JPH03158682A - Refrigerating machine - Google Patents

Abstract

PURPOSE: To prevent the contraction at changing point, by permitting the relative movement in lengthwise direction by the necessary quantity allowable for increasing the generated distance while the outer periphery of a conveyor belt is changed into curved shape from the straight track. CONSTITUTION: A conveyor belt corresponds to the straight track and spiral track sections, and its shape changes as it enters the spiral track section. The conveyor belt 22 is provided with a plurality of rods 52 extending in a right- angle direction of belt, and the inner end parts of the rods 52 are fitted pivotally to links 62 made of wire material. The adjacent links 62 move pivotally and are displaced in angular direction, so that the inner edge of the belt is fitted to the circular or spiral track. The outer end parts 60 of the rods 52 are connected with each other by means of a series of links 64 with slots, and the expansion of the outer peripheral parts 56 of the belt can be permitted. Further, a plurality of bending wire members 68 form the upper surface 70 for supporting products.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application] The present invention relates to conveyor belts for use in refrigerators, and in particular to conveyor belts for use in refrigeration machines, particularly at the transition between a straight track section and a generally helical or spiral track section. The present invention relates to an endless belt conveyor having one or more devices for preventing disturbance of the food being conveyed on the conveyor belt at the transition point.

BACKGROUND OF THE INVENTION Several types of conveyor belt systems are currently used to convey food or other products through refrigerators, which typically include an insulated closed chamber to maintain a temperature below ambient temperature. In order to provide the longest track in an insulated closed chamber of minimum volume and external area, the conveyor belt conveying the product through the closed chamber should be provided with one or more helical tracks, or in the industry known as "spiral" tracks. It is often the case that what is called is passed through. Thus, the conveyor belt changes its shape, particularly along its inner edge and its outer edge, at the point where the straight track section enters the helical track section. To date, conveyor belts have either been retracted along their inner edges, or each of their inner and outer edges have been retracted and raised one way.

A number of problems arise when a conveyor belt carrying relatively delicate products, such as meat pies, shrinks. For example, meat pies have been found to adhere to the underside of the conveyor belt at the point of entry into the freezer compartment.

Subsequent shrinkage of the conveyor belt often damages or twists the bottom of the pie in contact with the conveyor belt. Therefore, it is desirable to reduce or eliminate the aforementioned kinks and surface flaws, especially since this often causes the frozen food to be rejected.

Other problems arise due to belt shrinkage. For example, when a conveyor belt contracts, it can cause adjacent products to contact each other and become twisted. To help reduce such contact, food items loaded upstream of the helical portion are often spaced far enough apart to ensure that such contact does not occur at the point where the belt spirals. However, this reduces the capacity of the refrigerator by significantly reducing the product loading density on the conveyor belt, and the liquid refrigerant is injected onto the products carried on the belt in the straight feed section. This creates other potential problems in the refrigerator. Liquid refrigerant or C
For the most efficient use of the cooling properties of O2 dry ice, it is believed to be important to allow the latent heat absorbed to convert the refrigerant into a vapor to be directly removed from the surface of the product being frozen. Therefore, if spacing between products is required to allow for a reduction in surface area at the transition point, it is not possible to completely cover the belt, so excess refrigerant is preferably removed from the product being frozen. Rather than absorbing latent heat directly, it must be absorbed from the circulating steam.

To reduce the problem of food kinking and surface scratches at conveyor belt transition points, the product can be strengthened by localized freezing concentrated at the bottom of the product. Using this technique, the bottom surface of the food product is made rigid enough to cover deposits at the point of contact with the conveyor belt as the belt retracts at the point of transition into the spiral section. However, making such preparations from the beginning requires expensive additional equipment and consumes valuable floor space at the entrance to the refrigerator.

Other problems are experienced at transition points where the conveyor belt partially collapses due to its helical shape. Typically, the transition point is located immediately downstream of a product loading station where the straight section of the conveyor belt is loaded with product. Typically, products are loaded onto a conveyor belt from individual loading belts, the speed of which must be matched to the speed of the conveyor belt to space the food products at desired intervals along the conveyor belt. Currently, the most satisfactory method of matching the speed of the loading belt and the conveyor belt is by observing the spacing between product units at a point downstream of the loading belt. Although this method is generally satisfactory for continuous straight or "tunnel-type" conveyors, direct visual observation is typically extremely difficult for refrigerators with spiral track sections. Therefore, the need to adjust the product spacing is indicated only after the product units come out of the closed chamber of the refrigerator. As such, complete loading of the conveyor belt often has to be delayed until several sample product units have completed their entire trajectory through the closed chamber of the refrigerator, and sometimes until satisfactory. It is necessary to repeat the interval adjustment several times.

