CN1237689A - Weight detecting device and microwave oven - Google Patents

Abstract

The present invention provides a weight detecting device for microwave oven, comprising a thrust shaft which is displaced in thrust direction according to weight, a first relative displacement detection member which turns according to displacement of the thrust shaft, a second relative displacement detection member which is turned in response to a rotary driving force from a rotary drive means, and position keeping means for keeping the circumferential positions of the first and second relative displacement detection members, also a rotary displacing device and a hall element are provided. The present invention achieves miniaturization and cost reduction and high-accuracy weight detection.

Description

Weight detecting device and micro-wave oven

The present invention relates to the Weight detecting device of the axial weight of electric detection and use the improvement of the micro-wave oven of this Weight detecting device.

In recent years, in micro-wave oven, used the sensor that temperature and weight are measured, the sensor of using as automatic-cooking.As the Weight detecting device of weight sensor, always adopt variety of ways such as electrostatic capacitive, piezoelectric element formula, at present, electrostatic capacitive becomes main flow.The Weight detecting device of this electrostatic capacitive detects the infinitesimal deflection amount that is produced the output shaft (thrust shaft) of displacement by the weight that is placed on the cooking product on the rotating disk according to the variation of the electrostatic capacitance between parallel plate body.

But, in the Weight detecting device of existing electrostatic capacitive, have oscillating circuit, the electrostatic capacitance of this variable condenser is changed in interelectrode distance.Therefore, the anxiety of the parasitic capacitance that influential wiring graph to printed base plate etc. is produced for tackling this problem, must be guaranteed certain above electrostatic capacitance.In addition, consider the error of accessory size, need certain above interelectrode distance.So, exist that interelectrode subtend area increases and problem that device is maximized.

In addition, this existing Weight detecting device is being used under the situation of micro-wave oven, though can detect the axial addendum modification of rotating disk, but because this rotating disk is rotated the rotating driving device and the Weight detecting device that drive usefulness is the difference independent structures, after with their each self-assembly, makes both combinations again, therefore, assembler's ordinal number is many, and be difficult to make both in conjunction with after the shape miniaturization, often be large scale structure.

Therefore, the objective of the invention is to, provide a kind of Miniaturizable and can carry out the Weight detecting device of stable weight detecting and use the micro-wave oven of this Weight detecting device.

Weight detecting device of the present invention, when thrust shaft because of weight during to variation of axial position, making the 1st and the 2nd relative displacement detect with member is that the center only rotates the regulation rotational angle relatively according to the addendum modification of thrust shaft and with the thrust shaft, is made both position relation maintenances by position holding device.Keep by this action and position, the relative addendum modification that two relative displacements are detected with member quantizes reliably with stable action, is converted into weight by the weight scaler.Specifically, the signal that relative displacement with the 1st is detected be directly proportional with the relative addendum modification of member with respect to the 2nd relative displacement detection with member, for example the signal of the time interval ratio that is directly proportional of relative addendum modification with this is exported as the weight detecting signal, according to this weight detecting signal weight is detected.

And, device as the output weight detection signal, use for example magnet and Hall (ホ-Le) element, the relative displacement detection with the 2nd of magnet that detects with member side according to the 1st relative displacement obtains the weight detecting signal with the relative addendum modification between the magnet of member side.

So, Weight detecting device of the present invention, different with the Weight detecting device of electrostatic capacitive, can not produce the variety of issue that electrostatic capacitive is always had, for example, have influence on the parasitic capacitance that wiring graph on the printed circuit board (PCB) etc. is produced, need guarantee certain above electrostatic capacitance, so that interelectrode subtend area increases and device is maximized.Therefore, can make structure small-sized and can carry out high-precision weight detecting.In addition, keep owing to can carry out reliable position, so but the numerical value of stable supplying addendum modification.

In addition, another Weight detecting device of the present invention, basic structure and move same as described above, promptly, when thrust shaft because of weight during to variation of axial position, it is that the center only rotates the regulation rotational angle relatively according to the addendum modification of thrust shaft and with the thrust shaft that the 1st and the 2nd relative displacement detects with member.In addition, in the application of force that axially is subjected to force application apparatus, its end face contacts with datum level all the time with member in the described the 1st and the 2nd relative displacement detection.Therefore, the 1st and the 2nd relative displacement detection begins (to the detection action beginning of weight) with the action of member, owing to be the position of all-the-time stable ground from mutual and datum level butt, so can carry out high-precision weight detecting.In addition, above-mentioned structure, that is, when making the textural association relevant with the position maintenance, accuracy of detection just increases.

In addition, this Weight detecting device is used as the micro-wave oven of the Weight detecting device that the weight that is positioned over the cooking product on the rotating disk is measured, weight detecting partly can be set as small-sized structure, thereby can obtains the miniaturization of micro-wave oven integral body.Especially, the 2nd relative displacement detects uses member, when double as will come from the output gear of the deceleration wheels that the revolving force that makes rotating disk rotation drive the drive source of usefulness slowed down, owing to can make rotating driving device and weight detecting sectoral integration, so partly compare with weight detecting for the traditional structure that separates with rotating driving device, can obtain miniaturization, in the time of also the assembler can being reduced.

Fig. 1 is the sectional view of expression Weight detecting device example of the present invention.

Fig. 2 is the exploded perspective view of Weight detecting device shown in Figure 1.

Fig. 3 is a upward view of seeing the Weight detecting device shown in Fig. 1 from the below of Fig. 1.

Fig. 4 is a vertical view of seeing the Weight detecting device shown in Fig. 1 from the top of Fig. 1.

Fig. 5 is that detailed description Fig. 1 and the 1st relative displacement shown in Figure 2 detect the stereogram with member.

Fig. 6 is that detailed description Fig. 1 and the 2nd relative displacement shown in Figure 2 detect the stereogram with member.

Fig. 7 is the design sketch of expression as the force application spring of the position holding device in the Weight detecting device of the invention process form, promptly be with rotating disk be set as can the occasion of two-way rotation in when the CW direction is rotated and the result of the gravimetry when the CCW direction is rotated, expression actual weight with measure scaled value the figure of how many gaps arranged, figure (A) is the occasion of configuration force application spring, and figure (B) is the figure that does not dispose the occasion of force application spring.

