JP2018527085A - Home appliances with a heat generating plate powered by a thermostat with thermal cutout - Google Patents

Abstract

A home appliance comprising a heating plate (2) fed by a power supply circuit comprising a thermostat (3) with a thermal cutout, the thermal cutout comprising a switch (7), the switch (7) The transmission mechanism (8) is held in the closed position by the transmission mechanism (8) in contact with the switch (7) and the heat generating plate (2) in the recess (21), and the transmission mechanism (8) is returned to the return means (71). In the product against the opening of the switch (7) due to the action of the at least one melting element (83) causing the opening of the switch (7) due to the action of the return means (71) by melting the transmission mechanism (8). ).

Description

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

  According to Patent Document 1 filed earlier by the applicant of the present application, an iron including a heat generating plate fed by a power supply circuit including a thermostat having a thermal cutout is known. In this specification, the thermal cutout is constituted by a switch, which is held in a closed position by a transmission rod that contacts the switch and the fusible plug in the heating plate recess, and the transmission mechanism is Resist the opening of the switch under the spring effect of the contact blade.

  Such a device has the advantage that by providing a thermostat that directly incorporates the cut-out device, the assembly process can be reduced, thereby reducing the manufacturing cost of the device.

  Cutouts built into the thermostat in this way prevent the iron heating sole from overheating in the event of a malfunction of the thermostat, thereby avoiding the risk of fire occurrence, greatly increasing the safety of product use Be improved. In fact, if the thermostat is unable to perform its temperature regulation function, the temperature of the sole will rise 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 sinks into the melted material under the action of the pressure provided by the spring effect of the contact blade, thereby causing the switch to open.

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

French Patent Application Publication No. 2656952

  Then, the objective of this invention is to propose the household appliances which eliminate the inconvenience. In particular, it is an object of the present invention to propose a product comprising a thermostat with an improved cut-out device that ensures greater use safety for household appliances.

  For this purpose, the present invention is a household appliance comprising a heat generating plate fed by a power supply circuit comprising a thermostat with a thermal cutout, the thermal cutout comprising a switch, the switch being a switch Is held in the closed position by a transmission mechanism that contacts the fusible plug in the heat generating plate recess, and the transmission mechanism is a product that opposes the opening of the switch by the action of the return means. A product characterized in that it comprises at least one melting element which causes the opening of the switch by means of.

  Such a product has two melting parts that work against the same one cut-out switch, so that when the first melting part melts, the second malfunction occurs when the cut-out switch opens. The advantage is that the melted parts work, thereby improving the safety of the product.

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

  According to another feature of the invention, the transmission mechanism extends over a 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 decrease in the length of the transmission mechanism.

  Such a transmission mechanism has the advantage that it can be produced simply and economically, while at the same time ensuring the opening of the cut-out switch when the melting element is melted.

  According to another characteristic of the invention, the melting element is arranged near the upper end of the transmission mechanism.

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

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

  According to another characteristic of the invention, the transmission mechanism comprises guide means for guiding the translational movement between the head and the rod when the melting element is melted.

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

  According to another characteristic of the invention, the switch comprises a flexible contact blade made of a material having a spring effect, the contact blade providing a return means to the open position of the switch, the upper end of the transmission mechanism being Supported by a flexible contact blade.

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

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

  Such a feature occurs in the transmission mechanism to ensure that the melting element is melted shortly after the fusible plug is melted when the fusible melt cannot shut off the power supply of the heating plate. Makes it possible to take into account heat losses.

  According to another feature of the invention, the thermostat comprises a body to which the thermostat contact blade is fixed, the contact blade extends laterally with respect to the body, and the switch is provided in two independent of the thermostat contact blade. A contact blade is provided, 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 cut-out function directly incorporated.

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

Objects, aspects and advantages of the present invention will be better understood from the following description of specific embodiments of the invention, given by way of non-limiting example, with reference to the accompanying drawings.
FIG. 3 is a perspective view of a heat generation subassembly of an iron according to a specific embodiment of the present invention. FIG. 2 is a perspective view of the sub-assembly of FIG. 1 cut along a vertical plane through a thermostat cutout transmission mechanism. It is a top view of the thermostat with which the subassembly of FIG. 1 is equipped. FIG. 4 is a cross-sectional view of the thermostat taken along line IV-IV in FIG. 3 when the cutout switch is held in the closed position by the transmission mechanism. FIG. 5 is a view of the thermostat of FIG. 4 when the fusible stopper disposed in the recess of the heating plate melts and the cutout switch is in the open position. FIG. 5 is a view of the thermostat of FIG. 4 when the melting element incorporated in the transmission mechanism melts and the cutout switch is in the open position.

  Only the elements necessary for understanding the invention are shown.

  FIG. 1 shows a heat generating subassembly mounted on an iron, which is a heat generating plate 2 that is advantageously made of an aluminum casting, with an electrical resistor 20 embedded therein. The heating plate 2 includes a hanging surface 1 on which the heating plate 2 is placed.

  The resistor 20 of the heat generating plate 2 is supplied with power by a power circuit including a thermostat 3 that adjusts the temperature of the sole 1 around the command temperature, and the thermostat 3 is directly fixed to the heat generating plate 2.

  3 and 4, the thermostat 3 has a cylindrical main body of the XX ′ axis through which the rivet 30 penetrates in an axial direction, and the main body 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 interposed therebetween are provided.

