GB2046569A - Finishing vat for cheese making - Google Patents

Abstract

An enclosed finishing vat for cheese making. The vat 1 has a generally oval configuration and an agitator unit 12 is mounted for reciprocating movement on a frame 13 above the vat and includes a vertical drive shaft 16 that extends through a slot 17 in the top 4 of the vat. The lower end of the drive shaft carries a rotatable support arm 28 and at each end of the arm both a stirring paddle 34 and an unloading paddle 39 are pivotally mounted. The stirring paddle and unloading paddle extend in opposite directions from the respective end of the arm. In operation, the agitator unit reciprocates along the length of the vat, and the arm is rotated such that the stirring paddles 34 lead in the direction of rotation and stir the curd, while the unloading paddles 39 trail and float on the curd. To unload the curd from the vat, a discharge opening 42 in the bottom of the vat is opened and the direction of rotation of the arm is reversed, whereby the unloading paddles lead in the direction of rotation and scrape along the bottom 3 of the vat and deliver the curd through the discharge opening 42. <IMAGE>

Description

SPECIFICATION Finishing vat for cheese making In the conventional cheese making process for producing cheddar, colby or stirred curd cheese1 the curd and whey are transferred from the cheesemaking vat to a finishing vat where the curd is slowly agitated and the whey is drawn off. Subsequently, the cheddar type curd is milled and, in all cases, the moist curd is agitated by forking paddles which travel the length of the vat on a reciprocating carriage. In the past, the curd was removed from the vat by manual shoveling and placed in hoops. Recently, as disclosed in United States Patent No. 3 853 241, finishing vats have been constructed with an open end enclosed by a removable or hinged door. With a vat of this type, the curd, instead of being shoveled out of the vat, is pushed out of the open door into a series of hoops or onto a conveyor system.

The conventional finishing vat has an open top, and thus, the cheese curd is subjected to contamination from the environment. In addition, due to the open top, there is a certain amount of evaporation that occurs unless the finishing vat is equipped with a water heated jacket to maintain the curd in a warm state and prevent evaporation.

In the past, separate implements have been utilized for the stirring and for the removal of the curd from the finishing vat. The normal stirring implements take the form of small fork-like paddles or rakes, and, to discharge the curd, the stirring paddles must be removed and replaced by pusher blades which extend the width of the vat. The removal of the stirring paddles and replacement with the pusher blades requires considerable labour and results in a certain amount of downtime for the vat.

The invention relates to an improved finishing vat for cheesemaking. A vat according to a principal aspect of the present invention comprises a vat having a bottom wall and a side wall, a vertical shaft disposed within the vat, a frame secured to the shaft and disposed within the vat, drive means to rotate the shaft and the frame in a first direction, and a paddle pivotally connected for floating vertical movement to the frame and disposed to ride along the bottom wall when the shaft is rotated, said paddle having a generally concave curd engaging edge facing in said direction.

According to a preferred aspect of the invention, the bottom wall of the vat has an elongated discharge opening disposed generally parallel to straight side sections, said discharge opening having a length such that the path of travel of said paddle will continuously intersect said opening during reciprocating movement of said agitator unit.

According to another aspect of the invention, a particularly preferred vat has a generally flat bottom wall, and a side wall, an agitator unit mounted to move in a reciprocating path relative to the vat to agitate the cheese curd in the vat, said agitator unit including a vertical drive shaft and reversible drive means to selectively rotate the shaft in a stirring direction and an opposite unloading direction, an arm secured to the lower end of the shaft and disposed within the vat, a stirring paddle pivotally connected for floating vertical movement to the arm, said stirring paddle having a stirring edge facing in said stirring direction and disposed to stir the curd as the shaft is rotated in said stirring direction, a discharge outlet in the bottom wall of the vat, and an unloading paddle pivotally connected for free vertical movement to the arm, said unloading paddle having an unloading edge facing in said unloading direction and disposed to ride along the bottom wall of the vat to deliver the curd to the discharge outlet when the shaft is rotated in the unloading direction.

Moreover the vat is preferably enclosed by a top wall.

With this preferred vat, during the cheese making operation, the agitator unit is reciprocated along the length of the vat, and the arm is rotated in a direction such that the stirring paddles lead in the direction of rotation and stir the curd, while the unloading paddles trail and float on the curd.