Fig. 8 is that the 1st relative displacement of explanation Weight detecting device shown in Figure 1 detects with the graph of a relation of the relative displacement detection with the 2nd of member with member, figure (A) is the front view when not acting on the load of rotating disk, and figure (B) is the front view when acting on the load of rotating disk to greatest extent.

Fig. 9 is the cutaway view along IX-IX among Fig. 1.

Figure 10 is the figure of the expression employed helical spring characteristic of Weight detecting device shown in Figure 1.

Figure 11 is the stereogram of the sheet spring of expression Weight detecting device shown in Figure 1.

Figure 12 be in the expression Weight detecting device shown in Figure 1 as the figure of the effect of the sheet spring of force application apparatus, being presentation graphs (A) is actual weight separately that does not dispose sheet spring occasion and the Error Graph of measuring scaled value for occasion, the figure (B) of configuration sheet spring.

Figure 13 is that the relative displacement with the 2nd of each magnet that the 1st relative displacement of explanation Weight detecting device shown in Figure 1 detects with member side detects the position relation of each magnet of using member side and the figure of Hall element IC configuration, figure (A) is the figure when being illustrated on the rotating disk service load not, and figure (B) is the figure that is illustrated in effect busy hour on the rotating disk.

Figure 14 is the figure of the output signal of the expression employed Hall element IC of Weight detecting device shown in Figure 1, figure (A) is the figure of the output signal when being illustrated on the rotating disk service load not, and figure (B) is the figure that is illustrated in the output signal of effect busy hour on the rotating disk.

Figure 15 acts on load on the Weight detecting device shown in Figure 1 to rotating disk to be made as transverse axis, the 1st relative displacement is detected the figure that value (phase difference of=magnet A, B) that time interval of exporting with the Hall element IC of the magnet of member side with respect to the 2nd relative displacement detection with the Hall element IC output of the magnet of member side represents by percentage is made as the longitudinal axis.

Figure 16 acts on load on the Weight detecting device shown in Figure 1 to rotating disk to be made as transverse axis, the 2nd relative displacement is detected the figure that value (phase difference of=magnet A, B) that time interval of exporting with the Hall element IC of the magnet of member side with respect to the 1st relative displacement detection with the Hall element IC output of the magnet of member side represents by percentage is made as the longitudinal axis.

Below, the example of the invention process form is described in conjunction with Fig. 1 to Figure 16.In this example, the example that just Weight detecting device is used for micro-wave oven describes.When being used for micro-wave oven, as previously mentioned, the addendum modification of rotating disk of placing cooking product as the signal of expression cooking product weight and take out, is controlled the irradiation time that determines microwave etc. according to the signal of representing this weight.

At first, by Fig. 1 to Fig. 6 overall structure is described.Weight detecting device 1 is divided several major parts, comprising: make rotating disk 11 rotations and make the described later the 1st and the 2nd relative displacement detect the rotating driving device 12 that rotates with member 42,43 and thrust shaft 41 one; To the weight detecting portion 13 that the variation of axial position amount of rotating disk 11 detects, these each structural elements are contained in 1 metal housing 14.Housing 14 is made of enclosure body 14a and case lid 14b, becomes by the bottom surface of enclosure body 14a to detect the configuration of using member 42,43 with two inner faces of case lid 14b from above-below direction clamping the 1st and the 2nd relative displacement.That is, the bottom surface of enclosure body 14a and case lid 14b become two top boards of housing 14.

Rotating driving device 12 comprises: as the motor (using synchronous motor here) 20 of drive source; Detect with member 43 with the revolving force deceleration of this motor 20 and to the 2nd relative displacement that becomes the 1st gear the 31, the 2nd gear the 32, the 3rd gear 33, output gear that rotating disk 11 transmits as the deceleration wheels; Prevent the anti-down bull stick 34a of motor 20 reversings and the anti-down bull stick rotation gear 34 that disposes with the coaxial shape of anti-down bull stick 34a.In addition, anti-down bull stick 34a and anti-down bull stick rotate with gear 34 in the application of force that axially is subjected to spring 34b.

Motor 20 comprises coil 21, rotor 22, fixed axis 23, be fixed on pinion 24 on the rotor 22 and dividing plate 25 etc.In addition, at the root of pinion 24, be provided with when rotor 22 reversing and anti-down bull stick 34a butt is prevented projection 24a, the 24a of usefulness to the reversing of rotor 22.Therefore, under the situation of positive direction rotation, the projection 24a of rotor 22 does not combine with the projection 34c of anti-down bull stick 34a at rotor 22, and rotor 22 can freely rotate, and under the situation of opposite spin, the projection 34c of anti-down bull stick 34a meets projection 24a and stops the rotation of rotor 22.

In addition, the 1st gear 31 and the 2nd gear 32 are installed between dividing plate 25 and the case lid 14b by axle 31a, 32a respectively, and the 3rd gear 33 is installed between enclosure body 14a and the case lid 14b by axle 33a.In addition, the utmost point tooth that constitutes motor 20 stators is established for thirty years of age to rotor 22 from enclosure body 14a, and for covering the remainder that forms this utmost point tooth, label 26 is attached on the enclosure body 14a.

The primary structure key element of weight detecting portion 13 is: an end be fixed on rotating disk 11 the center, according to act on the rotating disk 11 weight and to the thrust shaft 41 of variation of axial position; Detect with member 42,43 in conjunction with the 1st and the 2nd relative displacement that is provided with this thrust shaft 41; Make described 2 to detect with what member 42,43 relatively rotated the displacement ormal weight relative to displacement and to rotate displacement device 44 according to the addendum modification of thrust shaft 41; Make the 1st and the 2nd relative displacement detect the force application spring 45 that keeps usefulness with member 42,43 in the position of direction of rotation relation as position holding device; Weight detecting signal output apparatus described later; Be configured in the helical spring 46 of thrust shaft 41 front.In addition, by the signal of weight detecting signal output apparatus output, utilize the weight scaler (diagram is omitted) that constitutes by microcomputer and be converted into weight.

In addition, the 1st and the 2nd relative displacement detects and is coaxial over the ground mutually with member 42,43 and is arranged on the thrust shaft 41.And, the 1st detects with member 42 when rotating according to the axial displacement of thrust shaft 41 relative to displacement, the 2nd detects relative to displacement and not to rotate because of the axial displacement of thrust shaft 41 with member 43, rotates from the rotary driving force of rotating driving device 12 by being subjected to.That is, it is the parts that constitute the deceleration wheels of rotating driving device 12 that the 2nd relative displacement detects with member 43, the output gear that double as combines with another gear.