  The body supports an upper base plate 35 that includes an adjustment screw 36 having a lower end that is supported by a flexible blade 4 secured to the body. The second blade 6 is welded to the end 6 b of the flexible blade 4. The cuts provided in the blade 4 and the blade 6 can freely pass through the leaf spring 4a.

  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 integral with the thermostat 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 warps to cause the movement of the end 6b of the blade 6 as is obvious, thereby causing a sudden separation of the contact 5a and the contact 6a provided on the blade 5 and the blade 6, respectively. Produce. At the same time, 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 manipulating 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 part of the blade 5 having the contact 5a. It further incorporates a thermal cutout device comprising a switch 7 with a spring-effect flexible contact blade 71 connected and a rigid contact blade 72 having a connection 72B, which is below the rigid contact blade 72. And a contact 71A supported on the contact 72A of the rigid contact blade 72.

  As shown in FIG. 4, the switch 7 is held in the closed position by the transmission mechanism 8 placed vertically on the soluble plug 22 housed in the recess 21 provided in the heat generating plate 2, and the soluble plug No. 22 is manufactured from an alloy that can be melted at a temperature of around 390 ° C. where the resistor 20 of the heat generating plate 2 is expected to be cut off when the thermostat 3 adjustment system fails.

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

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

  In one 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 heat loss occurring in the transmission mechanism 8. .

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

  The outer peripheral skirt preferably comprises a lower end having a central opening 82A with which the upper end of the rod 81 engages, the central opening 82A being adapted so that the head 82 is along the longitudinal axis of the rod 81 when the melting element 83 is melted. It has a diameter adapted to 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 has two vertically elongated openings 82 </ b> B arranged opposite to each other, and the openings 82 </ b> B with which the transverse shaft 84 integral with the rod 81 is engaged. In addition, the shaft 84 defines a longitudinal stroke of the head 82 relative to the end of the rod 81 when the melting element 83 is melted.

  In the position shown in FIG. 4, the power supply circuit to the heating resistor 20 is closed by the two contact blades 71 and 72, and as long as the thermostat contact 5 a and the contact 5 b are in contact, the power supply to the heating resistor 20 is not performed. Secured.

  The operation of the cut-out switch incorporated in the thermostat 3 will be described below in connection with FIGS.

  If the thermostat 3 is defective, the temperature of the heating plate 2 continues 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. When the rod 81 is lowered, the contact blade 71 is bent downward by its spring effect, and its contact point 71A is separated from the contact point 72B of the other contact blade 72.

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

  If the rod 81 of the transmission mechanism 8 cannot be lowered into the recess 21 due to the presence of a flash 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 its melting temperature due to the heat transmitted through the rod 81.

  As shown in FIG. 6, the melting of the fusible plug 22 results in the lowering of the head 82 over a number of millimeters along the rod 81 in a manner that reduces the length of the transmission mechanism 8, thereby lowering the contact blade 71. Is brought about in particular by the effect of its spring effect, so that its contact 71 a moves away from the contact 72 a 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, and the heat generating plate 2 is not further heated, and the risk of fire is eliminated.

  Therefore, the product thus produced has the advantage that an increased safety can be obtained by the presence of two melting devices arranged in series and cooperating with the same cutout switch, The presence of the second melting device makes it possible to cope with an open failure of the cutout switch due to the movement of the lower end of the rod being inhibited in the recess of the heat generating plate.

  In addition, the second melting device is incorporated into the transmission mechanism so that the thermostat with the cutout is as compact and structurally simple as the previous one and attached to the heating plate of the iron in a single operation. Can be possible.

  It will be appreciated that the present invention is described and illustrated by way of example only and is not limited in any way to the illustrated embodiments. Changes from the point of view of the configuration of various elements, changes by replacement using equivalent techniques, and the like are still possible without departing from the protection target area of the present invention.

  Therefore, the present invention can be applied not only to the field of ironing but also to all household appliances including a heat generating plate whose temperature is adjusted using a thermostat.

Claims (10)

  A home appliance comprising a heat generating plate (2) fed by a power circuit having a thermostat (3) with a thermal cutout, wherein the thermal cutout includes a switch (7), the switch (7) Is held in a closed position by a transmission mechanism (8) in contact with the switch (7) and the fusible plug (22) in the recess (21) of the heating plate (2), and the transmission mechanism (8) is restored. In the product that opposes the opening of the switch (7) due to the action of the means (71), the transmission mechanism (8) melts to open the switch (7) due to the action of the return means (71). Product characterized in that it comprises at least one melting element (83) to cause.   The transmission mechanism (8) extends over a length between a lower end in contact with the fusible plug (22) and an upper end in contact with the switch (7), and the melting of the melting element (83) is the transmission mechanism ( The product according to claim 1, which results in a length reduction of 8).   3. Product according to claim 2, characterized in that 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) includes the rod The product according to any one of claims 1 to 3, wherein the product is sandwiched between (81) and the head (82).   The transmission mechanism (8) includes guide 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 4.   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 return means to the open position of the switch (7). The product according to any one of claims 2 to 5, wherein the upper end of the transmission mechanism (8) is supported by the flexible contact blade (71).   The product according to any one of the preceding claims, characterized in that the melting element (83) is made of a soluble material having a different melting temperature than the fusible plug (22).   The product according to any one of claims 1 to 7, characterized in that the melting element (83) is made of a material having a melting temperature of 300 ° C or less.   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) 9. Product according to any one of the preceding claims, characterized in that the contact blade (71, 72) is also connected to the body.   10. Product according to any one of the preceding claims, characterized in that it is an iron with a hanging surface (1) in thermal contact with the heat generating plate (2).

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