To unload the curd, a discharge opening in the bottom wall is opened and the direction of rotation of the arm is reversed, so that the unloading paddles lead in the direction of rotation and scrape along the bottom wall and deliver the curd to the discharge opening.

As the preferred finishing vat is totally enclosed, contamination of the curd is virtually eliminated, and a more sanitary operation is achieved. Due to the elimination of contamination, better quality control can be obtained.

As the vat is closed, evaporation is reduced and the curd will remain at a relatively constant temperature, thus eliminating the need for auxiliary heating, such as a water jacket, which is normally associated with the conventional finishing vat. Further, drying of the curd on the side walls of the vat is minimized.

As both the stirring paddles and the unloading paddles are permanently attached to the support arm, there is no necessity for removal and replacement of implements during the cheese making operation.

In addition, the vat, because it is totally enclosed, can be readily cleaned-in-place, including the implements attached to the arm.

Other objects and advantages will appear in the course of the following description.

The drawings illustrate the best mode presently contemplated of carrying out the invention. In the drawings: Figure lisa side elevation of the enclosed finishing vat of the invention with parts broken away; Figure 2 is an end view of the vat; Figure 3 is a top plan view of the vat with parts broken away in section; Figure 4 is an enlarged section taken along line 4-4 ofFigure1; Figure 5 is an enlarged view taken along line 5-5 of Figure 3; Figure 6 is an enlarged section taken along line 6-6 of Figure 3 and showing the mechanism for enclosing the discharge opening; Figure 7 is an enlarged fragmentary top plan view of the arm carrying the stirring paddle and the unloading paddle; and Figure 8 is a side elevation of the structure shown in Figure 7.

The drawings illustrate an enclosed finishing vat 1 for making cheese, such as cheddar, colby or stirred curd, which includes a generally oval side wall 2, comprising two generally straight side sections and two curved end sections, a flat bottom wall 3, and a dome-shaped top 4. The vat is supported on a series of legs 5 from the foundation or ground.

A whey tank 6 is located at one end of the vat, and the bottom wall 3 slopes in a direction toward the whey tank to permit the whey to drain to the tank. A screen 7 is positioned across the entrance to the whey tank to prevent the curds from entering the tank. Located in the lower end of the tank 6 is a drain 8.

To facilitate draining of the whey toward the whey tank 6, a trough 9 is formed in the bottom wall 3 and extends longitudinally of the vat. As best shown in Figure 6, the upper end of the trough is enclosed by a screen 10 which prevents the curds from entering the trough.

The curds and whey are introduced into the vat 1 through an inlet conduit 11 located in the top wall 4.

The curds in the vat are stirred by an agitator unit 12 which travels in a reciprocating path along the length of the vat. The agitator unit 12 is supported on a framework which includes a pair of longitudinal beams 13 that are supported from the top 4 through vertical legs 14. A motor and gear transmission unit 15 is mounted for travel in a reciprocating path on the longitudinal beams, and the unit 15 serves to drive a vertical shaft 16 which extends through a slot 17 in the top wall 4. As best shown in Figure 3, the slot 17 is bordered by an upstanding flange 18 and the motor and gear unit 15 carries an elongated shield 19 having downwardly extending side flanges 20 which are located outwardly of the flanges 18 bordering slot 17. The mating flanges 18 and 20 provide a closure for the slot as the motor and gear unit 15 moves in its reciprocating path of travel.

To drive the agitator unit 12 in its reciprocating path, drive shafts 21 extend outwards from opposite sides of the unit 15 and carry gears 22, which engage racks 23 mounted on the longitudinal beams 13. The motor and gear unit 15 is guided in movement by rollers 24 mounted on shafts 25 that project laterally from opposite sides of unit 15, and the rollers ride on the lower surface of the beams 13. Lateral restraint is provided by rollers 26 carried by brackets 27 which ride against the side surfaces of the respective beams. This reciprocating drive for the agitator unit is in itself conventional, and forms no part of the present invention.

The lower end of the vertical drive shaft 16 carries a rotating, horizontal cross arm 28, and both a stir ring paddle assembly 29 and an unloading paddle assembly 30 are mounted on each end of the rotat ing arm 28.