[Problems to be Solved by the Invention] An object of the present invention is to provide a method that has zero point of change between the straight line portion and the spiral trajectory portion, but does not contract at one point of change.
The purpose of the present invention is to provide a conveyor belt for use in refrigerators.

Another object of the invention is to provide a conveyor belt in which the belt only widens in that it changes shape as it passes from a straight section to a helical track section.

SUMMARY OF THE INVENTION These and other objects of the present invention will become apparent upon consideration of the following description in conjunction with the accompanying drawings. Provided in a refrigerator that includes an insulated closed chamber.

The refrigerator further includes a conveyor belt for conveying a product, such as a food product, from an inlet to an outlet of the enclosed chamber through the controlled environment within the enclosed chamber.

Means is provided for driving the belt conveyor along an initially straight trajectory to a transition point where the conveyor belt changes shape from a first configuration in the straight track section to a second configuration in the spiral track section. . The conveyor belt is constructed such that it only widens longitudinally at the transition point. In particular, the conveyor belt only widens longitudinally at the outer edges of the conveyor belt as it transitions from a straight track section to a helical track section. Cooling means are provided within the enclosed chamber to establish a temperature sufficiently low to remove heat from the product being conveyed along the conveyor belt.

In one embodiment, a plurality of transverse rods extend between the inner and outer transverse edges of the conveyor belt. The inner ends of said rods are interconnected by a first link at a point adjacent to the inner lateral edge of the conveyor belt, particularly at the transition point where the conveyor belt changes shape from a straight track to a helical track configuration. Substantially no provision is made for relative longitudinal movement at. However, the interconnections between the links and rods along the outer edge of the conveyor belt have a relative longitudinal length sufficient to accommodate the increase in distance that occurs during the transition of the belt from a straight track to a curved track configuration. Allows directional movement.

According to another aspect of the invention, a conveyor belt includes a fabric-like arrangement of bent wire members, each of said bent wire members being wrapped around a pair of transverse rods and spread out. Creates an upper product support surface. According to another aspect of the invention, the wire members are formed in a staggered manner with alternating upper and lower members. In one embodiment, the lower member of the wire member is folded upwardly at a central location to form leading and trailing pockets of generally equal size, and as the belt changes from a straight to a curved configuration, each pocket Limit the relative momentum of the transverse rods received at .

Identical elements in the figures are designated by the same reference numerals.

[Example] Referring to the drawings for illustrative purposes and not by way of limitation, the drawings are generally 1
The refrigerator, designated 0, includes an insulated sealed chamber 12 having an inner cavity 14 kept below ambient temperature by a refrigeration system, not shown.

An inlet duct 16 is provided for connection to the refrigeration system,
The duct is suitable for introducing a refrigeration medium, such as frozen air, into the cavity 14 in order to cool or freeze the product introduced therein. A plurality of fans 18 circulate cooling medium within cavity 14 . As shown, fan 18
directs the refrigerated medium across the surface of a conveyor belt, indicated generally at 22, to provide a heat transfer rate sufficient to cool or freeze the product carried thereon as it is conveyed through the refrigerator. are employed to provide.

The closed chamber 12 includes a housing 24 having an opening 26 through which the products loaded on the conveyor belt enter the freezing chamber IO. Within the cavity 14 is the structure of U.S. Pat.
Cylindrical drive drum 28 of the type described in No. 8.659
is installed. The drive drum 28 is driven by a motor (not shown) to rotate around the central axis of the drum. The drum engages the inner edge of the conveyor belt 22 to drive the conveyor belt along the trajectory shown in FIG. The outer framework 30 has legs 32 supported by the floor 34 of the enclosed chamber and has a number of generally radially oriented braces 36 connected to the cylindrical structure at the inner end.
including.

The braces 36 extend below the conveyor belt 22 and provide support for the belt, particularly at the outer edges of the belt.

As shown in FIG. 1, the conveyor belt 22 has a first straight track section 40 in which the belt is connected to the housing 24.
, and proceed in the direction of arrow 42. Preferably, a restraining means, such as a C-shaped channel (FIG. 2A), is provided along the outer edge of the conveyor belt 22 in the straight section. The conveyor belt 22 then enters a helical track section 44 where a series of wraps or layers of the conveyor belt are connected to braces 36 that support the weight of the conveyor belt and the product loaded thereon, That is, it is supported by a cylindrical structure 28 that supports against lateral movements.

