US3797267A

US3797267A - Ice rake control

Info

Publication number: US3797267A
Application number: US00306712A
Authority: US
Inventors: W Hagen
Original assignee: Turbo Refrigerating Co
Current assignee: Turbo Refrigerating Co
Priority date: 1972-11-15
Filing date: 1972-11-15
Publication date: 1974-03-19
Anticipated expiration: 1991-03-19
Also published as: NO137519C; JPS4981945A; NO137519B; CA980713A; GB1434823A; JPS5039855B2

Abstract

A control system for an ice rake in ice making apparatus comprising means to activate the ice rake to raise the ice rake at predetermined intervals for a predetermined period of time when ice is supplied to the ice making apparatus and means to simultaneously energize the ice rake to drive the flites of the ice rake in a forward direction for a predetermined time and to drive the flites in a rearward direction for another predetermined time.

Description

United States Patent 1 191 Hagen [111. I 3,797,267 [451 Mar. 19, 1974 [5 ICE RAKE CONTROL 3.587.241 6/1971 Hagen 62/63 3,190,083 6/1965 Miller 62/349 [75] Invenwr' Hagen, Argyle 3.074.252 1/1963 Tippmann et al.. 62/347 [73] Assignee: Turbo Refrigerating Com 3.246.481 4/1966 Douglas et al. 62/320 Demon, Tex.

. I Primary Examiner-William E. Wayner [22] 1972 Assistant ExaminerWilliam E. Tapolcai, Jr. [21] Appl. No.: 306,712

Related US. Application Data 57 ABSTRACT [63] g-g of July A control system for an ice rake in ice making apparatus comprising means to activate the ice rake to raise [52] U S Cl 62/233 62/344 the ice rake at predetermined intervals for a predeter- [51] i 5/18 mined period of time when iceis supplied to the ice [58] /233 344 making apparatus and meansto simultaneously energize the ice rake to drive the flites of the ice rake in a [56] References Cited forward direction for a predetermined time and to drive the flites in a rearward direction for another pre- UNITED STATES PATENTS 1 1 determined time. 2.222.024. 11/1940 Field 62/344 2.791.103 5/1957 Guild 62/344 11 Claims, 5 Drawing Figures 0 no 1 ul 0 i I: I l

| 15 I I4. 1 I. ak yFgi-I'; 1 ksf iaa k -k l v i' 'l 'e' van PATENTED MAR 19 I974 SHEET 3 [1F 4 ICE RAKE CONTROL This is a continuation-in-part of my copending application Ser. No. 273,327, filed July 19, 1972.

This invention relates to the manufacture of ice in bulk, and more particularly to apparatus for the manufacture, storage, and dispension of large quantities of ice.

A variety of apparatus for use in the manufacture of large quantities of ice are now known to those skilled in the art. Representative ice-making machines are described in U.S. Pat. Nos. 3,074,252, 3,190,083, 3,246,481, 3,546,896, 3,587,241, and others. Commercial installations forthe manufacture of ice, and particularly fragmented ice, generally include icemaking machines which actually form the ice and which are elevated above a bin, such as on a second floor of the installation. The ice makers discharge fragmented ice into a conveyor which in turn discharges the ice through an opening into the bin.

However, the automatic and sanitary handling of bulk, fragmentary ice once it is discharged into such a bin presents exceedingly difficult and specialized problems. Fragmented ice, when stored in a bin, can change characteristics during storage. For example, flakes of thin ice tend to break into smaller pieces akin to snow. Under certain temperature conditions, pieces of ice can fuse together. In addition, portions of ice in the lower part of a pile tend to fuse under the weight of a pile.

As a result of the foregoing special problems, fragmented ice in bulk cannot be regarded as being made up of discrete particles and is not even a product having definite handling properties. Fragmentary ice in bulk has no definite angle or repose. Consequently, fragmentary ice in bulk form is virtually incapable of flowing out of a large bin by gravity. t j

The inability of fragmented ice in bulk to flow with gravity has been previously recognized, and the art has sought to employ'a device known as an ice rake for many years to facilitate the handling of ice. An ice rake is a type of a drag conveyor which contacts the top of a pile of the ice and is maintained in contact therewith by a system of cables by which the rake is suspended. The ice rake has been found to be the only mechanism for use in the handling and storage of bulk fragmentary ice. However, such ice rakes are subjected to extremely high stresses during use, with the result that breakage of the ice rake is a common occurrence. It is not uncommon for an ice rake to sustain breakage within ninety days of use.

