JP6818745B2 - Home appliances with a heating plate powered by a thermostat with a thermal cutout - Google Patents

Description

The present invention relates to a household appliance such as an iron having a heating plate powered by a power supply circuit having a thermostat with a thermal cutout, more specifically, a product in which the thermal cutout includes a switch. The switch relates to a product in which a switch is held in a closed position by a transmission mechanism in contact with the switch and a fusible plug in a heat generating plate recess, and the transmission mechanism counteracts the opening of the switch by the action of a return means.

According to Patent Document 1 previously filed by the applicant of the present application, an iron having a heating plate powered by a power supply circuit having a thermostat provided with a thermal cutout is known. In this specification, the thermal cutout consists of a switch, which is held in a closed position by a transmission rod in contact with the switch and the fusible plug in the heat generating plate recess, and the transmission mechanism is of the switch. It resists the opening of the switch by the spring effect of the contact blade.

Such a device has the advantage that by providing a thermostat in which the cutout device is directly incorporated, the assembly process can be reduced, thereby reducing the manufacturing cost of the device.

The cutouts built into the thermostat in this way prevent the iron's heating sole from overheating in the event of a thermostat failure, thereby avoiding the risk of fire, greatly increasing the safety of product use. It will be improved. In fact, when the thermostat is unable to perform its temperature control function, the temperature of the sole rises to the point where it reaches the melting temperature of the fusible plug in the recess of the heating plate. When that temperature is reached, the transmission rod is subject to the pressure exerted by the spring effect of the contact blades and sinks into the molten material, which causes the switch to open.

However, the applicant has noticed in rare cases that the cutout may not work due to the presence of recessed burrs that prevent the transmission rod from sinking into the recess even if the plug melts. In fact, such burrs can occur in the process of providing recesses in the heating plate.

French Patent Application Publication No. 2656952

Therefore, an object of the present invention is to propose a home electric appliance that eliminates the inconvenience. In particular, an object of the present invention is to propose a product including a thermostat equipped with an improved cutout device that guarantees greater safety of use for home appliances.

To this end, the present invention is a household appliance comprising a heating plate powered by a power circuit comprising a thermostat with a thermal cutout, the thermal cutout comprising a switch, the switch of which is a switch. The transmission mechanism is held in the closed position by the transmission mechanism in contact with the fusible plug in the heat plate recess, and the transmission mechanism acts as a return means by melting in the product that opposes the opening of the switch by the action of the return means. A product characterized by comprising at least one melting element that causes the switch to open due to.

Such a product has two molten parts that work on the same one cutout switch, so that if a cutout switch opening failure occurs when the first molten part is melted, a second It has the advantage that the molten part works, which can improve the safety of the product.

Further, by incorporating the second molten component directly into the transmission mechanism, the compact structure of the thermostat can be maintained, and the assembly of the thermostat on the heat generating plate can be performed with the assembly of the thermostat as described in Patent Document 1. Can be kept similar.

According to another feature of the present invention, the transmission mechanism extends over the length between the lower end in contact with the fusible plug and the upper end in contact with the switch, and melting of the melting element results in a reduction in the length of the transmission mechanism.

Such a transmission mechanism has an advantage that it can be manufactured easily and economically, and at the same time, it can guarantee the opening of the cutout switch when the molten element is melted.

According to another feature of the present invention, the melting element is located near the upper end of the transmission mechanism.

Such a feature makes it possible to reduce the risk of being hindered by an external element by bringing the molten element closer to the switch so that the molten element acts more directly on the opening of the switch.

According to another feature of the present invention, the transmission mechanism comprises a rod that contacts the fusible plug and a head that contacts the switch, and the molten element is sandwiched between the rod and the head.

According to another feature of the present invention, the transmission mechanism comprises a guiding means that guides the translational movement between the head and the rod when the melting element melts.

Such a feature can make the transmission mechanism more stable when the thermostat is attached to the heat generating plate.

