CN101040566A

CN101040566A - Heating element, designed in particular for kettles

Info

Publication number: CN101040566A
Application number: CNA2005800348822A
Authority: CN
Inventors: 洛朗·盖冈
Original assignee: SEB SA
Current assignee: SEB SA
Priority date: 2004-10-13
Filing date: 2005-10-12
Publication date: 2007-09-19
Also published as: WO2006040476A1; FR2876535B1; FR2876535A1; EP1803326A1

Abstract

The invention concerns a heating element for an electrical appliance, comprising a hollow metal sheath made of good thermally conductive material, such as aluminium or copper, wherein is housed a resistive wire surrounded with insulation, said wire being capable of being supplied with electric current. The invention is characterized in that the metal sheath has an extension (10) extending in a plane and constituting a heat diffusion plate.

Description

A kind of heater block that is specially adapted to kettle teapot

Technical field

The present invention relates to have the technical field of the heater block of pipe box, wherein be placed in the metal tube by the resistance wire that centers on such as magnesian insulating material.The invention particularly relates to be used for boiled kettle, coffee pot or electric cooking pot, steam copper, etc. this parts of (fond chauffant) at the bottom of the heating that is referred to as " concealed " of electric digesting apparatus.The invention still further relates to the manufacturing at the bottom of this heating.Heater block and be attached thereto be provided to heating on flatiron and the steam generator at the bottom of also belong to the field of the invention.

Background technology

In the such equipment of especially boiled kettle, welding of aluminum system heat-transfer device is well-known on the groove of rustless metal.It is the heater block of settling by welding manner equally that the latter has foregoing.

This form of implementation need be passed through the welding of necessity of different phase, and thermal interface may be unsatisfactory on the one hand, and cost price is higher on the other hand.

The improvement that document GB 2 308 537 proposes at this assembling principle, its heat-transfer device has the cabin groove of heater, and tightening of groove wallboard end can the clamping heater block.Heater block can be welded in the groove.

Really, this design can improve the thermo-contact in the heater block and the bottom of a pan, but it implements still quite expensive.

Summary of the invention

An object of the present invention is to realize a kind of electric equipment that has heater block with heating at the end, this equipment has good thermal conductivity at heater block with at heating the end, and can significantly reduce production costs.

Purpose of the present invention can realize with heater block by a kind of electric equipment, these parts have the hollow metal pipe box of being made by the good thermal conductive material of for example aluminium or copper, be provided with in pipe box inside be insulated rings of material around resistance wire, described resistance wire can pass to electric current, it is characterized in that the metal tube cover has and can the plane extends and form the epitaxial part of heat-conducting plate.

Therefore, the present invention is intended to cancel the existence of heat-transfer device as discrete parts, but the pipe box of itself and heater block is made of one, thereby realizes perfect thermo-contact between two parts.

Therefore the hollow metal pipe box is made by having good Heat Conduction Material, for example aluminium or copper or contain the alloy of one of these materials.This condition ratio is more necessary with the material thermal conductivity difference that heater block and heat-transfer device thereof join.

In addition, in order to give heat-conducting plate certain mechanical stability, the thickness of heat-conducting plate is greater than 0.5mm.

A kind of more useful form of implementation according to the present invention, the initial cross-section of heater block is the circle that overall diameter is D, and the width L that forms the epitaxial part of heat-conducting plate is at least 1.5 times of overall diameter D.

The investment cost of the rounded machine that can the limit production heater block of original profile, and remain on standard level.In addition, verified, heat-conducting plate only extends on respect to the bigger width of heater block green diameter, could produce actual effect.

According to another kind of form of implementation of the present invention, heater block is U or C type, and the area of heat-conducting plate equals 40% of the interior external area (surface circonscrite) of heater block at least, so that this area can be given full play to conductive force.

A kind of more useful form of implementation according to the present invention, heat-conducting plate come to form by the mechanical deformation that is placed in the thickening in the hollow metal pipe box.

This mechanical deformation, for example punching press is a kind of operation that is easier to automation, in addition, also is a part of the heater block production process of aforementioned type.Therefore, by changing the initial section bar of making by unlike material, can realize this heat-conducting plate.

