Abstract:
The present invention is drawn to a device for heating liquid feed for veal calves, although this device may have wider application. The present invention is a pre-heater system used to raise the temperature of liquid feed that is being pumped from cold storage to a mixing tank prior to being fed to an animal. Additionally, the present invention is arranged to independently supply heated water externally of the system.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to an automated, mechanical liquid feed pre-heating system. Bulk nutrient feed for livestock is commonly stored in a refrigerated environment for convenience of storage and to prevent spoilage. The nutrient must be heated to a predetermined temperature prior to feeding however, to allow the nutrient to reach its desired viscosity and palatability. Various pre-heating and feeding systems have been used to accomplish this result. One such device is disclosed in U.S. Pat. No. 4,803,955 granted to Gonsalves. Gonsalves discloses a complex, automated multi tank system having a combination of structural features, including solenoid actuated control valves, float switch assembly and nipple means, which are not shown in the present invention. Further, the Gonsalves reference does not include the independent heated water access system disclosed herein. 
     The pre-heating system of the present invention provides a multi-purpose system wherein feed is pre-heated, hot water is accessed, and cleaning is easily accomplished. Chilled nutrient is placed in the pre-heater wherein the nutrient is heated to the desired feeding temperature and pumped to a mixing and distributing area. 
     SUMMARY OF THE INVENTION 
     The present invention is drawn to a device for pre-heating liquid feed for veal calves, although it is to be understood that this device may have wider application. More specifically, the present invention is a pre-heater used to raise the temperature of liquid feed as it is being pumped from cold storage to a mixing tank prior to being fed to an animal. 
     The pre-heater of the present invention includes a stand-alone tank for heating water and a series of tubular fluid conduit coils. The water-heating tank is provided with a heating means. The fluid conduit coils include an inlet and an outlet for the liquid feed, a backflow conduit having an outlet for the hot water, and an inlet for the water source. Each inlet and outlet is further provided with valve shut-off means. The water tank is filled with water via an inlet on a water conduit. As the water contacts the heating element in the tank, it is heated to a predetermined temperature. The liquid feed conduit coil is immersed in the water tank, thereby taking on the temperature of the surrounding heated water. In use as a liquid nutrient pre-heater, nutrient concentrate is drawn from a cooled storage area into the feed concentrate coil in the pre-heating system. The feed concentrate moves through the warmed liquid feed conduit coil in the pre-heater. Transfer of heat occurs as the feed travels through the coil, and the liquid feed is warmed by the hot water surrounding the coils. The heated liquid feed exits the pre-heating system into a mixing tank where the feed is mixed with hot water to raise the temperature above a predetermined temperature. This predetermined temperature is dependent upon the chemical composition of the liquid feed. The liquid feed is then pumped to animal feeding devices. To ensure that all of the liquid feed has been removed from the pre-heater to the mixing tank, the liquid feed conduit coil is flushed by way of a backflow conduit section located intermediate the hot water outlet and the liquid feed conduit coil. 
     In addition to the preheating and flushing characteristics described above, the pre-heater is arranged to supply heated water externally of the system. This characteristic is of particular importance in a barn setting wherein washing and cleaning is desired. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the pre-heater of the present invention and includes a portion partially cut away and a portion in phantom. 
     FIG.  1   a  is a perspective view of an alternate embodiment of the present invention including an alternate flushing conduit. 
     FIG. 2 is a plan view of the conduits and valves of the present invention with the water tank in phantom. 
     FIG. 3 is an enlarged fragmentary view showing the wall of the hot water tank. 
    
    
     DETAILED DESCRIPTION 
     Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structure. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims. 
     Referring to FIG. 1, it can be seen that the preheater  10 , includes a tank  12 , water supply means  14 , a gas-fired water heating element  16 , a tubular liquid feed conduit  18 , and a tubular backflow conduit  20 . The liquid feed conduit  18  includes an inlet  22  controlled by an inlet valve  26   a,  inlet  22  communicating with a pump  23  further connected with a container  25  for storing chilled nutrient. The liquid feed conduit  18  is further provided with an outlet  24 , the outlet  24  and inlet  22  are each respectively provided with flow rate valves  26   a,    26   b,  and temperature sensing means  28 . As shown in FIGS. 1 and 2, the valves  26   a,    26   b  are indicated as manually operated, however it is within the province of this invention to utilize conventional programmable controller devices (not shown). The hot water tank  12  may be of the type commonly used with conventional hot water heaters, although any suitable tank having insulated walls  30  may be also used. As seen in FIG. 3, the wall  30  of the tank  12  may include an intermediate layer  32  having insulation capabilities in order to maximize the energy needed to heat the interior  34  of the tank  12 . This feature is desirable especially when the tank  12  is to be used in climates having severe temperature fluctuations as in a winter having sub-zero temperature. The intermediate layer  32  increases the overall energy efficiency of the pre-heater. The water-heating element  16  may be of any type such as the gas or electric heating units used in conventional water heating tanks. As seen in FIG. 1, the heating element  16  is shown as a conventional gas heat exchanger under the control of a thermostat  38 . The heating element  16  is further supplied with at least one flue  40  for exhaust of gases produced by the heating element  16  and to further assist in heating the water in the tank  12 . 