Upon exiting the helical track portion 44, the conveyor belt 22 approaches the exit opening 48 of the closed chamber L2 and through said opening,
The products discharged from the conveyor belt 22 can be taken out from the refrigerator IO. Although not shown, for example, a chute can be provided below the rollers 50 over which the conveyor belt 22 passes.

The conveyor belt is looped through a series of rollers 94 disposed along the intermediate track section of the inlet housing 24.
Return to Roller 96 is located upstream of housing 24;
The belt 22 is oriented to pass along an initial straight track section 40. In said track section 40 the products can conveniently be loaded onto the conveyor belt. roller 96
is attached to the shaft 98. The shaft 98 is driven by a motor to drive the conveyor belt along its linear, helical and intermediate track portions. The drive roller 96 described above is described in U.S. Pat. No. 3,467,239.
A sprocket foil having teeth for engaging the inner end portion 58 of the rod 52 within the link 82 (see FIG. 2) or the link 62 may be incorporated at its inner edge in the manner described in the above.

Other suitable drive means may be used to engage conveyor belt 22 to drive it along its trajectory of motion. See, for example, U.S. Pat. Nos. 3,938,651 and 4.5, which are incorporated herein by reference.
An endless drive belt may be disposed in contact with the helical bottom layer of the conveyor belt in the manner shown and described in No. 65,282. Furthermore, the endless drive belt may be extended to also engage at least a portion of the cotton track of the conveyor belt, and this is contemplated in the present invention.

2 and 3 show a conveyor belt 2 corresponding to a straight track section and a spiral track section, respectively, of the conveyor belt.
2 shows two types of forms. With further reference to FIGS. 3 through 14, conveyor belt 22, when constructed in accordance with the principles of the present invention, simply expands as it enters a helical track portion 44 that rotates and bends in a horizontal plane. Only. Regarding the change in the shape of the conveyor belt that occurs as it leaves the straight track section shown in Fig. 2 and enters the spiral track section shown in Fig. 3,
This is carefully controlled by the construction of the conveyor belt, described below with reference to FIGS. 2-14.

Now, referring to FIGS. 2 and 3, the conveyor belt 2
2 is preferably composed of a plurality of rods 52 extending generally in a direction perpendicular to the linear trajectory of the conveyor belt. Said rod 52 has lateral inner and outer edges 54.5
6, the inner edge 54 of which is located in the radially inner part of the conveyor belt in the helical track section.

Transverse edges 54,56 of the conveyor belt are located in the radially inner and radially outer parts of the conveyor belt, which are wound along the helical track.

Conveyor belt 22 includes a plurality of rods 52 adjacent the inner and outer edges of the belt and defining inner and outer edge portions 58,60. The inner ends of the rods 52 are pivotally connected to each other by links 62 formed from flat wire material. Figures 2 and 3 are plan views of a portion of the conveyor belt.
In the figure, it is located in a relatively flat, but tilted part of the spiral orbit.

Comparing FIGS. 2 and 3, adjacent links 62 can pivot and be angularly offset from each other;
It can be seen that the angular offset occurs in the plane of the belt, allowing the inner edge portion of the belt to conform to a circular or helical trajectory.

The outer ends 60 of the rods 52 are interconnected by a series of slotted links 64, resembling bars or flat plates. It can be seen that the links 64 allow the outer edges 56 of the belts 2.2 to widen.

A plurality of folded wire members 68 form an enlarged product-supporting top surface 70, which top surface can be used to support products, whether the belt portion supporting the food product is located on a straight track or a helical track portion of the conveyor belt. Regardless of the shape of the belt, it is preferred that the holes be perforated so that the cooling medium flows continuously. In a preferred embodiment, each wire member 68 is wrapped around a pair of rods 52 to form an upper surface 70, which provides other advantages that may be noted below. The pair of rods, together with the folded wire wrapped around them, form an area of the conveyor belt as shown. Each rod is common to a pair of adjacent belt regions and, in combination with links located at the inner and outer ends of the conveyor belt, interconnects the adjacent belt regions.

Referring to FIGS. 2 and 3, the flat wire link 62 is generally U-shaped in plan view;
It has an upstream closed end 74 and a downstream free end 76.

Each link 62 includes a pair of side walls 78.80 joined to opposite ends of a front wall 74 at an upstream end. side wall 78
．． 80 has an intermediate laterally offset section 82,84 located between a forward section of shortened transverse dimension and a rearward section of enlarged dimension terminating at the open end of the link. The dimensions of the links 62 are such that the dimensions of the links 62 are partially reciprocated by a lateral offset such that the closed front end of one link is received within the dimensionally enlarged rear portion of the adjacent link. When in a shaped track section, between adjacent side walls of links that are mounted to allow some horizontal angular movement between adjacent links that are mounted on each other, as shown in Figure 3. In other words, the dimension between the inner surfaces of the side walls of the open-ended links is significantly greater than the dimension between the outer surfaces of the closed ends of the links mutually resting therein.