Rotate displacement device 44, when make the 1st and the 2nd relative displacement detect with member 42,43 combine with thrust shaft 41, thrust shaft 41 is during to variation of axial position, making the 1st, to detect with member 42 relative to displacement be that the regulation rotational angle is only rotated at the center according to the addendum modification of thrust shaft 41 and with thrust shaft 41, when the 2nd relative displacement detects when being subjected to rotating from the driving force of rotating driving device 12 with member 43, this revolving force can be passed to thrust shaft 41.This rotation displacement device 44 comprises: detect oblique groove 42b, the 42c that forms with on the member 42 in the 1st relative displacement; Detect axial groove 43b, the 43c that forms with on the member 43 in the 2nd relative displacement; Be installed on the thrust shaft 41, make the 1st and the 2nd relative displacement detect with member 42,43 the pin 44a of the overlapping separately part of embedded groove 42b, 43b and groove 42c, 43c when chimeric.These detailed structure as described later.

Force application spring 45 is made of helical spring, becomes the position that the 1st and the 2nd relative displacement is detected with the direction of rotation of member 42,43 and concerns the position holding device that is kept usefulness.When carrying out the position maintenance without this force application spring 45, when gravimetry, just produce error.

Promptly, when motor 20 being set as can be to the structure of two directions rotations the time, if do not dispose the force application spring 45 that above-mentioned position keeps usefulness, then shown in Fig. 7 (A), will produce error to the occasion of clockwise direction (to call the CW direction in the following text) rotation with to the mensuration scaled value of the occasion of (to call the CCW direction in the following text) rotation counterclockwise to rotating disk 11.

On the contrary, even can be to the structure of two directions rotations, if allocation position keeps the force application spring 45 of usefulness, then as Fig. 7 (B) shown in, just can be to rotating disk 11 to the occasion of CW direction rotation with to the mensuration scaled value generation error of the occasion of CCW direction rotation.In addition, shown in this example, even become under the situation of direction rotation motor 20 being set as to direction rotation, rotating disk 11, the circumferential position that also can utilize this force application spring 45 to keep the 1st and the 2nd relative displacement to detect with member 42,43 accurately concerns.

In addition, above-mentioned position holding device specifically as shown in Figure 9, detecting with member 43 with the 2nd relative displacement by force application spring 45 is that benchmark is used member 42 application of forces to circumferentially the 1st relative displacement being detected, and makes the relative displacement with the 1st of pin 44a as shown in Figure 8 detect limit 42c1, the 42b1 that is rendered as groove 42b, 42c one side with the butt position W1 separately that forms 1 couple groove 42b, groove 42c on the member 42.On the other hand, pin 44a during rotating disk 11 rotation and the butt position W2 of groove 43b, 43c are positioned at limit 43b2, the 43c2 of groove 43b, 43c opposite side all the time.Thus, pin 44a is not suppressed to and can becomes flexible in two grooves that overlap, thereby the circumferential position relation that the 1st and the 2nd relative displacement detects with member 42,43 is always remained equal state.

Two ends are supported under the state of this force application spring 45 in being compressed in storage part, and storage part by with thrust shaft 41 by the 1st relative displacement that on same radius, forms at center detect with the projection 51d of member 42 and the 2nd relative displacement detection with member 43 deposit wall 52d and push projection 52e is constituted.Thus, force application spring 45 is that benchmark applies elastic force to circumferentially the 1st relative displacement being detected with member 42 with the 2nd relative displacement detection with member 43 just.This elastic force occurs in the 1st relative displacement detection with on the member 42 by making to the axial power F1 of datum level side described later with pin 44a butt.Therefore, the 1st relative displacement detects axial position with member 42 and also is always the certain position position of datum level butt (=with).

In addition, the weight detecting signal output apparatus will be exported as the weight detecting signal with the signal of the relative addendum modification of member 42,43 according to the 1st and the 2nd relative displacement detection.This weight detecting signal output apparatus comprises as shown in Figure 9: at 3 magnet B1, the B2s, the B3 that become detected body of the 1st relative displacement detection with member 42 side settings; At 3 magnet A1, the A2s, the A3 that become detected body of the 2nd relative displacement detection with member 43 side settings; And the Hall element IC47 that becomes detector that the magnetic force that these magnets B1～B3, A1～A3 are produced is transformed into the signal of telecommunication.About these detailed structure as described later.

Now describe the weight detecting portion 13 of this structure again in detail.As shown in Figure 1, thrust shaft 41, as mentioned above like that one end (rear end) in conjunction with or be fixed on the rotating disk 11, when the revolving force with motor 20 passes to rotating disk 11, because of cooking product are placed on the rotating disk 11, so with rotating disk 11 to axial decline.And,, the lining 48 and the lid member 49 of pushing helical spring 46 usefulness is installed in the other end (front end) side of this thrust shaft 41.Helical spring 46 use cross sections be tetragonal we be referred to as the helical spring of what is called " square wire rod helical spring ", the elastic force that will overcome the power that thrust shaft 41 desires descend acts on thrust shaft 41.That is, thrust shaft 41 is by helical spring 46 supporting, according to weight overcome helical spring 46 restoring force and to variation of axial position.

In addition, as shown in Figure 5, the 1st relative displacement detects and is cylindric with member 42, and heart portion is formed with the hole 42a that thrust shaft 41 is connected therein.And,, be formed with a pair of groove 42b, 42c on the relative position clipping central shaft in its side cylindrical portions may.This groove 42b, 42c, central axis direction inclination predetermined angular ground forms relatively.In addition, in the outside of side cylindrical portions may, be provided with the magnet filling department 51a, 51b, the 51c that are used for loading magnet B1, B2, B3 with 120 ° of arranged spaced.On the magnet filling department 51a of these magnet filling departments 51a, one of 51b, 51c, be provided with and a distolateral projection 51d who combines who the 1st and the 2nd relative displacement detection is kept the force application spring 45 of usefulness with the position relation of the direction of rotation of member 42,43.In addition, another of this force application spring 45 is distolateral, be seated in the storage part, this storage part by be located at the 2nd relative displacement detect with on the member 43 deposit wall 52d and push projection 52e is constituted.

