US3495575A

US3495575A - Heaters for liquids

Info

Publication number: US3495575A
Application number: US742921A
Authority: US
Inventors: Henry Mansfield
Original assignee: Individual
Current assignee: Individual
Priority date: 1967-07-07
Filing date: 1968-07-05
Publication date: 1970-02-17
Anticipated expiration: 1987-02-17
Also published as: DE6751712U; GB1177409A; FR1590643A

Description

H MANSFIELD HEATERS FOR LIQUIDS 3 Sheets-Sheet 1 Filed July 5, 1968 INVENTOR HENRY MANSFIELD 7 BY W444 ATTORNEY Feb. 17, 19 70 MANSFIELD nm'rnns FOR LIQUIDS 3 Sheets-Sheet. 2

Filed my 5, 195a mm. Eu MM E INVENTOR HENRY MANSFIELD BY W I A ORNEY H. MANSFIELD HEATERS FUR LIQUIDS Feb. 17,1970

. 3 Sheets-Sheet 3 Filed July 5. 1968 mvmron HENRY MANSFIELD w 2' v I I W TTORNEY United States Patent 3,495,575 HEATERS FOR LIQUIDS Henry Mansfield, Greenhurst, St. Lurkers Road, Dosely, Dawley, Shropshire, England Filed July 5, 1968, Ser. No. 742,921 Claims priority, application Great Britain, July 7, 1967, 31,320/ 67 Int. Cl. F22b 7/12 US. Cl. 122-149 3 Claims ABSTRACT OF THE DISCLOSURE The liquid heater is particularly suitable as a water heater for installations such as laundries and comprises a cylindrical glass fibre tank having at least one stainless steel end plate at one end for the location of immersion tubes, ducts and heating and control means.

The present invention concerns improvements in or relating to liquid heaters and specifically to water heaters for use in la-undries and laundrettes.

For washing purposes in lanndries and laundrettes it is essential to have a ready supply of clean, hot water. Normally this is achieved by the provision of a heater and a storage tank which prove cumbersome, space consuming and ineflicient.

According to the present invention a liquid heater comprises a substantially cylindrical, closed glass fibre tank for containing liquid and having a stainless steel end plate secured at at least one end for the location of immersion tubes, ducts and heating and control means.

The heating means may be one or more immersion tubes extending into the tank for example for receiving combustion products from an oil or gas fired burner, in which case the tube or tubes terminate in a flue located on the end plate and tubes may be interconnected with an exhaust duct. Safety devices such as pilot lights, flame failure controls and low pressure cut-outs and pressure governors may be provided and the operation of the burners be controlled by a thermostat. Alternatively the heating means may be electricity or waste heat. A liquid pressure safety valve may also be incorporated.

One or each of the ends of the tank may be provided with stainless steel end plates secured to a flange found at the end of the cylindrical portion of the tank, for example by bolts engaging through an annular ring which overlies the stainless steel end plate in the region of the flange and through the flange to a further annular ring where-upon they are engageably locatable by means of nuts.

In the case when the apparatus of the present invention is to be used as a water heater, ducts in the form of mains inlet and ring pipes will be connected to the end plate and the mains water pressurised by a suitable cold water pump. A water pressure safety valve may be provided in the outlet ring pipe. If the heated water is to be circulated externally of the heater a pump may be provided in the ring pipe and the inlet of the ring pipe to be located iii the end plate.

In a preferred embodiment of the invention the cylindrical tank is made of laminated Glass Reinforced Plastics e.g. Fibreglass cloth having one convex end and an outwardly directed flange at the other end of the same material. A stainless steel end plate is secured by means of bolts to the flange in sealing engagement therewith and plate may be supported inside the tank and there should be a clearance between the tubes and the tank walls to avoid subjection of the latter to excessive temperatures crisscross reinforcing ribs may be provided on the end plate and a circular flange be provided at right angles to the end plate for supporting the cylinder end and flange.

A pipe is secured to the end plate for the inlet of cold water pressuried by a cold water pump. A pressure of 32 pound per square inch is required and British Standard Tests would call for a pressure of 48 pounds per square inch. It has been found that pressures up to 58 pounds per square inch may be used without failure with a water running temperature of F. A thermometer gauge is also located on the end plate.

A gas burner is secured to each of the lower limbs of each of the four immersion tubes to give an input of approximately 450,000 B.t.us and are controlled by two thermostats, a pressure governor and flame failure and low pressure cut-outs. Two thermostats are used for reasons of safety. The exhaust ends of the immersion tubes are connected to the end plate and communicate with a flue located on the end plate which is in turn connected to an exhaust duct or chimney which may be provided with suitable means for preventing downdraughts. It has been found that the maximum temperature for the heater should be about F. An outlet ring pipe is located in the upper region of the end plate having a pressure safety valve set at 40 pounds per square inch. A pump is located in the ring pipe for circulation of the water and the ring pipe inlet is located also on the end plate.