To connect the stirring paddle assembly 29 and the unloading paddle assembly 30 to the arm 28, a vertical support rod 31 extends downwards from the respective end of the arm 28 and a horizontal bar 32 is attached to the lower end of the support 31 and extends laterally of the arm. The stirring paddle assembly 29 includes a curved arm 33 that is pivotally connected to the end of the bar 32 and a stirring paddle 34 is mounted on the end of the arm 33. As shown in Figures 7 and 8, each stirring paddle 34 is generally T-shaped having a stem portion 35 and a head 36 with a sharpened lower edge 37. The edge 37 is adapted to ride along the bottom wall 3 of the vat as the arm 28 is rotated in the stirring direction, so that the paddle 34 will stir and agitate the curd.

The pivotal connection with bar 32 enables the paddle 34 to float in a vertical direction.

Each unloading paddle assembly 30 includes an arm 38 which is pivoted to bar 32 and an unloading paddle 39 is attached to the end of the arm. The paddle 39 has a stem 40 and a pair of legs 41 extend outwardly from the stem at an obtuse angle to each other, as shown in Figure 7, to provide a generally concave configuration for the paddle as seen in plan.

The arms 33 and 38, which carry the stirring paddle 34 and the unloading paddle 39 are located, as seen in plan (Figure 7), at an angle of about 80 with respect to the axis of the arm 28 so that the paddles will not engage the side wall when the arm 28 is rotated at the end of the stroke of travel of the agitator unit.

In addition to the stirring paddles 34 and unloading paddles 29, a series of hinged rod rakes 43 are pivotally mounted on the arm 28 and during rotation serve to rake through and break up the curds and maintain the curds in a granular condition.

During the stirring operation, the agitator unit 12 is moved in a reciprocating path of travel along the length of the vat and simultaneously the arm 28 is rotated about the axis of the drive shaft 16. The rotation is in the direction of the solid arrow in Figure 3, and the stirring paddles 34 lead in the direction of rotation and scrape along the bottom of the vat to stir and agitate the curd, while the unloading paddles 39 will trail and float on the curd due to the pivotal connection of the arms 38 with the horizontal bar 32. This free floating action also tends to break up clumps of curd. During the stirring, residual whey will be expelled from the curds and will drain into trough 9.

When it is desired to unload the curds from the vat, the direction of rotation of the drive shaft 16 is reversed, as shown by the broken-line arrow in Figure 3, so that the unloading paddles 39 lead in the direction of rotation and scrape along the bottom wall 3 and deliver the curd to a discharge opening 42 located in the bottom wall. This discharge opening 42 is generally parallel to the opposite straight side sections of the side wall 2, and has a length such that the path of travel of the unloading paddles 39 will continuously intersect the discharge opening during reciprocating movement of the agitator unit.

As best illustrated in Figure 5, the discharge opening 42 is bordered by a downwardly extending flange and a pivoted door 44 is adapted to close the discharge opening 42. The door44 is composed of an upper resilient pad 45, which bears against the lower edge of the flange to provide a seal, and a stainless steel backing plate 46.

The backing plate 46 is carried by an elongated vertical plate 47 (Figure 4) which has a length greater than the length of the discharge slot 42. The ends of the plate 47 are pivotally connected to brackets 48 in turn are pivoted to lugs 49 that extend downwards from the bottom surface 3 of the vat.

The door is adapted to be moved between a closed and an open position by a hydraulic cylinder unit 50, best shown in Figure 4, which includes a cylinder 51 attached through lugs 52 to the bottom wall 3 of the vat, and a piston rod 53 which is mounted for sliding movement within the cylinder. The outer end of each piston rod is connected to the pivot between the plate 47 and a lug 54, the lower end of which is pivoted to the respective end wall 55 of a hopper 56.

By extending the piston rod, the plate 47 and the door 44 will be pivoted downwardly to a generally vertical open position, as illustrated by the phantom lines in Figure 4, to permit the curd to be discharged through the discharge slot 42.

The door and mounting mechanism is contained within the hopper 56 which is secured to the lower surface of or the bottom wall 3. Mounted for rotation within the hopper is an auger or screw conveyor 57 having a shaft 58 which extends through the end wall 55 of the hopper and is driven by a motor 59. A discharge conduit 60 is connected to the opposite end of the hopper. The auger 57 acts to convey the curd to the discharge conduit 60 where it falls by gravity into a pneumatic blower unit 61 that conveys the curd to the desired location.