Pipe box can take on a different shape.A kind of configuration of uniqueness is, the external shape of pipe box can be such as for example ellipse of suppository shape, and pipe box holds the inner passage of resistance wire can be rounded, and oval maximum axis can be horizontal.The surplus of material is arranged in and is used for realizing heat-transfer device on this axis.Therefore material flatly is driven to the heater block two ends, can cover bigger area like this.In addition, the shape of this symmetry has been simplified pressing step.

Another kind of configuration also can use.The hollow metal pipe box in a tubular form and have base, base is configured to realize the material surplus of heat-conducting plate.Base allows operated pressing tool better to be supported.

For the tool of production is more rationalized, the original shape of metal pipe box is circular valuably, and has thickening with respect to its constant thickness.Profile remains the configuration of standard, and just the thickness of pipe box increases a little.This thickness preferably is 2mm at least.

Mechanical deformation subsequently allows the extruding of material from metal pipe box thickness to the material epitaxy plane.Therefore pipe box has different thickness.At the epitaxial planar position that forms heat-conducting plate, its thickness is less.

According to second kind of execution mode, the special dies of the pipe box of heat-conducting plate by being used for heater block forms.This different enforcement allows to realize a kind of integrated heat-transfer device equally, although its cost is high slightly.We can realize heat-conducting plate by extrusion forming technology equally.

In addition, the invention still further relates to a kind of electric equipment heating component, this assembly has heating plate, and the one side of heating plate contacts with the heat-conducting plate of foregoing heater block.

According to a kind of more useful execution mode of the present invention, heating plate is made by the material of poor thermal conductivity (mauvais), as the rustless metal.This material, especially rustless metal are used as hotting plate the surface widely, and be main because its corrosion resistance and resistance to ag(e)ing are good.

Heater block preferably is welded on the heating plate.This technology often is used to heater block is assembled at heating the end, thereby allows good thermo-contact.

According to a kind of more economical version, heater block can be connected on the heating plate mechanically, for example riveted joint.

According to one and another embodiment and version thereof, the area of heat-conducting plate equal at least heating plate area 65% so that make the heat transmission on the heating plate comparatively even.

Description of drawings

By following at of the present invention be not the detailed description and in conjunction with the accompanying drawings of a circumscribed embodiment, can understand other advantages of the present invention:

Fig. 1 shows the stereogram of an embodiment of heater block pipe box of the present invention;

Fig. 2 shows second embodiment of heater block pipe box of the present invention;

Fig. 3 shows the front elevation of the embodiment of heater block pipe box shown in Figure 2, and enforcement figure of the present invention;

Fig. 4 shows according to the stereogram of the heater block of first embodiment of the invention and heating mantles;

Fig. 5 shows heater block according to first embodiment of the invention and is installed in stereogram on the heating mantles;

Fig. 6 shows the heater block in the first embodiment of the invention and the upward view of integrated heat-transfer device thereof;

Fig. 7 shows along the cutaway view of the three-dimensional form of tool slightly of the acquisition of the A-A line among Fig. 6;

Fig. 8 shows the sectional view of the heater block in the economical version of the present invention.

Embodiment

The present invention relates to a kind of heat-transfer device that becomes one with heater block.This heater block is a kind of pipe box type heater block, and it comprises the hollow metal pipe box, is mounted with resistive heater in the pipe box.

Fig. 1 shows the heater block pipe box of first kind of embodiment according to the present invention, the cross section of hollow metal pipe box 2 and non-common column type, but, be column type in its hollow parts inside at the outside ovalize of pipe box.Therefore the diameter of inner cylindrical cavity is c.Ellipsoidal being characterised in that, the length of two axis is respectively a and b.By way of example, the value of c is 9mm, and the value of a is 11mm, and the value of b is 18mm.

Therefore, according to design shown in Figure 1, for cylindrical shape, its pipe box has the surplus of material at lateral parts.The meaning of the surplus of material is, considering economic factors and the part that exceeds the quata of the material of the appropriate quantity of using when realizing function that pipe box type heater block pursued with respect to the insider.And under the situation of routine, insider's overall diameter commonly used is a, and interior diameter is the tubular sleeve of c.

The tubular sleeve of other shapes also can be used, as long as it has the material surplus, to allow realizing heat-transfer device by the brute force of described material is pushed.

Therefore, Fig. 2 and Fig. 3 show second kind of embodiment of the present invention, and the shape of its middle sleeve 20 is common circle, and overall diameter is e, and interior diameter is d.Yet the bottom of tubular sleeve 20 has for example base 21 of pedestal.With overall diameter is that the pure tubulose of e is compared, and pipe box of the present invention has the material surplus by its base 21, thereby when by proper implements it being suppressed, this material surplus can be used for forming heat-transfer device.