Referring to FIG. 11, the forward portion of sidewall 78 defines a rod-receiving opening 92 that is slightly elongated in the longitudinal direction of belt 22, ie, in the linear direction of belt movement. This elongation of aperture 92 allows for some degree of angular movement of rod 52. Referring again to FIGS. 2 and 3, the front wall 74 of one link and the link are free to allow relative angular movement between adjacent links as the link rotates about the rod 52. Sufficient clearance is provided between the laterally offset portions of the links resting on the inside thereof. This freedom of movement allows for example the roller 50 shown in FIG. 1 located near the discharge port 48, the roller 94 located downstream thereof
and the belt has a straight track section 4 at the entrance to the refrigerator.
The belt 22 is allowed to pass over a guide roller, such as roller 96, which positions the belt 22 upright as it enters zero.

Referring now to FIG. 12, the free end 7B of link 62 defines an opening 100 for receiving rod 52. As shown in FIG. As with aperture 92, aperture 100 is slightly elongated in the longitudinal direction of conveyor belt 22 to allow similar horizontal angular movement of rods received therein.
It is generally preferred that the The opening 100 of one link is connected to the opening 92 of the link placed inside the opening 100 of one link.
Once aligned, rod 5 is inserted through the mounted pair of links.
Provides passage for 2. The inner end portion 58 of the rod 52 is thickened at the end 104 to prevent the rod from slipping outwardly through the link 62. When the rod 52 is assembled into a - It is kept in a mounting relationship.

9, 10 and 14 show the outer lateral edges of the belt 22, particularly the bar link 64 that connects the upstream end 108 and the downstream end 110. As can be seen in FIGS. 2 and 3, bar links 64 each interconnect a pair of adjacent rods 52 in alternating inner and outer positions at the lateral outer edge of the conveyor belt. Preferably, the links in the medial and lateral positions are generally identical with respect to each other.

However, as will be appreciated upon consideration of the following description, the other configuration of the link forms a slot 112 at the outer edge of the conveyor belt, which slot is elongated in the longitudinal direction of the conveyor belt. Each link 64 interconnects a pair of adjacent transverse rods 52 such that each rod projects through the overlap of two adjacent links.

The towed portion of the link 64 has an opening 114 for receiving the rod.
, but this aperture more closely matches the cross-sectional shape of the rod 52 received therein. As can be seen in FIG. 2, the front and rear ends of adjacent links overlap each other, and the rear opening 114 of the upstream link is aligned with the slot 112 of the downstream link. In this manner, the outer end 60 of each rod 52 is received in two partially overlapping links, with a generally circular opening 114 in one link and the other allowing relative sliding movement therealong. It passes through the thrower l-112 which is elongated in the axial direction of the link. The outer end 60 of the rod 52 is provided with an enlarged head portion 11g that prevents the rod from being pulled out through the link even if forces are applied to the conveyor belt as the belt moves along its path through the refrigerator. ing.

9 and 1θ illustrate the alignment of bar links 64 in a straight section of the conveyor belt where each rod 52 is located adjacent the trailing end of elongated slot 112.

The conveyor belt enters the helical track section and the rod 52
As the inner ends of the rods become angularly offset horizontally with respect to each other, the inner ends of the rods only undergo relatively small angular offsets as part of the spread of the belt. The outer ends 60 of the rods 52 are allowed to splay apart significantly relative to each other by an elongated slot 112 in the outer bar link 64, which has a length several times greater than the diameter of the rod 52.

As the conveyor belt 22 exits the straight track section and enters the helical track section at the turn point, said spacing is kept generally constant by contacting the drive drum 28 along the inner edge, and thus The belt fabric extends longitudinally over its entire width. parallel direction (second
Displacement of the rods from FIG. . As the hero rod pivots from the configuration shown in FIG. 2 to the configuration shown in FIG.
8 is also pulled apart by the rod 52 during the shape change of the conveyor belt.

The folded wire member 68 has an inner end 122 and an outer end 124.
The ends can be wrapped around each rod. The folded wire member is generally trapezoidal or pie-shaped in plan view, having a small inner end dimension and widening outwardly to a relatively wide outer end. As seen in the cross-sectional views of FIGS. 4-8 and 13, the wire member 68 defines a closed inner portion;
and forms a generally flattened spiral loop including a generally horizontal upper portion 126 and curved connecting portions 128, 129.