According to another feature of the present invention, the switch comprises a flexible contact blade made of a material having a spring effect, the contact blade provides a means of returning the switch to the open position, and the upper end of the transmission mechanism is It is supported by a flexible contact blade.

According to another feature of the present invention, the melting element is made of a soluble material having a melting temperature different from that of a fusible plug.

According to another feature of the present invention, the melting element is made of a material having a melting temperature of 300 ° C. or lower.

Such a feature occurs in the transmission mechanism so that when the power supply of the heating plate cannot be cut off due to the melting of the fusible plug, the melting element is melted shortly after the melting of the fusible plug. Allows to take heat loss into account.

According to another feature of the present invention, the thermostat comprises a body to which the thermostat contact blades are fixed, the contact blades extend laterally to the body, and the switch has two independent thermostat contact blades. It has a contact blade, and the contact blade of the switch is also connected to the body.

Such a structure makes it possible to obtain a very compact thermostat with a direct built-in cutout function.

According to another feature of the invention, the product is an iron with a hanging surface that makes thermal contact with the heating plate.

The objects, embodiments and advantages of the present invention will be better understood by the following description of specific embodiments of the invention, provided as non-limiting examples, with reference to the accompanying drawings.
It is a perspective view of the heat generation subassembly of the iron by the specific embodiment of this invention. FIG. 5 is a perspective view of the subassembly of FIG. 1 cut along a vertical plane passing through a thermostat cutout transmission mechanism. It is a top view of the thermostat mounted on the subassembly of FIG. It is sectional drawing of the thermostat by line IV-IV of FIG. 3 when the switch of a cutout is held in a closed position by a transmission mechanism. It is a figure of the thermostat of FIG. 4 when the fusible plug arranged in the recess of the heating plate is melted and the switch of a cutout is in an open position. It is a figure of the thermostat of FIG. 4 when the melting element incorporated in the transmission mechanism is melted and the switch of a cutout is in an open position.

Only the elements necessary for understanding the present invention are shown.

FIG. 1 shows a heating subassembly mounted on an iron, which is a heating plate 2 preferably made of an aluminum casting, in which an electrical resistor 20 is embedded. A hanging surface 1 on which the heat generating plate 2 is placed is provided.

The resistor 20 of the heating plate 2 is fed by a power supply circuit including a thermostat 3 that controls the temperature of the sole 1 before and after the command temperature, and the thermostat 3 is directly fixed to the heating plate 2.

As shown in FIGS. 3 and 4, the thermostat 3 includes, as is obvious, a cylindrical body of XX'axis through which the rivet 30 penetrates in the axial direction, the body of which is a blade constituting the adjustment system of the thermostat 3. A series of insulating spacers 31, 32, 33, and 34 stacked with 4 and 5 sandwiched between them are provided.

The main body supports an upper base plate 35 having an adjusting screw 36 having an lower end supported by a flexible blade 4 fixed to the main body. A second blade 6 is welded to the end 6b of the flexible blade 4. The notches provided in the blades 4 and 6 allow the leaf springs 4a to pass freely.

The blades 4, 4a, 6 constitute a movable assembly with an unstable balance as a whole.

On the other hand, the thermostat 3 includes a rigid blade 5 that is integrated with the thermostat main body 1. The blade 5 and the blade 6 include a contact 5a and a contact 6a, respectively. The bimetal blade 37 is fixed to the base of the thermostat 3 main body and is mechanically connected to the blade 6 by an insulating rod 38.

When the command temperature is reached, the bimetal blade 37 bends back, apparently causing the end 6b of the blade 6 to move, thereby suddenly separating the contacts 5a and 6a provided on the blades 5 and 6, respectively. Produces. At the same time, the power supply to the electric resistor 20 of the sole 2 is cut off.

The user can change the position of the fulcrum on the flexible blade 4 by operating the screw 36, thereby changing the trigger temperature of the thermostat 3.