On the other hand, as shown in Figure 6, the 2nd relative displacement that also becomes output gear detects and is an end with member 43 end other end is arranged is the cylindric of opening, and its internal diameter is a bit larger tham the external diameter that the 1st relative displacement detects usefulness member 42, has the inner cylindrical 43a of formation concentric circles in inside.The external diameter of this inner cylindrical 43a is slightly smaller than the 1st relative displacement and detects the internal diameter of using member 42, in its side cylindrical portions may, is formed with groove 43b, the 43c of a pair of opening vertically on the relative position at the central shaft that clips cylinder.

The central part that bottom end side is arranged that detects with member 43 in this 2nd relative displacement is formed with the hole 43d that thrust shaft 41 is connected.In addition, the lateral surface that detects with member 43 in the 2nd relative displacement is formed with gear, with the 3rd gear 33 engagements of rotating driving device 12, also plays the effect as output gear.

This 2nd relative displacement detects distolateral with member 43, with sheet spring 50 butts that become metal plate-shaped springs member shown in Figure 11.Sheet spring 50 is configured between the inner face that becomes case lid 14b of the 1st and the 2nd relative displacement detection with member 42,43 and housing 14 1 sides' top board.As shown in figure 11, this sheet spring 50 comprises: be the flat annulus 50a of portion; 10 50b of spring portion that extend laterally agley to case lid 14b side slightly than the outer peripheral portion of the 50a of this annulus portion, by the inner face butt of each 50b of spring portion and case lid 14b, thereby annulus portion 50 just uses member 42 to the enclosure body 14a side application of force with member 43 and by this member 43 to the 1st relative displacement detection to the 2nd relative displacement detection.So, sheet spring 50 becomes the 1st and the 2nd relative displacement detection member 42,43 force application apparatus to axial force distribution.

And, the 1st relative displacement detects with the relative displacement with the 2nd of member 42 and detects with member 43, make and make the 1st relative displacement detect the relative displacement in the end with intake section with groove 42b, the 43c of member 42 to detect with the open end of member 43 relatively, the 1st relative displacement detected with member 42 insertions the 2nd relative displacement detection use in the member 43 with the 2nd.Thus, the 2nd relative displacement detects inner cylindrical 43a with member 43 becomes and inserts the 1st relative displacement and detect the state of using member 42 interior.

In addition, be formed with the outstanding columnar protuberance 43e (with reference to Fig. 2) to foreign side, this columnar protuberance 43e and sheet spring 50 butts in the bottom that has that the 2nd relative displacement detects with member 43.Thus, the 2nd relative displacement detects the application of force that is subjected to elastic force F2 with member 43 to the bottom surface side of enclosure body 14a.And, detect the open end side of using member 43 in the 2nd relative displacement, between detecting with member 42,43, the relative displacement with the 1st and the 2nd of inner face of enclosure body 14a disposes flat packing ring 54.So, the 2nd relative displacement detects the application of force that just is subjected to sheet spring 50 with member 43 1 sides, and opposite side is pushed down by packing ring 54, thereby the action of above-below direction is limited.

In addition, the 1st relative displacement detection detects with member 43 with member 42 by the 2nd relative displacement and utilizes elastic force F2 to be pressed towards packing ring 54 sides.In addition, the 1st relative displacement detects with member 42, as previously mentioned, also is crushed on the packing ring 54 by elastic force F1 that force application spring 45 produced.

So, when on the rotating disk 11 during zero gravity (A-stage) and when placing cooking member on rotating disk 11, just relative with the 1st and the 2nd displacement of packing ring 54 detects uses 42,43 while of member butt.Promptly, this packing ring 54 is state and when cooking in the early stage, become the 1st and the 2nd relative displacement to sheet spring 50 application of forces that are subjected to force application apparatus and detect the datum level that the end face with member 42,43 is supported, the 1st and the 2nd relative displacement detection is just being done relative displacement in the weight that basis on this datum level is applied on the rotating disk 11 with member 42,43.Utilizing this structure, is stable because of weight causes both relative addendum modifications, can carry out free from error weight detecting reliably.

In addition, detect the shape of making while and packing ring 54 butts with each end face of member 42,43 though be subjected to the 1st and the 2nd relative displacement of sheet spring 50 application of forces, but, both can be only the 1st relative displacement be detected with member 42 and made structure with packing ring 54 butts, also can be only the 2nd relative displacement detection be made structure with packing ring 54 butts with member 43.When only the 2nd relative displacement being detected when making shape with packing ring 54 butts with member 43, the 1st relative displacement detects elastic force F1 and packing ring 54 butts that usefulness member 42 also leans on force application spring 45.In addition, though packing ring 54 detects with member 42,43 rotation and being provided with smoothly for the 1st and the 2nd relative displacement, also it can be cancelled, direct bottom surface with enclosure body 14a is as datum level.

This example is, utilizes 45 pairs the 1st of sheet spring 50 like this and force application springs and the 2nd relative displacement to detect with member 42,43 to axial force distribution, becomes the structure of packing ring 54 both end faces of supporting that are used as datum level.Utilize this structure, have effect as shown in Figure 12.Figure 12 shows that make actual weight is that separately weight divides and is placed on the result who carries out weight detecting on the rotating disk 11 3 times in 7 weights (for whenever differing the Different Weight of 1kg) of 1～7kg, the sheet spring is disposed in Figure 12 (A) expression 50 pairs the 1st and the 2nd relative displacement detection member 42,43 occasions to axial force distribution, the actual weight and mensuration scaled value of sheet spring 50 occasions do not disposed in Figure 12 (B) expression.

Two curve maps according to Figure 12, under the situation of " the sheet spring is arranged " shown in Figure 12 (A), actual weight is roughly consistent in 3 experiments with the mensuration scaled value, substantially error free, on the contrary, under the situation of " the no sheet spring " shown in Figure 12 (B), actual weight produces error with the mensuration scaled value in whole 3 experiments.From this measurement result, detect the packing ring 54 that makes it and become datum level to axial force distribution with member 42,43 butt reliably by 50 pairs the 1st of sheet springs and the 2nd relative displacement, the Weight detecting device of this example has the effect that can carry out more accurate weight detecting.

In addition, as shown in Figure 2, the rectangular-shaped crosscut of the central shaft of thrust shaft 41 is made the two ends of pin 44a highlightedly pin 44a is installed on the thrust shaft 41 to both sides (about being called).And, ledge about this pin 44a, engage with axial groove 43b, the 43c that form on the inner cylindrical 43a that detects in the 2nd relative displacement with member 43, engage with forming oblique groove 42b, 42c on the member 42 simultaneously with in the 1st relative displacement detection.In addition, the end of pin 44a is fastened in the slit 43f as shown in Figure 6, and this slit 43f clips the 1st relative displacement detection and disposes with groove 43 subtends that form on the 2nd inner cylindrical 43a of relative displacement detection with member 43 with member 42.

