to halt a tray with its front edge 76 immediately below the discharge nozzle 77 of the dispenser 11. The bracket 73 can be adjusted lengthwise along the shaft 74 to determine this starting position of the tray. The shaft 74 is urged counterclockwise into the operative position by means of a spring 78 and has an arm 79 connected to a solenoid 80 which when energised rocks the shaft to swing the stop 72 downwards below the path of movement of the trays. The conveyor rollers are continuously driven so that the tray starts to advance past the filling head immediately the stop is withdrawn. Alternatively, as mentioned above, the conveyor drive may be interrupted, for example, by means of an electromagnetic clutch, which is connected in the same control circuit and energised simultaneously as the solenoid is operated to withdraw the stop. In any case the movement of the conveyor rollers is selected so as to advance the trays slowly beneath the filling head such that a thin layer of batter of the required thickness is deposited on each tray.

In order to ensure that the batter fills the whole tray, and in particular the part of the tray adjacent the leading edge, an electronic time delay circuit is incorporated to provide a time delay factor between the engagement of the clutch 32 in the drive to the dispensing pump, and the operation of the solenoid 80 which withdraws the stop.

Thus as shown in FIG. 4 the electrical connections to the electromagnetic clutch 32 are also connected in parallel with a stop circuit including the solenoid 80, an adjustable electronic delay timer 81, and a two-way manually operable switch 82. With the switch in the position shown the timer 81 is cut out of the circuit, and the stop solenoid 80 will be energised simultaneously with the clutch 32: this is convenient for some purposes.,When the switch 82 is in its alternative position the timer 81 is included in the solenoid circuit, and imposes a delay of say 0.5 seconds on the operation of the solenoid 80, thus allowing the dispensing pump to start operation a short interval before the stop 72 is withdrawn. This delay is adjustable by conventional electrical means to vary the interval.

In operation the machine will be started in the normal manner by a start switch and the control circuit will first engage the clutch in the forward drive of the dispensing head so that batter starts to extrude from the nozzle slot. The initial edge of the batter blanket may be rather thin and a small time interval is needed for the leading edge of this blanket" to move downwards from the nozzle into the leading edge of the tray. After the selected time interval determined by the time delay circuit, when a small part of the batter blanket has moved onto the tray, the stop solenoid is then automatically actuated to withdraw the stop and the tray starts to advance beneath the filling head so that a layer of batter of substantially uniform thickness is deposited.

When the tray is completely filled, i.e. when the rear edge of the tray reaches the position below the filling head, the drive to the dispensing pump is automatically interrupted and the pump is reversed for a short interval as described above.

The hopper and dispenser gear pump is illustrated in FIGS. 8 and 9, in which the hopper is shown having tapered walls 110 leading to the inlet of a pump chamber in which are located two gear-type pump pinions 111,112, the pinion 112 being connected to and driven by the pump input shaft 33. The hopper and pump extend transversely across the full width of the conveyor 10, and the casing as illustrated in FIG. 8 has two downturned grooves 113 in its lower surface acting as supporting brackets to engage horizontal supporting rails (not shown) over the conveyor. An undercut formation 114 positioned immediately below the pump chamber is adapted to receive a variety of alternative discharge nozzles for use with the different types of materials to be dispensed, and the complete hopper and pump unit is conveniently removable from the remainder of the apparatus.

The dispenser 111 is specially designed to handle mixtures containing raisins, without damaging the fruit. One of the pump pinions 1 11 has a cross section which is a normal conventional involute gear profile, with for example eight teeth extending lengthwise along the full length of the member. The other rotary member 112 differs from the first member in that the tips 120 of all the teeth are relieved (i.e. the tips are removed), over the whole length of the member, apart from small portions 121 at each end. In this particular example the overall diameter of each pinion member 111,112, is approximately 2 inches, and the radial dimension of the removed or relieved part 120 of each tooth may be approximately inch. Since in normal involute gear teeth there is usually a gap of for example 16inch between the tip of one tooth and the base of the gap between the teeth in the other rotary member, this relieving 120 combines to afford a gap or clearance of say /4inch. In addition alternate teeth 122 on the second rotary member are fully removed down to the base circle, apart from the short portion 121 of each tooth at each end. It will thus be seen that the second rotary member 112 has complete involute profiles on the short sections 121 at each end, sufficient to mate with and be driven by the other rotary member 111.