As can be seen from FIG. 3, the rigid blade 5 further has an electrical connection range 5b that forms an angle of about 45 ° with the portion of the blade 5 having the contact 5a, the thermostat 3 electrically with the flexible blade 4. Further incorporating a thermal cutout device with a switch 7 comprising a connected flexible contact blade 71 with a spring effect and a rigid contact blade 72 having a connection 72B, the flexible blade 71 is below the rigid contact blade 72. A contact 71A is provided which is arranged in the above and is supported by the contact 72A of the rigid contact blade 72.

As shown in FIG. 4, the switch 7 is held in a closed position by a transmission mechanism 8 vertically mounted on a fusible plug 22 housed in a recess 21 provided in the heat generating plate 2, and the fusible plug 7 is held in a closed position. 22 is made of an alloy that can be melted at a temperature of about 390 ° C., which is expected to cut off the power supply of the resistor 20 of the heating plate 2 when the adjustment system of the thermostat 3 fails.

The transmission mechanism 8 comprises a metal rod 81 having a lower end in contact with the fusible plug 22, and further comprising a ceramic head 82 having an upper end in contact with the flexible contact 71 blade of the switch 7, the contact blade 71 being like a spring. The rod 81 is pressed against the fusible plug 22 by being supported by the head 82. The thermostat 3 main body is a lower base plate 39 that extends laterally above the recess 21 and includes a hole through which the rod 81 penetrates, and includes a lower base plate 39 that guides the rod 81 in the transverse direction above the fusible plug 22. ..

More specifically, according to the present invention, the transmission mechanism 8 preferably further comprises a melting element 83 disposed between the head 82 and the rod 81, the melting element 83 having a temperature of the heating plate 2. When the temperature reaches a temperature higher than the melting temperature of the fusible plug 22, for example, when the temperature of the heat generating plate 2 exceeds 400 ° C., the product is manufactured of an alloy that can be melted.

For example, the melting temperature of the melting element 83 is advantageously less than 300 ° C., taking into account the temperature gradient created between the fusible plug 22 and the melting element 83 due to the heat loss that occurs in the transfer mechanism 8. ..

Preferably, the melting element 83 has a lower end supported at the upper end of the rod 81 and has an upper end that engages with a recess in the head 82, and the head 82 has an outer peripheral skirt that extends around the melting element 83.

Advantageously, the outer skirt comprises a lower end having a central opening 82A with which the upper end of the rod 81 engages, the central opening 82A having the head 82 along the longitudinal axis of the rod 81 as the melting element 83 melts. It has a diameter that matches the diameter of the rod 81 so that it can be guided and slide on the upper end of the rod 81. As can also be seen in FIG. 1, the outer peripheral skirt is two vertically elongated openings 82B arranged to face each other, and the opening 82B with which the transverse shaft 84 integrally with the rod 81 is engaged. Further provided, the shaft 84 defines the longitudinal stroke stroke of the head 82 with respect to the end of the rod 81 when the melting element 83 is melted.

At the position shown in FIG. 4, the power supply circuit to the heat generation resistor 20 is closed by the two contact blades 71 and 72, and the power supply to the heat generation resistor 20 is as long as the contact 5a and the contact 5b of the thermostat are in contact with each other. It will be secured.

The operation of the cutout switch incorporated in the thermostat 3 will be described below in relation to FIGS. 5 and 6.

If the thermostat 3 is defective, the temperature of the heating plate 2 will continue to rise rapidly. When the temperature reaches the melting point of the material of the fusible plug 22, the fusible plug 22 melts.

Then, as shown in FIG. 5, the rod 81 of the transmission mechanism sinks into the molten material and descends into the recess 21. As the rod 81 descends, the contact blade 71 flexes downward due to its spring effect, and the contact 71A separates from the contact 72B of the other contact blade 72.

As a result, the power supply to the heat generating resistor 20 built in the heat generating plate 2 is cut off.

If the rod 81 of the transmission mechanism 8 cannot descend into the recess 21 due to a burr around the recess 21, the cutout switch 7 remains closed even if the fusible plug 22 melts. It becomes.