4 through 8 illustrate a conveyor belt in a straight track portion of the conveyor belt, starting near the inner edge of the conveyor belt (see FIG. 4), where adjacent rods 52 are generally parallel to each other. outer edge (see Figure 8)
FIG. 2 is a series of cross-sectional views extending toward; As can be seen by comparing FIGS. 4 through 8, the length of the upper portion 12B of the folded wire member 68 increases toward the outer edge of the conveyor belt. Disposed on the underside of each turn of the flattened spiral is an upwardly extending recess 130 of generally constant length across the width of the conveyor belt.

Referring to the cross-sectional view of FIG. 4, taken from near the inner edge of the conveyor belt, each recess 130 is formed by a curved connecting portion 12.
It is formed by a pair of legs 132, 134 which in combination with 8 form a passage for the rod. These passages, like the passages that receive the rods of link 62, are narrowly elongated to provide clearance to accommodate angular displacement of rod 52.

The passages for receiving the rods shown in Figure 4 are shown in Figures 5 to 8.
By comparison with the previous figures, the passageways for the six pairs of rods 52 associated with each folded wire member increase in elongation from the inner end to the outer end of the conveyor belt.

As can be seen by comparing FIGS. 4 through 8, the rods 52 in the straight track portions are generally parallel to each other and are located adjacent to the legs 132 and 134 of the recess 130. Located within a pocket formed in the passageway by the bent wire member. As the conveyor belt enters the helical track section, the rod 52 is located within said pocket.
Connection 128.1 with curved rod 52 shown in FIG.
It spreads outward to the point where it contacts 29.

The free ends 122,124 of the folded wire members may be wrapped around the rod or may include a short axis portion that is received in an aperture formed in the rod 52. The folded wire member is a relatively rigid member that maintains its helically bent shape and, in particular, maintains the shape of the recess 130 irrespective of angular misalignment between adjacent rods 52 disposed on the folded wire member. Preferably, it is formed from wire material.

As previously mentioned, the folded wire member 68 is adapted to approximate a flat spiral wrap. Although the pitch between the turns has not been found to be particularly important, it is preferred that the pitch be small enough to impede air flow therebetween, but not so large as to cause the food carried thereon to fall from its support. If desired, the pitch of the folded wire members may vary between the inner and outer ends.

According to certain aspects of the invention, the recesses 130 located on each turn of the folded wire member are of similar size;
Preferably, the spacing between the legs 132, 134 of each recess corresponds to the spacing between the rods 52 when located on the straight track portion of the conveyor belt.

As will be explained in further detail, the regular spacing of the recesses 130 across the width of the conveyor belt prevents the rods from collapsing when the conveyor belt is placed in a straight track section (i.e., more closely spaced from each other than their parallel spacing). This provides some control over the spacing of the rods 52 as the endless belt exits the helical track section 44 and re-enters the straight track section just upstream of the outlet 48, and Some control over the retraction of the rod.If the belt were to be driven by contact with link 62,
When the belt re-enters the straight track, there is no reliable force acting on the rods to return them to the parallel configuration shown in Figure 2, and to ensure this return action the right side of the belt (Fig. 3) ) That is, it is preferable to apply some degree of restraint to the outer edge. For example, the ends of adjacent pairs of rods 60 may be cammed back to the defined spacing by special shoes or the like, or upper and lower guides such as the flanges of C-shaped channels 42 shown in phantom in FIG. Members or restraints are added over the short track section leading to the discharge port as well as the length of the belt track along which the belt travels in a straight line to restrain the edges of the belt against a flat plane so that the rods are generally parallel. Make it re-align.

The recess 130 further and reliably prevents any shrinkage of the conveyor belt at the transition point where the conveyor belt enters the helical track section located downstream of the straight track section. Contraction of the conveyor belt is effectively inhibited over the length of each rod that enters the transition at multiple points spaced apart along the rod. Therefore, the change in the shape of the conveyor belt during the transition from a straight track to a helical track is limited to widening only.

As will be explained in more detail below, the region of the belt approaching the transition to the downstream helical track due to actuation of the conveyor belt is such that the lateral rods of the conveyor belt are parallel to each other and are spaced apart with a minimum spacing. and has an orientation defined by bringing each rod into contact with an upright recessed portion of an adjacent folded wire section. The conveyor belt is driven by a cylindrical drive drum 28 as previously described.

As the conveyor belt enters the helical track section, the inner end of the conveyor belt contacts the drive drum and the inner edge of the conveyor belt is forced to match the radius of the surface of the drum, causing the rod 52 to wrap around its inner end. Pivot.