As the finishing vat in this embodiment is totally enclosed, contamination of the product is virtually eliminated and a more sanitary operation results.

The closed vat also reduces evaporation, and maintains the curd at a relatively constant temperature so that auxiliary heating in the form of a water jacket is not required with the finishing vat of the invention.

Both the stirring paddles and the unloader paddles are permanently fixed to the rotating arm, and the stirring and unloading is accomplished by merely reversing rotation of the drive shaft. This eliminates the necessity of removing and replacing implements for the stirring and unloading operations as is necessary in conventional finishing vats. This reduces the downtime for the vat.

Because the vat is totally enclosed, it can readily be cleaned-in-place, including the stirring and unloading paddles which are attached to the rotating arm.

Claims (14)

1. A finishing vat for cheese making, comprising a vat having a bottom wall and a side wall, a vertical shaft disposed within the'vat, a frame secured to the shaft and disposed within the vat, drive means to' rotate the shaft and the frame in a first direction, and a paddle pivotally connected for floating vertical movement to the frame and disposed to ride along the bottom wall when the shaft is rotated, said paddle having a generally concave curd engaging edge facing in said direction.

2. The vat of claim 1, wherein the central portion of said edge is located to the rear from a plane passing through the outer extremities of said edge.

3. A finishing vat for cheese making, comprising an elongated vat having a generally flat bottom wall and a side wall, said side wall having generally straight side sections and curved end sections, an agitator unit mounted to move in a reciprocating path in the vat to agitate cheese curds in the vat, said agitator unit including a vertical shaft and drive means to rotate the shaft in a first direction, a frame secured to the lower end of the shaft and disposed within the vat, and a paddle pivotally connected to the frame for free vertical movement and disposed to ride along the bottom wall of the va) as the shaft is rotated, said bottom wall having an elongated discharge opening disposed generally parallel to said side sections, said discharge opening having a length such that the path of travel of said paddle will continuously intersect said opening during reciprocating movement of said agitator unit.

4. The vat of claim 3, wherein the paddle is provided with an elongated curd engaging surface facing in said direction, the central portion ofthecurd engaging surface being disposed to the rear, with respect to said direction, from a plane extending through the outer extremities of said surface.

5. A finishing vat for cheese making, comprising a vat having a generally flat bottom wall, and a side wall, an agitator unit mounted to move in a reciprocating path relative to the vat to agitate the cheese curd in the vat, said agitator unit including a vertical drive shaft and reversible drive means to selectively rotate the shaft in a stirring direction and an opposite unloading direction, an arm secured to the lower end of the shaft and disposed within the vat, a stirring paddle pivotally connected for floating vertical movement to the arm, said stirring paddle having a stirring edge facing in said stirring direction and disposed to stir the curd as the shaft is rotated in said stirring direction, a discharge outlet in the bottom wall of the vat, and an unloading paddle pivotally connected for free vertical movement to the arm, said unloading paddle having an unloading edge facing in said unloading direction and disposed to ride along the bottom wall of the vat to deliver the curd to the discharge outlet when the shaft is rotated in the unloading direction.

6. The vat of claim 5, including a doorto enclose the discharge outlet and movable between a closed position and an open position, and means to move the door from the closed to the open position.

7. The vat of claim 6, and including a hopper mounted on the lower surface of the bottom wall of the vat and enclosing said door, the curd discharged through the door being received in said hopper.

8. The vat of claim 7, and including a conveyor in the hopper for moving the curd to a collection site.

9. The vat of any of claims 5 to 8, wherein said vat is enclosed by a top wall, and said reversible drive means is located on the outside of the vat, and said top wall is provided with a slot to receive said vertical drive shaft.

10. The vat of claim 9, and including a shield attached to the reversible drive means to enclose the slot as the agitator unit moves in its reciprocating path.

11. The vat of any of claims 5 to 10, wherein the central portion of the arm is connected to said drive shaft and both a stirring paddle and an unloading paddle are pivotally mounted on each end of the arm and extend laterally of said end of the arm in opposite directions.

12. The vat of any of claims 5 to 11, wherein the unloading edge of the unloading paddle has a generally concave shape in plan.

13. The vat of claim 12, wherein the unloading edge of the unloading paddle is composed of a pair of sections disposed at an obtuse angle with respect to each other.

14. The vat of claim 5, substantially as described with reference to the accompanying drawings.