Then, the temperature of the heat generating plate 2 continues to rise until the melting element 83 of the transmission mechanism 8 also reaches the melting temperature due to the heat transferred through the rod 81.

As shown in FIG. 6, melting of the fusible plug 22 results in the head 82 descending along the rod 81 over a few millimeters in the form of a contraction of the length of the transmission mechanism 8, thereby lowering the contact blade 71. The lowering of the is caused especially by the influence of its spring effect, the contact 71a separating from the contact 72a of the other contact blade 72.

Then, the power supply to the heat generating resistor 20 built in the heat generating plate 2 is cut off, the heat generating plate 2 is not heated any more, and the risk of fire is eliminated.

Therefore, the products manufactured in this way have the advantage that the safety improvement can be obtained by the existence of two melting devices arranged in series and cooperate with the same cutout switch. The presence of the second melting device makes it possible to deal with poor opening of the cutout switch due to obstruction of movement of the lower end of the rod in the recess of the heating plate.

In addition, by incorporating a second melting device into the transmission mechanism, the thermostat with cutout can be mounted on the iron's heating plate in the same compact, structurally simple and one-time operation. It can be possible.

It goes without saying that the present invention is described solely as an example and is not limited in any way to the illustrated embodiments. Changes from the viewpoint of the composition of various elements, changes by replacement by equivalent techniques, etc. are still possible without departing from the protected area of the present invention.

Therefore, the present invention is not limited to the field of ironing, and can be applied to all home appliances provided with a heat generating plate whose temperature is controlled by using a thermostat.

Claims (9)

A household appliance having a heating plate (2) powered by a power supply circuit having a thermostat (3) with a thermal cutout, wherein the thermal cutout includes a switch (7) and the switch (7). Is held in the closed position by the transmission mechanism (8) in contact with the switch (7) and the soluble plug (22) in the heat generating plate (2) recess (21), and the transmission mechanism (8) returns. In a product that opposes the opening of the switch (7) by the action of the means (71), the transmission mechanism (8) melts to open the switch (7) by the action of the returning means (71). e Bei at least one fusing element (83) causes,
The transmission mechanism (8) extends over a length between the lower end in contact with the fusible plug (22) and the upper end in contact with the switch (7), and the melting of the melting element (83) is carried out by the transmission mechanism (83). 8) A product characterized by resulting in a reduction in length . The product according to claim 1 , wherein the melting element (83) is arranged near the upper end of the transmission mechanism (8). The transmission mechanism (8) includes a rod (81) that contacts the fusible plug (22) and a head (82) that contacts the switch (7), and the melting element (83) is the rod. The product according to claim 1 or 2 , wherein the product is sandwiched between (81) and the head (82). The transmission mechanism (8) is characterized by including guiding means (84B, 84) for guiding translational movement between the head (82) and the rod (81) when the melting element (83) is melted. The product according to claim 3 . The switch (7) includes a flexible contact blade (71) made of a material having a spring effect, and the contact blade (71) serves as a means for returning the switch (7) to an open position. The product according to any one of claims 1 to 4 , wherein the upper end of the transmission mechanism (8) is supported by the flexible contact blade (71). The product according to any one of claims 1 to 5 , wherein the melting element (83) is manufactured of a soluble material having a melting temperature different from that of the fusible plug (22). The product according to any one of claims 1 to 6 , wherein the melting element (83) is manufactured of a material having a melting temperature of 300 ° C. or lower. The thermostat (3) includes a main body to which the contact blades (4, 5, 6) of the thermostat (3) are fixed, and the contact blades (4, 5, 6) are lateral to the main body. Extending and the switch (7) comprises two contact blades (71, 72) independent of the contact blades (4, 5, 6) of the thermostat (3) of the switch (7). The product according to any one of claims 1 to 7 , wherein the contact blades (71, 72) are also connected to the main body. The product according to any one of claims 1 to 8 , wherein the iron is provided with a hanging surface (1) that is in thermal contact with the heat generating plate (2).

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