The front end of this thrust shaft 41 passes packing ring 54 and bearing components 53a and arrives the lid member 49 that is configured in the outstanding cylindrical portion 14c from enclosure body 14, the action that helical spring 46 is compressed.At this moment, the front end of this thrust shaft 41 by lining 48 and with lid member 49 butts, lining 48 and become the state that rotates freely relatively.And the rear end side of this thrust shaft 41 is passed bearing components 53b and outstanding to foreign side from case lid 14b, engages or is fixed on the rotating disk 11.

Thrust shaft 41 is mounted with this state.Promptly, as previously mentioned, the relative displacement detection with the 2nd of pin 44a that is installed on this thrust shaft 41 uses groove 43b, the 43c of member 43 sides (with the same direction of central shaft, promptly axially form) fasten, groove 42b, 42c (central axis direction is formed slopely predetermined angular relatively) that simultaneously relative with the 1st displacement detects with member 42 sides fasten.Therefore, when action that thrust shaft 41 is depressed, pin 44a desires to move downwards relative to groove 42b, the 42c of displacement detection with member 42 with the 1st by the 2nd groove 43b, the 43c that detects with member 43 sides relative to displacement.At this moment, because the 2nd relative displacement detection is restricted with the action of the direction of rotation of member 43, and groove 43b, 43c become and axial same state, so can not rotate.On the other hand, the 1st relative displacement detects with member 42, moves downwards and be that middle mind-set direction of rotation is moved with thrust shaft 41 by pin 44a.Now be described according to Fig. 8.

The STA representation thrust shaft 41 of Fig. 8 (A) in the early stage in the state (not making cooking product be placed on state on the rotating disk 11) the relative displacement of pin 44a with the 1st and the 2nd detect with separately groove 42b, the 42c of member 42,43 and the relation of 43b, 43c, Fig. 8 (B) expression is placed on the rotating disk 11 cooking product and the thrust shaft 41 relative displacement detection with the 1st and the 2nd of pin 44a separately groove 42b, the 42c of member 42,43 and relation of 43b, 43c in the state after the decline to greatest extent.Can learn also that from this Fig. 8 (B) when the product of will cooking were placed on the rotating disk 11, the 1st detected relative to displacement and to rotate predetermined angular with member 42, groove 42b, 42c just on circumference to circumferential only mobile (rotation) distance L.

So, when load is applied on the rotating disk 11, the thrust shaft 41 real estate position (declines) of changing that is directly proportional with this load, thereupon, the 1st can only move to direction of rotation with ultimate range L with member 42 relative to displacement detection.

In addition, as shown in Figure 1, under the situation that these rotating disk 11 rotations are driven, if motor 20 is set as "on" position, then its revolving force transmits to the 3rd gear 33 from the 1st gear 31.In addition, being delivered to the 2nd relative displacement of meshing with the 3rd gear 33 detects with member 43.If the 2nd relative displacement detects with member 43 rotations, then its revolving force passes to thrust shaft 41 by aforesaid butt position W2 by pin 44a, thus, can make rotating disk 11 rotations.

So, when thrust shaft 41 during to variation of axial position, pin 44a with the 1st relative to displacement detect with member 42 side settings groove 42b, 42c, the 2nd relatively the displacement detection make the 1st to be that the regulation rotational angle is only rotated at the center with member 42 according to the addendum modification of thrust shaft 41 and with thrust shaft 41 with groove 43b, the 43c of member 43 side settings relative to the displacement detection.And when the 2nd relative displacement detection was rotated in the driving force that is subjected to rotating driving device 12 with member 43, pin 44a etc. carried out the revolving force of motor 20 to be passed to the action of thrust shaft 41.That is, pin 44a etc. constitutes aforesaid structure as the displacement direction-changing device.

Below, just detect the device that will be exported with the corresponding signal of telecommunication of payload that is applied on the rotating disk 11 with the relative motion of member 43 with respect to the 2nd relative displacement detection, promptly weight detection signal output device described with member 42 according to the 1st relative displacement.

As shown in figure 13, detect with on the member 42 in the 1st relative displacement, same plane ground uniformly-spaced disposes 3 magnet B1, B2, B3.Leave 120 ° between described each magnet.In addition, detect with on the member 43 in the 2nd relative displacement, same plane ground uniformly-spaced disposes 3 magnet A1, A2, A3.Leave 120 ° between described each magnet.And, the the 1st and the 2nd relative displacement is detected resemble with member 42,43 above-mentioned under the state of the coaxial shape of chimeric one-tenth, between 6 above-mentioned magnet A1, A2, A3, B1, the corresponding magnet of B2, B3, that is, magnet A1 and magnet B1, magnet A2 and magnet B2, magnet A3 and magnet B3 leave 33.24 ° of ground respectively and are configured to same plane.

And near this magnet, fixed configurations has the Hall element IC47 that magnetic force is transformed into signal of telecommunication output.Give prominence to the outside of housing 14 by being located at the hole (diagram is omitted) on the enclosure body 14a bottom surface terminal part of this Hall element IC47, and this ledge is installed on the printed base plate 55 (with reference to Fig. 3), and is covered by support 56.In addition, binding post 57 elements such as grade also are installed on this printed base plate 55.

Figure 13 (A), (B) are the figure that the position of described each magnet A1, A2, A3, magnet B1, B2, B2, Hall element IC47 relation is described, for ease of understanding, made ideograph, the Fig. 1 that uses in representing yet in addition to illustrate at present is to the part of structure shown in Figure 9.

Magnet A1, A2, A3 and magnet B1, B2, B3 dispose at grade differently.That is, magnet A1, magnet B1, magnet A2, magnet B2, magnet A3, magnet B3 are mutually different configuration, and configuration at grade separately.In addition, Figure 13 (A) expression and the corresponding position of the state of Fig. 8 (A) relation are the thrust shaft 41 position relations of state (cooking product are not placed on the state on the rotating disk 11) in the early stage.In addition, Figure 13 (B) represents and the corresponding position of the state of Fig. 8 (B) relation that the cooking product of expression 7kg are placed on the position relation of thrust shaft 41 state after descending to greatest extent on the rotating disk 11.