Such ice rakes of the prior art are formed of a plurality of channel members which are displaced about a structural member, such as on a chain or the like. The channel members each have teeth fixed thereto, and the teeth on each of the channel members are in alignment. As the structural member is maintained just above the level of the ice in the bin, the structural members are advanced in either a forward or rearward direction in the bin to uniformly distribute the fragmented ice over the length of the bin. However, if the bin is being filled at a rate even slightly greater than the rate at which the rake is being raised, the rake tends to be buried in the ice. As the channel members having the teeth fixed thereto are displaced within the bin, the teeth tend to be broken off by ice which has become fused. Even where the teeth are not broken off, the

aligned teeth tend to simply form continuous grooves in the surface layer of the ice in the bin, and the subsequently lowering of the entire ice-rake mechanism brings the channel members into contact with the top layer of ice, and results in breakage of the channel members or the mechanism by which such channel members are mounted.

In my copending application Ser. No. 273,327, filed July 19, 1972, there is disclosed and claimed an improved ice rake in which the teeth of the ice rake are It is accordingly an object of the present invention to provide an ice rake and control means therefor to facilitate the uniform distribution of ice in a storage bin during loading and unloading of the bin.

It is a related object of the invention to provide an ice rake and control means therefor in which the move ment of the ice rake is programed to avoid overstressing of the rake and in which the optimum distribution of raking directions and raking times is achieved for any variation in the rate of loading and/or the point of loading of ice into the bin.

These and other objects and advantages of the invention will appear more fully hereinafter, and, for purposes of illustration, but not of limitation, an embodiment of the invention is shown in the accompanying drawing in which:

FIG. 1 is a side view in elevation of preferred icemaking apparatus for use with this invention;

FIG. 2 is an end view in elevation of the apparatus shown in FIG. 1;

FIG. 3 is a view illustrating the staggered relationship of the teeth in the flites of the ice :rake preferably employed with this invention;

FIG. 4 is a sectional view taken along the lines 4-4 in FIG. 3; and

FIG. 5 is a schematic view of the control system employed with the ice rake mechanism.

The concepts of the present invention reside in a control system for apparatus for use in the manufacture, storage, and/or dispensation of ice which includes means for generating fragmented ice in bulk and a bin positioned to receive the fragmentary ice from the generating means. In accordance with the preferred practice of the invention, the bin is provided with an ice rake including a frame and a plurality of flites carried on the frame and movable along the frame. Each of the flites of the ice rake is in the form of a channel member, preferably having a U-shaped cross section.

The invention will be described by reference to the ice rake control system of this invention as used in the operation and control of the ice rake system described in the earlier copending application referred to above. However, the ice rake control system can also be employed in the operation and control of ice rake systems known to the prior art. It has been found that the control system of the invention provides optimum distribution of raking directions and times for any variation in the rate of ice production and point of entry of ice into the bin to thereby prevent the ice rake from being subjected to excess stresses.

Referring now to the drawings for a more detailed description of the invention, there is shown in FIGS. 1 and 2 ice-making apparatus for operation with the control system of the invention The apparatus includes a storage bin or compartment 10 having suitably insulated walls 11 and floor 13 which is supplied with bulk fragmentary ice by ice generating r forming means 12 which can advantageously be one of the ice-making machines of the type described in the foregoing US. patents. The bulk fragmentary ice is discharged as it is formed into a conveyor such as a screw conveyor 14 provided with auger 16 to convey the ice to a discharge chute or aperture 18 communicating with the bin.

As will be appreciated by those skilled in the art, the apparatus contemplates one or several ice-forming units 12 to supply bulk fragmentary ice to the bin 10, depending somewhat on the size of the bin. For example, the ice-forming units can be positioned side by side as illustrated by

units

12 and 12 in FIG. 2 and/or units can be distributed longitudinally along the bin 10.