By way of example, the arc length h of the base of this profile is 6mm, and the width g of base is 17mm.The surplus f of base position thickness is 1mm.

As this area was commonly used, as shown in Figure 7, heater block had resistance wire 5, and resistance wire 5 places the hollow parts of metal sleeve, described resistance wire insulated body 7 around.This insulator is mineral insulation preferably, for example oxide, as magnesium oxide, aluminium oxide or zirconia.Also can use boron nitride.As shown in Figure 4, heater block 4 includes 6, two power supply connecting rods 8 of two sealing beads (perles debouchage) equally and exposes by sealing bead 6.

The initial installation steps of heater block can be contrasted traditional step, are about to resistive heater, and magnesium oxide and sealing bead are packed in the sleeve pipe.

Then, according to the present invention, by forcing press suitable squeeze job is carried out in the material surplus, as shown in Figure 3, operated pressing tool 22 is by suitable shape and the pressure B that is produced, make the base distortion of metal sleeve, and by along C to squeeze job to material surplus 21, thereby form the tabular surface 10 that can realize the heat-transfer device function.This operation also can be carried out simultaneously with magnesian compacting operation.

It after this operation the fine finishining program.The embodiment that proposes according to the present invention, as shown in Figure 4 and Figure 5, heater block and heat-transfer device thereof link to each other with at the bottom of the heating, to be used to form electric boiled kettle.Therefore, to form shell 12, shell 12 covers the heated base 14 of heating mantles 16 in its periphery bending in the flat region 10 of heat-transfer device.

As version, the section bar of heater block can just be furnished with heat-transfer device before realizing heater block flat region perhaps can obtain the flat region of heat-transfer device by punching press or special dies.

Fig. 5 shows the binding post 18 that is used to lay heat regulator equally.These binding posts can be realized by 0 895 No. 828 patented technologies of EP of the applicant.

To shown in Figure 7, after extruding, therefore the material surplus allows to obtain more relatively tabular surface as Fig. 4.Therefore, according to the embodiment that proposes, in fact material can extend beyond 30mm from heater block.Its thickness is 1.5mm.

In order to provide notion more clearly, the surplus total amount of material equates at least with total amount according to the required suitable material of the tubular sleeve of traditional method production.

The shape of heat-transfer device depends on that heater block is with respect to the heating configuration at the end.In previous examples, we have highlighted the uniformity of the special section at the heating end.Other the configuration that belongs in the scope of the invention can certainly be considered.Therefore, a kind of star-shaped heat-transfer device, perhaps, the heat-transfer device (heater block can be circular-arc in this example) that has material bridge between the branch of heater block all is admissible.

According to the embodiment that proposes, the area of heat-transfer device probably covers 65% of heating floor space, thereby can avoid heating the point that temperature overheating occurs at the end, and then realizes good temperature homogeneity.When heating was used for the relatively large boiled kettle of convective motion the end, this good homogeneous also was enough to make the liquid thermally equivalent.

Yet,, be necessary to propose the heat-transfer device that floor space is all heated in a kind of general covering for some configuration.Technology described in the invention allows to realize this configuration.

Can by mix, gluing, the husky technology of Crane (clinchage) or, consider cost factor, by riveted joint or screw technology, heater block and integrated heat-transfer device thereof are installed at heating the end.Other technologies also can be used, for example hot rolling system technology.

According to the embodiment that proposes, the heating end, show as the cover 16 that has heated base 14 and chimb 19.According to the embodiment that proposes, the diameter at the heating end is 120mm.

Fig. 8 shows a kind of economic especially embodiment, and heater block 40 comprises the circular cross-section metal sleeve that diameter is D, in metal sleeve, be placed with between two parties insulated body 70 around resistance wire 50.The characteristics of this heater block are that the thickness i of metal sleeve is greater than common thickness, and therefore, the material surplus that realizes allows to realize heat-conducting plate by extruding like this.

Therefore, in similar pressing mode shown in Figure 3, extend to side and form heat-conducting plate 100 in the bottom of pipe box.Like this, the thickness of heater block reduces at the position of heat-conducting plate, but remains unchanged on the top of pipe.