In Figure 13 (A), be spaced apart 33.24 ° at 1 group of magnet (for example magnet A1 and magnet B1) of approximated position configuration.And when cooking product (being set as 7kg) were placed on thrust shaft 41 on the rotating disk 11 and become state after descending to greatest extent, the 1st rotated to greatest extent with member 42 and becomes the such state of Fig. 8 (B) relative to the displacement detection.So shown in Figure 13 (B), the 1st magnet B1, B2, the B3 that detects with member 42 relative to displacement moves to circumferential 20 ° respectively to greatest extent.Therefore, as mentioned above, state leaves 53.24 ° being spaced apart of 1 group of magnet (for example magnet A1 and magnet B1) of approximated position configuration in the early stage.

In this structure, describe with regard to its action.At first, under the product of will not cooking were placed on situation on the rotating disk 11, it was the such state of Fig. 8 (A) with the pass of member 43 that the 1st relative displacement detects with the relative displacement detection with the 2nd of member 42.Under this state, magnet A1, A2, A3 and magnet B1, B2, B3 are the such position relation of Figure 13 (A).

Under this state, if motor 20 rotation, then the 2nd relative displacement detects with member 43 and also begins to rotate, and obtains output as 14 (A) from Hall element IC47.That is to say, by Hall element IC47 with approaching magnet between the time interval output signal that is directly proportional of angle.That is, if be conceived to the part of magnet A1, B1, A2, leave 120 ° between magnet A1, A2, the angle between magnet A1, B1 is 33.24 °, and the angle between magnet B1, A2 is 86.76 °.

Here, when only considering that the 2nd relative displacement detects with magnet A1, A2 in the member 43, A3, rotation along with rotating disk 11, if the signal As1 of the Hall element IC47 that will produce from magnet A1 to and the signal As2 of the Hall element IC47 that produces of magnet A2 time (time of the centre of time width each signal) be made as t, then should time t constant, become and 120 ° of time corresponding of angle.Therefore, under the product of will not cooking are placed on situation on the rotating disk 11, between magnet A1 and magnet B1, earlier by Hall element IC47 output signal As1, when through the time with 33.24 ° of time corresponding of angle=0.28t, output signal Bs1.In addition, magnet A2 is also identical with this relation with the relation of magnet B2 and magnet A3 and magnet B3.

Then, between magnet B1 and magnet A2, by Hall element IC47 output signal Bs1, when through the time with 86.76 ° of time corresponding of angle=0.72t, output signal As2.In addition, magnet B2 is also identical with this relation with the relation of magnet A3 and magnet B3 and magnet A1.

In addition, as method, as previously mentioned, the length between the center (center of the deration of signal) of signal is carried out instrumentation by the time instrumentation between the signal of Hall element IC47 output.This is because the width of the output signal of Hall element IC47 might change with temperature, for tackling this problem, to carrying out instrumentation in the output signal in the heart.

On the other hand, when on rotating disk 11, place some cooking product, when beginning to cook, rotating disk 11 begins rotation, and thrust shaft 41 because of the weight of cooking product with rotating disk 11 declines.

Thus, the 1st detects relative to displacement and to rotate with the slippage of rotating disk 11 with member 42 with being directly proportional, and angle changes between the magnet between this adjacent magnet of the magnet B1 relative with magnet A1, the magnet B2 relative with magnet A2.At this moment, because rotating disk 11 is in rotation status, so by Hall element IC47 output and the corresponding signal As1 of magnet A1, with the corresponding signal Bs1 of magnet B1, with the corresponding signal As2 of magnet A2, this and each magnet passes through corresponding signal with the corresponding signal Bs2 of magnet B2.But, the time interval of signal As1 and the Bs1 of this moment during than aforesaid A-stage the time interval=0.28t is long.When in addition, the time interval of signal Bs1 and As2 is than aforesaid A-stage the time interval=0.72t is short.

For example, as extreme example, when the cooking product that make 7kg were placed on the rotating disk 11, the relative displacement detection with the 1st of magnet A1, A2, A3 that the 2nd relative displacement detects with member 43 sides was the such position relation of Figure 13 (B) with magnet B1, the B2 of member 42 sides, the pass of B3.Promptly, the relative displacement with the 2nd of magnet that detects with member 42 sides in the 1st relative displacement detects in the A-stage of the magnet of using member 43 sides, (for example be between the magnet of approximated position angle, angle between the magnet of magnet A1 and magnet B1) expands 53.24 ° to, with at the magnet of not approaching position configuration (for example, magnet A2 for magnet B1) angle narrows down to 66.76 °, therefore, obtains the such output of Figure 14 (B) from Hall element IC47.

Also can learn from Figure 14 (B), with the corresponding signal As1 of magnet A1 and with time interval of the corresponding signal Bs1 of magnet B1, with respect to being about 44% with the corresponding signal As1 of magnet A1 with the time interval t of the corresponding signal As2 of magnet A2, i.e. 0.44t.That is to say, state (product of will not cooking are placed on the state on the rotating disk 11) in the early stage, though the time interval of signal As1 and signal Bs1 is 0.28t, but in case when being placed on the cooking product of 7kg on the rotating disk 11, the time interval of signal As1 and signal Bs1 is 0.44t, and Hall element IC47 can take out different time signal at interval according to the weight of cooking product.Therefore, utilize the output of this Hall element IC47, but the weight of instrumentation cooking product.In addition, this addendum modification is converted into weight, is undertaken by microcomputer (diagram is omitted).

Figure 15 represents to be applied to the relative displacement with the 1st of load on the rotating disk (weight of cooking product) by percentage to detect with the Hall element IC output of the magnet B1 of member 42 sides and use the figure in the time interval that the Hall element IC of the magnet A1 of member 43 sides exports with respect to the 2nd relative displacement detection, be with each time interval t between magnet A1, A2, A3 be made as 100%, the percentage corresponding with this t.In addition, with the corresponding magnet B2 of magnet A2, also identical with the relation of the corresponding magnet B3 of magnet A3.Also learn from this Figure 15, load 0 occasion be 28% (0.28t), load the occasion of 1kg be about 30% (0.30t), load the occasion of 4kg be about this being directly proportional of 38% (0.38t) with load and the time interval elongated, under peak load (7kg), be about 44% (0.44t).