Bulk, fragmentary ice can be discharged into the bin at any point in the bin since the ice rake serves to distribute the ice over the length of the bin as more fully described hereinafter. Thus, the discharge opening 18 of the conveyor can be positioned near the forward end of the bin as illustrated in FIG. 1 of the drawing, or, if desired, it can be positioned at any other point along the longitudinal axis of the bin.

The ice contained in the bin can be discharged from the bin in a variety of ways. In the preferred embodiment illustrated in FIG. 1 of the drawing, the floor 13 of the bin is provided with a transversely extending conveyor 20 such as a screw conveyor which is positioned in a recess 22 formed in the floor 13 toward the forward end of the bin.

The bin is also provided with a door 24 which is mounted on a plurality of support arms 26 which are pivotally fixed to the forward wall 1 1 at 28. In this way, the door can be displaced upwardly away from the floor 13 and toward the wall 11 to which it is fixed as shown by the broken lines in FIG. 1. In the closed position shown in solid lines of FIG. 1, the door is positioned between the interior of bin 10 and the recess 22 to prevent ice in the bin from falling into the recess 22. As the door 24 is raised upwardly and toward the wall 11 of the bin, the door is advanced toward the wall 11 to expose the recess 22 to the bulk, fragmentary ice contained in the bin 10 to permit the ice to engage the conveyor 20 in recess 22 for removal of ice from the bin 10.

To prevent ice from falling behind the door 24, that is, between the door 24 and the wall 11, the floor 13 is preferably provided with a vertical wall member 30 which is positioned between the conveyor recess 22 and the forward wall 11 at a height sufficient to form a barrier, with the door 24, to prevent ice from becoming lodged behind the door.

The ice-rake mechanism is shown in FIGS. 1 to 4 of the drawings. As is perhaps best illustrated in FIGS. 1 and 2 of the drawing, the ice rake includes a structural member or frame generally designated at 32. Each end of the frame 32 is provided with a pair of laterally spaced pulleys or sprockets 34. The pulleys or sprockwhich extend across substantially the entire width of the bin 10 (see FIG. 2) and which are spaced each from the other along the endless chains 36 longitudinally in the bin.

Each flite 38 of the rake includes a channel member formed of a base 40 and a pair of spaced

flange elements

42 and 44, as seen in FIG. 4. Thus, the channel members have a generally U-shaped cross section, and extend substantially over the width of the bin 10. As is also shown in FIG. 4, the base 40 of the channel member is fixed to the chains 36 in any convenient manner such that the flange elements extend away from the chains 36 and away from frame 32.

At least one of the pulleys 34 is adapted to be driven by a motor or the like 46, as can be seen in FIG. 2 of the drawing. It is generally preferred that the motor 46 be capable of driving the endless chains 36 having the rake flites fixed thereon in both directions. Thus, the flites 38 shown below the frame 32 in FIG. 1 of the drawing are capable of being advanced in a forward direction, that is, toward the bin door 24 as well as in the rearward direction, that is, away from the bin door 24.

As indicated above, one of the preferred features of the present invention resides in the use of

rake teeth

48 and 50, as shown in FIG. 4 of the drawing, which are fixed to the

flange members

44 and 42, respectively, of the rake flites. The

teeth

48 and 50 as described above preferably take the form as narrow projections which can, for example, simply be welded to the channel members, as shown in FIG. 4 of the drawing. In order to prevent overstressing of the

teeth

48 and 50, the teeth are generally of a fairly narrow width, for example, of the order of l to 3 inches, although wider or narrower teeth can be used as desired.

It is preferred that the teeth on adjacent flites be staggered relative to each other. One suitable arrangement of such staggered teeth is shown in FIG. 3 of the drawing, which illustrates the use of four flites. For the sake .of clarity, these four flites are illustrated in a side-byside arrangement to demonstrate the staggered-teeth arrangement. As is shown in FIG. 3, flite No. l, which is generally designated as 52 in the drawing, includes

teeth

48 and 50 fixed to alternating

flange elements

44 and 42, respectively. The adjacent flite, or flite No. 2, which is generally designated as 54, includes a plurality of

teeth

48 and 50 which are out of longitudinal alignment with the corresponding

teeth

48 and 50 of the first flite 52. In other words, the

teeth

48 and 50 of flite 52 are staggered relative to

teeth

48 and 50 of flight Similarly, the third flite, which is generally designated and 56, includes teeth 48" and 50" which correspond to

teeth

48 and 50 of flite 52. Teeth 48" and 50' of flite 56 similarly correspond to

teeth

48 and 50 of flite 54, except that

teeth

48 and 50 are staggered relative to teeth 48' and 50' of the adjacent flite 54.