     Referring to FIG. 1, it can be seen that the tubular liquid feed conduit  18  is preferably coiled to increase the overall surface area of the conduit  18  in the heated water environment. The water supplied by water supply means  14  and heated within the tank  12  is maintained in a heated condition, therefore the liquid feed passing through the feed conduit  18  may be heated to that same temperature. The number of coils used may be of any number depending on the flow rate desired and the temperature differential between the cooled feed entering the pre-heater and the desired exit temperature. It is to be understood that the greater the number of coils, the greater the total distance the feed must travel to the outlet, and at a uniform flow rate, the longer the feed is heated in the pre-heater. Furthermore, the feed conduit  18  is constructed of a material having good heat transfer capabilities, such as stainless steel tubing, and is disposed within the tank  12 . 
     As best seen in FIGS. 1 and 2, the temperature of the liquid feed exiting the outlet  24  of the liquid feed conduit  18  is monitored by a temperature sensing device  28 , seen as a thermometer in FIG. 1. A similar temperature-sensing device  28  is also located at the inlet  22 . The temperature of the feed exiting at outlet  24  is regulated by way of the flow rate valve  26   a  located at the inlet  22  of the feed conduit  18  and the valve  26   b  located at the outlet  24 . If the thermometer  28  at outlet  24  senses an unacceptably low temperature, the user may decrease the flow rate of the feed through the feed conduit  18  by partially closing the flow rate valves  26   a,    26   b.  As the flow rate decrease, the feed remains in the pre-heater for a longer period of time prior to its exit at outlet  24 . As the time spent in the pre-heater increases, so does the temperature of the liquid feed, until it reaches the temperature of the ambient water surrounding the liquid feed conduit  18 . 
     After the desired amount of liquid feed has passed through the outlet  24 , the liquid feed conduit  18  is adapted to be flushed to remove remaining feed and further to clean the conduit  18  for future use. Flushing of the liquid feed conduit  18  is accomplished using the backflow conduit  20 . The backflow conduit  20  serves as a means of communication between the inlet  22  of feed conduit  18  and the heated water in the tank  12 . To this purpose, the backflow conduit  20  is supplied with a shut off valve  36 . When flushing of the feed conduit  18  is desired, the flow rate valve  26   a  located at the inlet  22  is closed and the shut off valve  36  on backflow conduit  20  is opened. The tank  12  is supplied with an excess of water from the water supply means  14  such that the excess water is forced past the open shut off valve  36  and into the backflow conduit  20 . As the water is forced through the backflow conduit  20 , it encounters the closed flow rate valve  26   a  on the inlet  22  of feed conduit  18 . As the water reaches the closed flow rate valve  26   a,  it is forced back through the liquid feed conduit  18  and out the open flow rate valve  26   b  on outlet  24 . After the fluid exiting the outlet  24  no longer contains liquid feed, the water supply means is discontinued and the shut off valve  36  is closed. The pre-heater  10  is in condition to receive chilled liquid nutrient for pre-heating when the flow rate valve  26   a  at inlet  18  is opened. 
     As shown in FIG.  1   a,  an alternate flushing conduit  50  may be provided between the outlet of feed tank  25 , adjacent feed tank valve  25   a,  and heated water exit valve  42 . This alternate flushing system works in the same manner as the system described above except that the alternate embodiment provides for flushing of the pump  23 , conduit downstream of the pump  23 , and valve  26   a.  Accordingly, this alternate arrangement provides for a more efficacious cleansing of the liquid feed pre-heater  10 . 
     The pre-heater  10  is further supplied with an independent heated water access means, seen as a valve  42 . As seen in FIG. 1, the pre-heater  10  is provided with a heated water exit valve  42 . The heated water exit valve  42  is preferably located at the distal end  44  of backflow conduit  20 . Heated water may be accessed directly from the tank  12  when the shut off valve  36  on backflow conduit  20  is in the closed position and the heated water exit valve  42  is in the open position. Heated water accessed in this way may be used for any of a variety of tasks, such as cleaning of used buckets or washing the user&#39;s hands. This feature is of particular importance when heated water is necessary for cleaning as it obviates the necessity of a separate, secondary water-heating unit. 
     The foregoing is considered as illustrative only of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.