Collapsing of the conveyor belt, particularly on the top surface supporting the product, is effectively prevented by the spacing between the recess adjacent the inner end of the conveyor belt and the upstream and downstream openings of the U-shaped links 62. Heretofore, shrinkage has occurred at the inner edge of similar conveyor belts due to uncontrolled shrinkage forces being applied to the area of the inner edge of the conveyor belt. In the illustrated embodiment, the rod 52 pivots at regular intervals at its inner and outer ends, thereby forcing the conveyor belt to spread only along its outer edges. As previously discussed, bar links 64 allow the outer ends of rods 52 to extend a desired distance. There is usually a tendency for the inner end of the conveyor belt to contract as the conveyor belt expands along its outer edge.

However, the provision of a recess in the folded wire member and the spacing between the upstream and downstream openings of the U-shaped link 62 effectively prevents such contraction.

Therefore, the only change in the shape of the conveyor belt at the turning point is a widening of the conveyor belt; no contraction occurs. This is a significant improvement over the variety of products carried on conveyor belts. For example, meat pies loaded on top of a conveyor belt at or near room temperature at the entrance of a freezer are soft and deform quickly. To provide sufficient support for the meat pies, the conveyor belt area is sized to space typical sized pies several places apart. If the conveyor belt were to contract and compress together between the various regions under the pie, the portions of the underside of the pie would also move relative to each other. Therefore, the pie, or at least the underside of the pie, is deformed. However, it has been found that the pie does not distort as much when exposed only to the expanse of the belt conveyor area supporting it on its underside, and that upon further cooling the food product strengthens and does not distort as much. A spiral belt that only expands moves at a linear velocity equal to the linear velocity of the radially inner edge of the helical belt, which is significantly slower than a belt that only contracts, and for the same food loading capacity, the radial velocity of the belt It moves at the same speed as the outer edge. Therefore, the opportunity for cooling in the straight inlet section is significantly enhanced due to the long residence time due to the low belt speed in that section.Furthermore, if cryogen injection is desired to greatly enhance cooling in the inlet section, Closely spaced products on a belt that only spreads in the straight inlet section can make the injection of refrigerant much more efficient since a much larger portion of the surface area of the belt can be covered.

Refrigerators employing conveyors constructed according to the principles described above therefore offer significant advantages for the refrigeration of these types of products. This is because at the point where the conveyor enters the spiral trajectory, the conveyor belt only expands and does not contract.

The operation of the conveyor belt to achieve well-defined orientation in the straight track section before reaching the helical track section will now be described. The recesses 130 are preferably sized to close the spacing between the rods for portions of the conveyor belt disposed in a straight track as shown in FIG. As can be seen by considering the arrangement of the rods and folded wire members 68, two folded wire sections are associated with each rod. Of particular importance is the association of a series of indentations 130 in the folding upper member with the rod. Conveyor belts of the type described herein may experience pressure lines while passing through straight track sections. These compressive forces, when also applied to the series of indentations in the folded wire member, provide alignment forces along the length of the rod 52.

As can be readily seen by considering the folded wire members shown in FIGS. 2 and 3, a series of recesses in each folded wire member are arranged one along the forward leg 132 of each recess and a second one along the forward leg 132 of each recess. Two parallel guide surfaces are formed along the same recessed towing leg 134.

As previously discussed, the distances separated by the legs 132,134 of each recess may be of equal length, and the folded wire members may be formed to be rigid and non-deformable under typical operating conditions. Desirably, the present invention provides rod 52 with
During retraction of the conveyor belt, the rod can be economically formed from a material that can bend slightly over its entire length from the inner end to the outer end if unsupported. A series of isolated depressions and especially its legs 132.1
34 provides an effective guide surface over the length of each rod. These guide surfaces, located one adjacent the upstream edge of each folded wire member and the other adjacent the downstream edge thereof, ensure linear alignment of the central axis of each rod. As mentioned above, the guide surfaces of the bent wire members are parallel;
Advantageously, adjacent rods of the conveyor belt are spaced apart from each other to provide a preferred parallel spacing, and as will be explained in more detail below.

As the conveyor belt moves along a straight trajectory,
A series of indentations in each folded wire member in the track contacts the upstream rod to align the rod in a desired lateral direction that is generally perpendicular to the trajectory of motion of the conveyor belt. Furthermore, when seated against the upstream rod, the series of indentations in the folded wire member force the downstream rod against the downstream legs 134 by stiffening the guide surfaces of its legs. Align parallel. It has been found that directional alignment between adjacent rods is quickly and easily achieved at the point where a slight compressive force is applied to the conveyor belt.