The fourth flite, which is generally referred to as 58 in FIG. 3 of the drawing, includes teeth 48" and 50" which correspond to the teeth of

flites

52, 54, and 56. It is generally preferred that the teeth 48" and 50" of flites 58 be staggered relative to the teeth of at least one of the adjacent flites 56 and 52.

Thus, as the

flites

52, 54, 56, and 58, fixed to the endless chains 36, are advanced in either the forward or rearward directions in the bin 10, the

teeth

48 and 50 on each flite penetrate into the ice to cut tracks or grooves in the surface of the ice layer contained in the bin 10. Since the teeth of adjacent flites are staggered relative to each other, the teeth of successive flites do not simply track in the grooves formed by the teeth of the preceding flites, but, on the contrary, cut new grooves in the surface of the ice adjacent to those grooves cut by the teeth of the preceding flites to thereby form closely spaced ridges in the surface of the ice layer. These relatively narrow ridges can easily be broken away as the

flange members

44 and 42 of each flite contact the surface of the ice.

As will be appreciated by those skilled in the art, the staggering of the teeth of each flite serves to decrease the width of the ridges formed in the surface of the ice without increasing the number of teeth employed on the flites and consequently without increasing significantly the power required to drive the flites through the ice. Since the ridges formed in the surface of the ice are more closely spaced, they are characterized by less strength and are susceptible to being broken away and carried along by the flange elements of the rake as the odic running of the hoist motor 66 in the up direction. The raising of the ice rake can be accomplished by energizing one side of a reversing starter 76 which is shown in the drawing as HU. The upward movement of the ice rake within the bin is controlled by the up-timer 78 which includes two timer modules, a frequency module which can be adjusted, for example, from Q to minutes, and a duration module which can be adjusted, for example, to O to 3 minutes. The setting of the frequency module will periodically energize the duration module.

For example, if the frequency module is set to 4 minutes and the duration module is set to 18 seconds, the frequency module will close the switch 80 to energize the hoist motor starter 76 for a period of 18 seconds. Thus, every 4 minutes the rake mechanism will be raised for an 18 second period. When the frequency module of switch 80 energizes, a latch relay 82 designated as STR in the drawing is momentarily energized to close the contacts of latch relay 84 to permit flow of current from wire 86 to wire 88 and thereby energize the timer module 90. Relay 84 is a latch relay and consequently remains closed once energized until mechanchannel members or flites of the rake are advanced in a one direction or another in the bin.

within the bin so that the flange members on each flite of the rake on the under side of the frame 32 can be maintained just above the surface of the ice contained in the bin 10, the frame 32 of the ice rake can be suspended from the ceiling 61 of the bin by means of a pair of cables or the like, 60 and 62, the endsof which are fixed to the rake and pass over pulleys 64 to a suitable motor-driven winch 66 or the like. By activating the winch 66, the frame 32 and consequently the

flange elements

44 and 42 of each flite of the rake can be maintained at the desired level within the bin. As shown in FIG. 1, it is sometimes desirable to provide the longitudinal walls of the bin 10 with guide means 15 to prevent any forward or rearward movement of the rake while in use.

The control system for the ice rake assembly of this invention is schematically illustrated in detail in FIG. 5 of the drawing. The control mechanism is powered by a power supply 60 which is operatively connected through a circuit breaker 62 to a master switch 64 and an indicator light 66 designated as P 6 in the drawing. The indicator light, for example, can be a green light which, when illuminated, indicates that the power is on. Also included in the circuit is a switch 68 which permits the ice rake to be displaced manually upwardly, shut off manually downwardly and placed in the automatic position. The master switch 68 is preferably provided with an indicator light 70 which is designated as P 7 in the drawing to indicate that the ice rake is being raised manually when illuminated. Similarly, the switch 68 is provided with an

indicator light

70, 72 which is shown in the drawing as P 8 to indicate that the ice rake is being lowered manually. The automatic position of the switch 68 is preferably provided with an indicator light 74 which is designated as P 1 in the drawing to indicate that the control system is switched in the automatic position.