On the other hand, Figure 16 represents to be applied to the relative displacement with the 2nd of institute on the rotating disk weight of product (cooking) by percentage and detects with the Hall element IC output of the magnet A2 of member 43 sides and use the figure in the time interval that the Hall element IC of the magnet B1 of member 42 sides exports with respect to the 1st relative displacement detection, be with each time interval t between magnet A1, A2, A3 be made as 100%, the percentage corresponding with this t.In addition, with the corresponding magnet A3 of magnet B2, also identical with the relation of the corresponding magnet A1 of magnet B3.Also learn from this Figure 16, to be 72% (0.72t), load be about 70% (0.70t), load in the occasion of 1kg to load is about this being directly proportional with load of 62% (0.62t) and the time interval shortens in the occasion of 4kg in 0 occasion, under peak load (7kg), be about 56% (0.56t).

According to this relation, can detect the weight of cooking product, if know the weight of cooking product, just can automatically set the cooking time etc. after its consideration.

Yet in present explanation, the 2nd relative displacement detects with the relative displacement detection with the 1st of magnet of member 43 sides and is made of 3 couple of 3 respectively with the magnet of member 42 sides, but both can be set as manyly, also can be set as for example 1 pair.Say on the principle, only adopt 1 pair of magnet with the magnet of member 42 sides, also the addendum modification of rotating disk 11 can be taken out as the displacement in the time interval of Hall element IC47 even the 2nd relative displacement detects with the relative displacement detection with the 1st of magnet of member 43 sides.But, to irrespectively can use with 50KHz area and 60KHz regional disparity, preferably with as shown in Figure 14 time that becomes benchmark (this occasion be the 2nd relative displacement detection with the time interval t between the magnet of each magnet A1, A2 of member 43 sides, A3) accordingly addendum modification (=ratio) represent.Therefore, for obtaining addendum modification, the magnet total that the 1st and the 2nd relative displacement detects with member 42,43 preferably is set as at least 3.

As mentioned above, in above-mentioned example, the axial addendum modification of rotating disk 11 is transformed into the addendum modification that the 1st relative displacement detects the direction of rotation of using member 42, obtain the output that Hall element IC47 is directly proportional with the addendum modification of this direction of rotation, according to the addendum modification of the output of this Hall element IC47, just can detect the weight of the cooking product that are placed on the rotating disk 11.In addition, these weight detecting actions can be placed on the rotating disk 11, be undertaken by making in the rotation of cooking the rotating disk 11 that begins at the product of will cooking, and maximum can be carried out within rotating disk 11 rotations 1 circle, can carry out high efficiency weight detecting.

In addition, during rotating disk 11 rotations, the 1st and the 2nd relative displacement detects with member 42,43 and keeps circumferential position relation by force application spring 45, and utilizes sheet spring 50 by being pressed on the packing ring 54 that becomes datum level.Therefore, the position relation does not produce deviation during rotation, can produce correct addendum modification,, can carry out correct weight detecting that is.

In addition, be contained in structure in 1 housing 14 owing to make with being used for rotating rotating driving device 12 that drives rotating disk 11 and the weight detecting portion 13 that is used for sense weight, in other words, made pack into structure in the rotating driving device 12 with weight detecting portion 13, and behind assembly weight test section 13 and the rotating driving device 12 both are combined respectively, therefore, in the time of can reducing the assembler, make integral miniaturization, also can reduce cost.

In addition, aforesaid example is the example of the preferable example of the present invention, but is not limited thereto, and without departing from the spirit and scope of the present invention, can do various distortion and implement.For example, in aforesaid example, rotating disk 11 only is set as to rotate to a direction illustrates, but also rotating disk 11 can be set as and can two-wayly rotate.In this occasion, among the present invention, force application spring 45 as position holding device detects the structure of carrying out circumferential position maintenance with member 42,43 owing to becoming to the 1st and the 2nd relative displacement as described above, so can not bring error to measured value, only the certain value of direction of rotation is just revised and can be tackled, thereby can further bring into play effect as checkout gear.

In addition, in aforesaid example, utilize the magnetic detection device of magnet A1, A2, A3, B1, B2, B3 and Hall element IC47 to detect addendum modification, but utilize other device also can realize.For example, also can detect with the relative displacement of member 42 and detect two sides that use member 43, several slits to mutual coincidence are set, to variation of axial position, make the length variations of the slit of coincidence by thrust shaft in the 1st relative displacement with the 2nd.

Under the situation of this structure, clip slit and the photo-electric conversion device of subtend configuration photodiode and phototransistor etc., to variation of axial position, the slot length of the slit of coincidence is changed by thrust shaft.And, the slot length of the slit that overlaps is changed as taking out from the interval of the output signal of phototriode, can carry out weight detecting in view of the above.Thus, but with aforesaid example sense weight in the same manner.

In addition, in aforesaid example, be to utilize the axial displacement of thrust shaft 41 and make the 1st to detect relative to displacement and to rotate displacement with member 42, the 2nd relative displacement detects and does not produce displacement with member 43, but also can make 42,43 displacements together of two members, or the 2nd relative displacement is detected with member 43 displacements.In addition, magnet also can adopt the circular outer peripheral portion with rubber magnet to be set as other the shape and the structure such as structure of convex.In addition, also helical spring 46 can not be set as " square wire rod helical spring ", also can be set as helical spring circular or other shape.In addition, also can not be set as helical spring but be set as flat spring or other spring such as disk spring, also can be set as other elastic component such as elastomeric material or plastic material.

In addition, also force application spring 45 can not be set as helical spring and be set as rubber or other elastic component.The 50b of spring portion of sheet spring 50 can be set as 10 and be set as 3 120 ° of arranged spaced yet, or be set as 6 60 ° of arranged spaced.In addition, also can not be set as sheet spring 50 and be set as other force application apparatus such as disk spring, rubber component.

In addition, in aforesaid example, be that example is illustrated with the occasion that detects the weight of cooking product in the micro-wave oven, and the invention is not restricted to micro-wave oven, also applicable to the weight detecting of other devices such as baking oven and toaster.In addition, the present invention is also applicable to the detection of cooking product other Item Weight in addition.