Such compressive forces are such that the friction is sufficient to compress or "punch up" various areas of the conveyor belt when the compressive force is applied by the empty section of the conveyor belt before it is loaded with product. Can occur when forces are applied to a conveyor belt.

The invention also prevents the rod from bowing between the inner and outer ends during the spread of the conveyor belt. The inner end of the rod is controlled by a U-shaped link 62, specifically an open passage formed in the mounted pair of links. rod 52
The outer end of the bar link 64 also has a controlled amount of splay because the movement of the rod is controlled by the length of the slot formed in the bar link 64.

The bar link 64 at the outer end of the conveyor is identical in construction whether it is located in an outer or inner overlapping position. Bar links 64 limit separation of the outer ends of rods 52 as the conveyor belt widens. As previously mentioned, the folded wire member 68 is sloped when viewed in plan and its width increases from the inner end to the outer end of the folded wire member. The slope of the folded wire member is closely matched to the maximum spacing between adjacent rods. Thus, in the direction of spread of the conveyor belt, the rod 52 preferably contacts the curved connections 128, 129 of each turn of the folded wire section, as can be seen from the top view of FIG. The curved connections alternately contact each rod over the length of the rod, effectively preventing bending or arching of the rod.

As previously mentioned, the refrigerator circulates frozen steam or air therein and through each layer of the conveyor belt and over the food carried on the conveyor belt. This type of refrigerator, which freezes food by maintaining temperatures generally below 0° C., is considered to have particular advantages. By using techniques well known in the art today, the aforementioned refrigerator is readily adapted for use with liquid carbon dioxide or liquid nitrogen as the refrigeration medium to achieve freezing temperatures within the closed chamber of the refrigerator. be able to. A particular advantage of a conveyor belt constructed in accordance with the principles of the present invention is that the various moving parts are exposed to a medium of frozen, humid air that tends to form frost thereon, or of liquid nitrogen, for example. The movable parts maintain smooth and trouble-free operation even when immersed in liquid refrigerant.

Another particular advantage of a refrigerator and conveyor belt constructed in accordance with the principles of the present invention is that a housing 24 located adjacent the inlet portion of the refrigerator and surrounding a straight track portion 40 of the conveyor belt is provided within the housing. It includes nozzle means 150 for expanding liquid carbon dioxide or liquid nitrogen over the surface of the disposed conveyor belt.

In addition to substantially complete coverage of the surface of the conveyor belt for efficient and rapid initial freezing of food products, the expansion nozzle means described above also allows the conveyor belt as well as the food carried thereon to be pre-treated to produce a food product. can rapidly harden the outer skin and reduce moisture loss from the interior of the food.

Since the foregoing objects of the invention may be easily and efficiently achieved and certain modifications may be made in the foregoing structure and various embodiments without departing from the scope of the invention, the foregoing description and accompanying drawings show that All matters are for illustrative purposes only.
It turns out that it is not limited.

[Brief explanation of the drawing]

1 is a perspective view of a closed chamber of a refrigerator showing the principle of the present invention; FIG. 2 is a top view of the belt conveyor shown in FIG. 1, which has a linear shape at the entrance of the refrigerator; FIG. 3 is a partial cross-sectional view taken along line 2A-2A of FIG. 2. FIG. 3 is a view of the conveyor shown in FIG. Top views of belts, Figures 4 through 8 are lines 4-4 to 8-8 in Figure 2.
9 is a side view of the conveyor belt shown in FIG. 2 in a straight section, and FIG. 1θ is a side view of the conveyor belt shown in FIG. 11 and 12 are cross-sectional views of the conveyor belt shown in FIG.
2-12; FIG. 13 is a cross-sectional view taken generally along line 13-13 in FIG. 3;
and FIG. 14 is a cross-sectional view taken along line 14--14 of FIG. 10... Freezer 12... Sealed room 22.
... Conveyor 24 ... Housing 26 ...
・Inlet opening 28... Drive drum 40...
Straight track part 44...Spiral track part 48...
...Exit opening 50...Roller 52...Rod 54.5B...Inner and outer edges 58, 66
... Inner and outer ends of rods 62, 64... Links 68... Bent wire member 70... Top surface 112... Slots 122, 124... Bent ends 130... Recesses in the drawings Engraving (no change in content) (4 others) Procedural amendment dated December 6, 1999, 1999 Patent Application No. 289858 2, Title of Invention Freezer 3° Relationship with the case of the person making the amendment Patent application Person Address Name: Liquilad Carbonic Corporation 4, Agent Address: Shin-Otemachi Building, 2-2-1 Otemachi, Chiyoda-ku, Tokyo 206-ku 5, Subject of amendment