When the ice is being loaded into the bin as described above, the rake assembly is raised in the bin by the periically opened. The up-timer 78 which includes the timing motor 92-preferably drives a shaft with a mechanical protrusion or pawl (not illustrated in the drawing for purposes of simplicity) and after one complete fevolution, the pawl mechanically disengages the contacts of the latch relay 84 to consequently stop the timer motor 92. Thus, every time the frequency motor 92 of the up-timer 78 closes, the reversing timer receives a single impulse and the timing motor 92 runs through one revolution. In each instance, the starting and finishing position of the tirning motor 92 is the same.

As shown in FIG. 6 of the drawing, the output of the timer motor 92 is connected to two cams each of which can be adjusted so that an arc of its circumference has a smaller radius than the radius of the remaining circumference. A microswitch bearing on the circumference of the cam can thus be activated when the cam rotates through the aforementioned arc to contact the microswitch. The two microswitches are illustrated in the drawing as 94 and 96, respectively. When the first microswitch 94 is closed, the rake is caused to be displaced about the frame in the reverse direction since microswitch 94, when energized, energizes the coil of a reversing starter 98. When the second microswitch 96 is energized, the rake is caused to run in a forward direction by energizing the other coil of the reversing starter 100. By adjusting the two cams on the starter motor 92, the rake can be caused to run in reverse for a given period of time, come to rest and then run forward for the same or a different period of time to coordinate the running of the rake with the time during which it is being raised.

Thus, every time the reversing starter is energized to raise the rake for a predetermined period of time, the up-timer 78 is likewise activated to cause the rake to be driven in the forward and reverse directions for the same or different times as predetermined by cams on the timer motor 92. Consequently, the drive of the rake can be coordinated with the raising of the rake mechanism to provide optimum ice distribution in the bin regardless of the rate of ice production or the point of entry of ice into the bin and thereby substantially prevent overstressing of the rake flites and teeth.

The control system also preferably includes a pair of down-timers 100 and 102 as shown in FIG. of the drawing, with the former being adapted to lower the ice rake mechanism by energizing the down reversing starter 104 with no ice production and the latter to lower the ice rake mechanism by energizing the reversing starter 104 when there is ice production.

In the operation of the apparatus of this invention the rake is raised at a rate corresponding to the rate at which ice is fed to the bin from the discharge opening 18 during filling of the bin. As the bin is being filled with ice from the ice-making machine 12, the rake is activated by the control system of the invention as described above to uniformly distribute the bulk fragmentary ice through the bin.

When it is desired to discharge ice from the bin by way of the conveyor 20, the door 24 is opened or raised to the position shown in broken lines in FIG. 1 whereby the ice is capable of contacting the conveyor screw 20 in the recess 22. When unloading the bin, the rake flites on the under side of the frame 32 are continuously advanced in the forward direction to continuously advance ice in the bin from the rearward end of the bin toward the front whereby the ice is discharged by way of the conveyor 20. As the ice is being discharged from the bin, the rake is lowered by way of

cables

60 and 62 to permit the flites of the rake to scrape the ice from the top of the bin and cause it to fall into the conveyor 20 in the recess 22 of the floor.

In view of the foregoing, it will be apparent that I have provided a new and improved control system for use in the manufacture, storage, and dispensation of fragmentary ice in bulk which facilitates the handling of ice both in the loading and unloading of storage bins. The ice rake control system of this invention represents a significant improvement in the art, since the ice rake embodying the feature of this invention is subjected to significantly reduce stresses in use and consequently enjoys a drastically longer useful life.

It will be likewise apparent that various changes and modifications can be made in the details of construction, procedure, and use without departing from the spirit of the invention, especially as defined in the following claims.