As above explanation, in the Weight detecting device of the present application, because thrust shaft is set to be detected with member and the 2nd relative displacement detection member that rotates by the rotary driving force that is subjected to from drive source to the 1st relative displacement of rotating according to variation of axial position of variation of axial position according to the weight that should detect, export as the weight detecting signal with respect to the signal that the 2nd relative displacement detects the relative addendum modification of using member detecting with member according to the 1st relative displacement, so carry out high-precision weight detecting by simple structure, compare with the Weight detecting device of traditional electrostatic capacitive, can obtain miniaturization.In addition, because detecting with member, the 1st and the 2nd relative displacement keeps circumferential position relation, so also can correctly carry out weight detecting in the rotation by position holding device.

In addition, in another the Weight detecting device that becomes the present application, because the 1st and the 2nd relative displacement detection is set as by force application apparatus it to axial force distribution and by the structure that is pressed in datum level with member, therefore, numerical value when not applying the A-stage of weight has reliability, can carry out correct weight detecting.

Claims (8)

1. Weight detecting device is characterized in that having:

According to the weight that should detect and to the thrust shaft of variation of axial position;

At least 1 revolving member that combines with this thrust shaft and be provided with;

Addendum modification according to thrust shaft makes this revolving member rotate the rotation displacement device of ormal weight;

Under the displacement state, make the whirligig of described revolving member to its rotation direction rotation;

At the detector detectable region configuration that is arranged at the detected body on the described revolving member, that this detected body is detected,

Setting utilizes the rotation of described revolving member by this detector and is scaled the weight scaler of weight when the addendum modification of the revolving member that is subjected to the displacement of described rotation displacement device detected, with this addendum modification.

2. Weight detecting device is characterized in that having:

According to the weight that should detect and to the thrust shaft of variation of axial position;

Detect with the 1st relative displacement coaxial setting of this thrust shaft, that rotate according to the axial displacement of this thrust and to use member;

Relative displacement with the 1st detect with member in couples with the 2nd relative displacement detection member coaxial setting of described thrust shaft, that rotate by the rotary driving force that is subjected to from drive source;

Make the described the 1st and the 2nd relative to displacement detect with member and described thrust shaft in conjunction with, when described thrust shaft make at least according to the addendum modification of thrust shaft during to variation of axial position the described the 1st relatively displacement to detect with member be that the center is only rotated the regulation rotational angle, its revolving force can be passed to the displacement direction-changing device that member and described thrust shaft are used in the described the 1st relative displacement detection when the described the 2nd relative displacement detection is subjected to rotating from described drive source drives power with member with the thrust shaft;

To detect with member according to the described the 1st relative displacement and detect the weight detecting signal output apparatus of the signal of the relative addendum modification of using member as the output of weight detecting signal with respect to the described the 2nd relative displacement.

3. Weight detecting device as claimed in claim 2, it is characterized in that, described weight detecting signal output apparatus is to use the magnetic detection device of magnet and Hall element, described magnet is located at the described the 1st relative displacement respectively and detects with the relative displacement detection with the 2nd of member with on the member, described Hall element fixed configurations can detect the described the 1st relative displacement on the position of detecting with the magnetic force separately that magnet sent of member side with the magnet of member side and the 2nd relative displacement detection, the described the 1st relative displacement from relatively this Hall element rotation detected with the relative displacement detection with the 2nd of magnet of the member side magnetic force with the magnet of member side detect, and will detect the signal output that detects the time interval of the relative addendum modification of using member side with member with respect to the 2nd relative displacement, and it is exported as the weight detecting signal according to the described the 1st relative displacement.

4. Weight detecting device is characterized in that having: according to the weight that should detect and to the thrust shaft of variation of axial position; The the 1st and the 2nd relative displacement that is provided with this thrust shaft combination detects uses member; Addendum modification according to described thrust shaft makes described 2 rotation displacement devices that relatively rotate the displacement ormal weight relative to the displacement detection with member; Make the described the 1st and the 2nd relative displacement detect the position holding device that is kept usefulness with member in the position of direction of rotation relation; Make the described the 1st and the 2nd relative displacement detect the rotating driving device that rotates with described thrust shaft with member; Detect with the detector detectable region configuration of the detected body on the member, that this detected body is detected being arranged at the described the 1st and the 2nd relative displacement respectively, and be provided with by this detector, utilize the described the 1st and the 2nd relatively displacement detect with the one rotation of member when detected with the relative addendum modification of member by described the described the 1st and the 2nd relative displacement detection of rotating the displacement device displacement and being subjected to described position holding device maintenance, this addendum modification is scaled the weight scaler of weight.

5. Weight detecting device as claimed in claim 4 is characterized in that, described position holding device detects with member between the two, both give peripheral force to this force application spring and constitutes by being located at the described the 1st and the 2nd relative displacement.

6. Weight detecting device is characterized in that having: according to the weight that should detect and to the thrust shaft of variation of axial position; The the 1st and the 2nd relative displacement that is provided with this thrust shaft combination detects uses member; Addendum modification according to described thrust shaft makes described 2 rotation displacement devices that relatively rotate the displacement ormal weight relative to the displacement detection with member; To axially the described the 1st and the 2nd relative displacement being detected the force application apparatus of using the member application of force; The the 1st and the 2nd relative displacement that is subjected to this force application apparatus application of force is detected the datum level that the end face with member is supported; Make the described the 1st and the 2nd relative displacement detect the rotating driving device that rotates with member and described thrust shaft one; Detect with the detector detectable region configuration of the detected body on the member, that this detected body is detected being arranged at the described the 1st and the 2nd relative displacement respectively, and be provided with by this detector, utilize the described the 1st and the 2nd relatively displacement detect with the one of member and rotate and when detected with the relative addendum modification of member by described the described the 1st and the 2nd relative displacement detection of rotating the displacement device displacement, with this addendum modification, be scaled the weight scaler of weight.

7. Weight detecting device as claimed in claim 6, it is characterized in that, described force application apparatus, constitute with the tabular spring member between the member by the relative displacement detection of a side top board inner face that is configured in the metal system housing that covers described Weight detecting device with the described the 1st and the 2nd, described datum level constitutes with the plain washer between the member by being configured in to detect with the opposite side top board inner face of the opposed described housing of a described side top board or this inner face and the described the 1st and the 2nd relative displacement.

8. micro-wave oven, can make this rotating disk in the micro-wave oven of variation of axial position and the Weight detecting device that the weight that is applied on the rotating disk detected according to this addendum modification having according to being applied to the weight on the rotating disk, it is characterized in that described Weight detecting device is as claim 1 or 4 described Weight detecting devices.

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