The thickness h of heat-conducting plate 100 is at least 0.5mm, and width L is at least 1.5 times of green diameter D of pipe.According to the embodiment that proposes, the diameter D of metal pipe box is 11mm, and original thickness i is 2mm.After the extruding, the width of heat-conducting plate 100 is 18mm.

Therefore, this initial configuration allows the standard configurations of the heater block of reservation the type, i.e. Yuan Xing metal pipe box.So just can when realizing this heater block, reduce equipment investment.

Therefore, by the present invention, we are by when realize adding the parts pipe box, perhaps when making heater block, enter heat-transfer device is integrated, and have avoided the use of special heat-transfer device.The advantage of its economy beyond any doubt, when heater block linked to each other with the heating end or groove, its thermo-contact was also fairly good.

The present invention can use in plurality of devices, especially liquid heating apparatus: boiled kettle, and coffee pot, steam copper, etc., also be applicable to barbecue type equipment certainly, open-air barbecue rack, electric cooking pot.

In addition, the design can be used for boiler water circulation type coffee pot equally, the heater block binding of this coffee pot and proposition, and use a kind of water-circulating pipe.A kind of like this assembly linked to each other with the heating end, allowed to keep the temperature of coffee pot.By placing the material surplus at heater block and water-circulating pipe position, just can realize the present invention to the extruding of material.Before realizing heater block, this assembly can have the smooth epitaxial part as heat-transfer device equally.

The application of the present invention on flatiron and steam generator can be considered equally.

Claims

1. an electric equipment is with heater block (4,40), comprise the hollow metal pipe box of making by the good thermal conductive material of for example aluminium or copper (2,20), in pipe box, be provided with insulated body (7,70) around resistance wire (5,50), described resistance wire (5,50) can pass to electric current, it is characterized in that metal pipe box (2,20) has the epitaxial part (10) with plane extension and formation heat-conducting plate.

2. as the described heater block of last claim (4,40), it is characterized in that the thickness of described heat-conducting plate (10,100) is greater than 0.5mm.

3. the described heater block of one of claim (40) as described above is characterized in that the initial cross-section of heater block (40) is the circle that overall diameter is D, and the width L that forms the epitaxial part (100) of heat-conducting plate is at least 1.5 times of overall diameter D.

4. the described heater block of one of claim (4,40) as described above is characterized in that heater block (4,40) is U or C shape, the area of heat-conducting plate (10,100) equal at least in the heater block (4,40) external area 40%.

5. the described heater block of one of claim (4,40) as described above is characterized in that, described heat-conducting plate (10,100) forms by the mechanical deformation that is placed in the thickening (21) in the hollow metal pipe box (2,20).

6. as the described heater block of last claim (4,40), it is characterized in that mechanical deformation realizes by stamping technology.

7. as the described heater blocks in one of claim 5 or 6 (4), it is characterized in that it is rounded that the external shape ovalize of hollow metal pipe box (2), pipe box hold the inner passage of resistance wire (5), described oval-shaped largest axis (b) is horizontal.

8. as the described heater blocks in one of claim 5 or 6 (4), it is characterized in that, hollow metal pipe box (20) in a tubular form and have base (21), described base (21) is configured to realize the material surplus of heat-conducting plate (10).

9. as the described heater blocks in one of claim 5 or 6 (40), it is characterized in that the original shape of metal pipe box is circular, and has thickening with respect to its constant thickness.

10. as the described heater block of last claim (40), it is characterized in that the original thickness of pipe box (i) was at least 2mm before distortion.

11. any described heater block (4,40) as in the claim 1 to 4 is characterized in that, the special dies of the pipe box (2,20) of heat-conducting plate (10,100) by being used for heater block (4,40) and forming.

12. an electric equipment heating component comprises heating plate (14), the face of heating plate (14) and the heat-conducting plate (10,100) of any described heater block of claim 1 to 11 (4,40) contact.

13., it is characterized in that heating plate (14) is made by the material of poor thermal conductivity, as the rustless metal as the described heating component of last claim.

14. any described heating component as in claim 12 or 13 is characterized in that heater block (4,40) is welded on the heating plate (14).

15. any described heating component as in claim 12 or 13 is characterized in that, heater block (4,40) is connected on the heating plate (14) with the mechanical system such as riveted joint.

16. any described heating component as in the claim 11 to 15 is characterized in that, the area of heat-conducting plate (10,100) equal at least heating plate (14) area 65%.