I claim:

1. An ice-making apparatus comprising means to form bulk fragmentary ice, a storage bin positioned to receive ice from the means to form ice, means to remove ice from the bin, an ice rake mechanism positioned in the bin and adapted to be raised and lowered in the bin, said ice rake mechanism including rake flites adapted to be driven in a forward direction and a rearward direction in the bin to distribute ice in the bin, means to raise and lower the ice rake mechanism and means to drive the flites in the forward and rearward direction in the bin, the improvement of a control system for the ice rake mechanism comprising starter means to activate the means to raise the ice mechanism at predetermined intervals for a predetermined period of time when ice is being supplied to the bin and means to simultaneously energize the means to drive the flites to drive the flites in a forward direction for a predetermined time and to drive the flites in a rearward direction for another predetermined time.

2. Apparatus as defined in claim I wherein the means to energize the means to drive the flites are activated by the starter means.

3. Apparatus as defined in claim 1 wherein the starting means includes a reversing starter to activate the means to raise the ice rake mechanism, and timing means including frequency timer means to control the invervals at which the time to raise the ice rake mechanism are activated and duration timer means to control the period during which the means to raise the ice rake mechanism are activated to raise the ice rake mechanism.

4. Apparatus as defined in claim 3 which includes switching means activated by the timing. means, said switching means being adapted to activate the means to drive the flites to drive the flites in a forward direction for a predetermined period of time and to drive the flites in a rearward direction for another predetermined period of time.

5. Apparatus as defined in claim 1 wherein the flites include channel members extending transversely to the frame across the bin,'each of the channel members including at least one flange member extending downwardly from the frame member to engage the ice to displace the ice in the bin and a plurality of teeth fixed to the flange member adapted to penetrate the ice in the bin, with the teeth fixed to flange members of adjacent flites being staggered relative to each other whereby the teeth on adjacent flites penetrate the ice at closely spaced intervals to leave narrow ridges in the ice which can be fractured by contact with the flange members of each flite as the flites are advanced in the bin by the drive means.

6. Apparatus as defined in claim 5 wherein each channel member includes a pair of spaced, parallel flange members.

7. Apparatus as defined in claim 6 wherein both of the flange members of each flite have teeth fixed thereto, with the teeth of each flange member of each flite being staggered relative to each flange member.

8. Apparatus as defined in claim 5 wherein the ice rake is suspended in the bin at a level slightly above the level of the ice in the bin.

9. Apparatus as defined in claim 5 wherein the means to remove the ice from the bin includes conveyor means located adjacent to one end of the frame member.

10. Apparatus as defined in claim 9 wherein the floor of the bin includes a recess therein, and the conveyor means is positioned in the recess.

11. Apparatus as defined in claim 9 wherein the means to remove ice from the bin also includes a door panel, said door panel being mounted adjacent to the conveyor means on a plurality of pivoted arms whereby the door is adapted to be raised upwardly and away from the conveyor means to permit ice in the bin to engage the conveyor means for removal from the bin.

UNITED STATES PATENT OFFICE I V CERTIFICATE OF CORRECTION Patent No, 3,797,267 Dated March 19, 1974 Inventofls) William F. Hagen It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

. Column 1, line 35, change "or" to of fittest: MCCOY M. GIBSONQ'JR.

Column 8, linell, change "'time" to m eans Signed and sealed this 16th day of July 197R.

SEAL) C; MARSHALL DANN Attesting Officer Commissioner of Patents

Claims

2. Apparatus as defined in claim 1 wherein the means to energize the means to drive the flites are activated by the starter means.

4. Apparatus as defined in claim 3 which includes switching means activated by the timing means, said switching means being adapted to activate the means to drive the flites to drive the flites in a forward direction for a predetermined period of time and to drive the flites in a rearward direction for another predetermined period of time.

5. Apparatus as defined in claim 1 wherein the flites include channel members extending transversely to the frame across the bin, each of the channel members including at least one flange member extending downwardly from the frame member to engage the ice to displace the ice in the bin and a plurality of teeth fixed to the flange member adapted to penetrate the ice in the bin, with the teeth fixed to flange members of adjacent flites being staggered relative to each other whereby the teeth on adjacent flites penetrate the ice at closely spaced intervals to leave narrow ridges in the ice which can be fractured by contact with the flange members of each flite as the flites are advanced in the bin by the drive means.