The fact that the tips 120 of all the teeth on the second rotary member are relieved does not in itself destroy the effectiveness of the seal between the two rotary members since in any involute gear pair the I contact is formed by the rolling flanks of the teeth, not

their tips. The fact that alternate gear teeth 122 are removed from the second rotary member does of course destroy any possible seal between these particular teeth and the opposing teeth of the first rotaty member 111, but it is found in practice that an effective seal will be formed by the remaining teeth so that a direct return passage from the outlet to the inlet side of the pump between the two rotary members is avoided. Thus even though a certain quantity of material may be carried back from the outlet side towards the inlet side the pump will still be capable of maintaining a discharge pressure. Any small bodies such as raisins which may be carried around between the teeth will be returned towards the inlet side of the pump without risk of serious damage, being located either in the gaps between the relieved tips of the teeth and the opposing parts of the other rotary member, or in the relatively large chambers created by the elimination of alternate teeth on the second rotary member.

The lower part of the hopper wall above the pump is also preferably relieved on one side at 125, adjacent that one of the rotary members which is not relieved,

and so provides a tapering clearance at the point where the material enters the pumping passage, thus reducing any tendency for bodies such as raisins to be crushed at this point.

We claim:

1. Apparatus for dispensing a liquid or semi-solid material such as a paste, batter or pastry-cook's filling, comprising a movable conveyor for carrying a plurality of trays each of which is to be supplied with the material in succession, a substantially stationary dispensing container positioned above said conveyor, said container being provided with a nozzle having a discharge slot directly above and equal in width to the width of each of said trays for dispensing said material into each of said trays to substantially completely fill each of said trays to a desired depth in succession as said trays are moved past said nozzle, a rotary pump, first means for driving said rotary pump in one direction to dispense the material from the container through the discharge slot onto a tray as said tray moves past said discharge slot, means for stopping the pump to interrupt the dispensing of said material, second means for driving the pump momentarily in the reverse direction immediately after its stoppage, synchronized means for jogging" the conveyor to cause the tray to move generally vertically toward and away from the nozzle during the period when the pump drive is stopped and driven in the reverse direction, and means for automatically interrupting the reverse drive to the pump after a predetermined short interval, said interval being determined by a predetermined movement of said pump in its said reverse direction.

2. Apparatus according to claim 1, in which the first and second means for driving the pump in opposing directions respectively comprise two contrarotating drive elements connected to drive the pump in parallel through clutches, and control means for selectively controlling the engagement and disengagement of said clutches.

3. Apparatus according to claim 1, in which the synchronized means for jogging the conveyor is interconnected with and actuated by said second means for driving the pump in the reverse direction.

4. Apparatus for delivering a viscous, pasty, or semisolid material such as a food paste or batter onto an elongated substantially rectangular tray having a pair of comparatively narrow end walls and a pair of comparatively elongated side walls, said apparatus being operative to fill said tray completely, including the interior corners thereof, between the respective end walls and side walls of said tray to a constant thickness automatically, said apparatus including dispensing means for discharging the material onto the tray, said dispenser including a discharge slot having a width equal to the width of said tray between its side walls and extending across said tray in a direction transverse to the direction of elongation of said tray, a conveyor for selectively carrying the tray in the direction of its elongation past said dispenser, a stop device extending into engagement with one of the tray end walls to locate the tray initially at a stationary start position on said conveyor, said discharge slot of said dispenser being 10- cated above said tray at a position facing the corner between the bottom of said tray and said one of said end walls when said tray is in its said start position, first control means for automatically withdrawing the stop device so that the tray can thereafter advance along said conveyor past the dispensing means, second control means for actuating the dispensing means to cause discharge of the material for an appreciable time interval while the tray moves past the dispensing means, and time delay means arranged to initiate operation of said first control means at a precise interval of time subsequent to initiation of operation of said second control means thereby to delay the withdrawal of the stop demomentarily at the end of each discharge operation.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. ,7 ,4 D d January 1, 1974 Inventor(s) Thomas Edward Cartwright and John Clifford Wightman -It is certified that error appears in the 'above-identified patent and that said Letters Patent are hereby corrected as shown below:

In the Heading:

[73] correct the name of the assignee as follows:

change "Jones D. Ayers and Company Limited" to D. Ayres Jones and Company Limited Signed and sealed this 23rd day of July 197A.

(SEAL) Attest:

MCCOY M. GIBSON, JR. C. MARSHALL DANN Attesting Officer Commissioner of Patents

Claims

1. Apparatus for dispensing a liquid or semi-solid material such as a paste, batter or pastry-cook''s filling, comprising a movable conveyor for carrying a plurality of trays each of which is to be supplied with the material in succession, a substantially stationary dispensing container positioned above said conveyor, said container being provided with a nozzle having a discharge slot directly above and equal in width to the width of each of said trays for dispensing said material into each of said trays to substantially completely fill each of said trays to a desired depth in succession as said trays are moved past said nozzle, a rotary pump, first means for driving said rotary pump in one direction to dispense the material from the container through the discharge slot onto a tray as said tray moves past said discharge slot, means for stopping the pump to interrupt the dispensing of said material, second means for driving the pump momentarily in the reverse direction immediately after its stoppage, synchronized means for ''''jogging'''' the conveyor to cause the tray to move generally vertically toward and away from the nozzle during the period when the pump drive is stopped and driven in the reverse direction, and means for automatically interrupting the reverse drive to the pump after a predetermined short interval, said interval being determined by a predetermined movement of said pump in its said reverse direction.

3. Apparatus according to claim 1, in which the synchronized means for ''''jogging'''' the conveyor is interconnected with and actuated by said second means for driving the pump in the reverse direction.

4. Apparatus for delivering a viscous, pasty, or semi-solid material such as a food paste or batter onto an elongated substantially rectangular tray having a pair of comparatively narrow end walls and a pair of comparatively elongated side walls, said apparatus being operative to fill said tray completely, including the interior corners thereof, between the respective end walls and side walls of said tray to a constant thickness automatically, said apparatus including dispensing means for discharging the material onto the tray, said dispenser including a discharge slot having a width equal to the width of said tray between its side walls and extending across said tray in a direction transverse to the direction of elongation of said tray, a conveyor for selectively carrying the tray in the direction of its elongation past said dispenser, a stop device extending into engagement with one of the tray end walls to locate the tray initially at a stationary start position on said conveyor, said discharge slot of said dispenser being located above said tray at a position facing the corner between the bottom of said tray and said one of said end walls when said tray is in its said start position, first control means for automatically withdrawing the stop device so that the tray can thereafter advance along said conveyor past the dispensing means, second control means for actuating the dispensing means to cause discharge of the material for an appreciable time interval while the tray moves past the dispensing means, and time delay means arranged to initiate operation of said first control means at a precise interval of time subsequent to initiation of operation of said second control means thereby to delay the withdrawal of the stop device until after the dispensing means has started to operate and has filled material into said corner and to a desired depth between said side walls so that the material is thereafter spread substantially uniformly at said desired depth along the remaining length of said tray as said tray advances along said conveyor.

5. Apparatus according to claim 4, in which the time delay factor of the delay means is adjustable.

6. Apparatus according to claim 4, in combination with drive means for reversing the dispensing means momentarily at the end of each discharge operation.