At least one pilot light may be provided for each burner. Should one pilot light fail, the supply to the pilot is cut-off and the unit can then operate at 75% load, which is an important feature where unattended heaters are operating 24 hours per day. An additional liquid container may be provided on top of the heater if additional storage of hot-water is required and a thermal insulation jacket made of polyurethane may also be provided.

The present invention will be described further, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view from one end of a heater showing a portion of the heater cylinder;

FIG. 2 is a longitudinal cross-section of the heater without the burners and other controls;

FIG. 3 is a section on the line IIIIII of FIG. 2 showing a reinforcing flange and criss-cross stiifeners; and

FIG. 4 is a detail of the heater showing support struts and immersion t-ubes viewed in direction of arrow IV of FIG. 2.

The heater comprises a glass reinforced plastics material cylinder 12, one end of which is convex and the other end open but having a stainless steel end plate 13 securable thereto. Legs (not shown) are provided to support the cylinder and end plate on any supporting surface upon which the heater may be positioned.

Four helically wound U-shaped immersion tubes 14 are locatable within the cylinder 12 and provided with a clearance of at least two inches from the lower walls of the cylinder with the aid of support struts 15 which rest on cushioned seat 15 which may be of a heat resistant plastics material. The U-shaped tubes 14 extend into the cylinder 12 and the ends of each pair are separately connected to two flanged apertures 16/16, 17/17, 18/ 18' and 19/19 by means of a continuous weld (Argon Arc process).

The lower of each pair of apertures i.e. 16, 17, 18 and 19, connected to the lower limbs of the U-shaped tubes 14, are adapted to receive burners 20 provided with known control and safety devices as already mentioned. The burners 20 are fed from mains supply 21. The upper 3 of each pair of apertures, i.e. 16, 17, 18' and 19', communicate with a flue 22 secured to the end plate 13 and having an exhaust duct or chimney 23. A cold water inlet 24 is provided in the lower region of the end plate and a cold water pump (not shown) may be provided for pressurisation. An outlet ring pipe 25 having a pressure safety valve (not shown) is provided in the upper region of end plate 13 and a pump (not shown) may be provided in the ring pipe for circulation of the water if desired. A ring pipe inlet 26 is also located on the end pipe and may be suitably insulated. A thermometer 27 is also found on the end plate and two thermostats 28 and 28' are provided, for reasons of safety, which control the burners 20.

The open end of the glass fibre cylinder 12 has an outwardly directed flange 29 formed thereat and bolt receiving apertures 30 radially spaced therein. Corresponding bolt-receiving apertures 31 are found in the periphery of the end plate and two

mild steel rings

32 and 33, also with corresponding bolt receiving apertures, are positionable, one 32 overlying the end plate 13 and the other, 33, overlying the cylinder flange 29. High tensile bolts 34 hold the end plate 13 and rings 32 and 33 securely against the flange 29.

A circular stainless steel reinforcing flange 35, extending into the cylinder 12, is connected at right angles to the end plate and reinforces the cylinder flange and the region thereof. Criss-cross stiflFners 36 are secured to the end plate 13 as additional reinforcement.

I claim:

1. A liquid heater comprising a .glass fibre cylinder having a closed convex end and an open end and a stainless steel end plate securable to said open end, said end plate having at least one liquid inlet in its lower region and a hot liquid outlet in its upper region and at least one U-shaped immersion tube adapted to extend into said cylinder and connected to a combustion product inlet and outlet found substantially one below the other respectively in said end plate, said inlet adapted to receive a burner and said outlet communicating with a flue and exhaust duct, said end plate being securable to said cylinder by means of bolts engaging through a ring overlying said end plate, through said end plate, through an outwardly directed flange formed on said open end and through a further ring overlying said outwardly directed flange.

2. A liquid heater according to claim 1 wherein crisscross reinforcing ribs are provided on the inward facing side of said end plate and a circular reinforcing flange located in the region of said flange and abutting against the inner surface of said cylinder is provided on said end plate.

3. A liquid heater according to claim 1 wherein said burner is provided with safety devices and at least one thermostat is located on said end plate together with a temperature gauge; said hot liquid outlet communicating with a ring pipe having a circulation pump therein with residual liquid being returned via said end plate into said cylinder, said hot liquid outlet having a pressure safety device.

References Cited UNITED STATES PATENTS 2,354,932 8/1944 Walker et al 122149 XR 2,582,134 1/1952 Kimmell et a1. l22l49 XR 1,939,944 12/1933 Barthel et al 122-149 KENNETH W. SPRAGUE, Primary Examiner