Claims (1)

[Claims] 1) an insulated sealed chamber for keeping the internal temperature below atmospheric temperature; means for forming an inlet and an outlet in the sealed chamber; an endless conveyor belt for conveying products, said endless conveyor belt traveling first along a straight track section and then along a spiral track section constituting an important part of the overall track of said belt; and cooling means for establishing a temperature in the enclosed chamber sufficiently low to satisfactorily remove heat from products being conveyed along the conveyor. Refrigerator, characterized in that it is constructed such that appropriate portions of the belt only widen in the longitudinal direction when changing its direction during the transition from the straight track section to the helical track section. 2) The refrigerator of claim 1, wherein the belt includes a plurality of transverse rods extending from a laterally inner edge to an outer edge thereof, the rods being adjacent to the laterally inner edge of the helical track portion. The links and rods along the outer edge of said belt are interconnected by first links near the ends of said belts, but are substantially unprovisioned for longitudinal movement in the relative spreading direction; The interconnection between the A refrigerator characterized in that the refrigerator is adapted to allow longitudinal movement in a spreading direction. 3) The refrigerator of claim 2, wherein the conveyor belt includes a fabric consisting of a plurality of folded wire members, each of the wire members being wrapped around a pair of transverse rods to support the food product. A refrigerator characterized by forming a widened upper surface for storage. 4) The refrigerator according to claim 3, wherein each of the wire members is located in a generally parallel horizontal plane,
and having a plurality of alternating upper and lower members interconnected by curved members bent around the transverse rod, the refrigerator being generally formed in a zigzag configuration. . 5) A refrigerator as claimed in claim 4, wherein the second link has a longitudinal slot and interconnects adjacent rods along the lateral outer end of the belt, the slot being at the end thereof. receiving said transverse rod near said section and being of sufficient length to permit desired relative movement of said rod in changing from said straight trajectory configuration to said curved configuration of said helical trajectory. refrigerator. 6) In the refrigerator according to claim 5, the lower member of each of the wire members has an upwardly bent portion formed at a central position, and the bent portion changes between a linear form and a curved form of the belt. A refrigerator having generally uniformly sized leading and trailing edge pockets that limit the amount of relative movement of said lateral rods during refrigerating. 7) A refrigerator according to any one of claims 1 to 3, characterized in that the cooling means maintains a temperature of approximately 0° C. or lower so that food therein is frozen. 8) The refrigerator according to any one of claims 1 to 3, wherein the cooling means includes means for injecting liquid carbon dioxide or liquid nitrogen to the product carried on the belt. Machine. 9) A refrigerator according to any one of claims 1 to 3, wherein the sealing means includes an inlet portion through which the linear track portion of the belt extends, and wherein the inlet portion is provided with a liquid refrigerant. A refrigerator characterized by being provided with an injection means for injecting water. 10) A refrigerator according to any one of claims 2 to 4, wherein the belt drive means includes rotatable drum means mounted for rotation about a vertical axis, the outer surface of the drum being Refrigerator characterized in that one link engages with the lateral inner edge region of the belt in which it is located. 11) an insulated closed chamber for maintaining the temperature therein below ambient temperature; means for forming an inlet and an outlet in the closed chamber; and a conveyor for conveying food through the closed chamber from the inlet to the outlet; Belt means comprising a plurality of interconnected belt sections movable longitudinally relative to each other to change the belt from one configuration to another, and comprising a linear track section and an entire conveyor belt. said conveyor belt means extending along a helical track section that occupies a significant portion of the length of the track; and an endless drive belt that travels first along a straight track section and then along a portion of the helical track section. a conveyor belt drive means for driving said conveyor belt, comprising: a cooling means for establishing a temperature in said closed chamber sufficiently low to satisfactorily remove heat from food conveyed along said conveyor; Refrigerator characterized in that the belt means is constructed such that when changing its shape during the transition from said straight track section to said spiral track section, a suitable area of said belt expands only in the longitudinal direction. 12) A refrigerator according to claim 11, wherein the conveyor belt means includes first and second links adjacent to the inner and outer lateral edges, respectively, and the inner and outer lateral edges. a plurality of rods, the inner ends of the rods interconnected to adjacent first links, and the outer ends of the rods interconnected to adjacent outer links, thereby providing a connection between the inner ends of the rods. There is virtually no provision for relative longitudinal movement, while relative longitudinal movement between the outer ends of said rods is such that the conveyor belt means changes from its straight track form to the desired curvature relative to said helical track. Refrigerator characterized in that it is allowed an amount sufficient to allow for the increase in distance that occurs during the transition to a curved configuration having a radius.