CN101074735B

CN101074735B - Electromotor safety valve

Info

Publication number: CN101074735B
Application number: CN2007101040129A
Authority: CN
Inventors: 和田则夫; 清水正则; 水谷圭一
Original assignee: Rinnai Corp
Current assignee: Rinnai Corp
Priority date: 2006-05-19
Filing date: 2007-04-30
Publication date: 2010-09-15
Anticipated expiration: 2027-04-30
Also published as: KR20070111966A; CN101074735A; TW200743754A; JP2007309437A; KR100812801B1

Abstract

An electromotor safety valve whose annular variant part (61) surrounds the central part (62) which contacts with the low end of the rod (51), if press down the movable iron piece when the spool (6) is closed, the central part (62) can move downward and restrict the load acting on the step motor (2). The invention can prevent the emergence of noise and miniaturize the step motor (2) to reduce the cost.

Description

Electromotor safety valve

Technical field

The present invention relates to will utilize stepping motor carry out before and after on the movable iron that but motor magnet presses against with spool is connected of action and open the electromotor safety valve of valve but motor magnet being adsorbed under the state on the movable iron spool mentioned.

Background technique

As this electromotor safety valve in the past, known have a kind of electromotor safety valve that has stepping motor, the outside thread member is connected and has the retainer that screws togather with this outside thread member with the running shaft of this stepping motor.Because this retainer is by spline, thus when the positive and negative rotation of the running shaft of stepping motor, the motion that is in line of the rotation transformation of running shaft, retainer direction forwards, backwards moves.

But motor magnet is installed on the retainer, and bar-shaped bar is engaged with the spool of the rubber system that opens and closes valve port, and forms movable iron in the end of bar.But this movable iron is relative with motor magnet.

Spool be subjected to spring to the application of force of closing the valve direction, usually, valve port is closed by spool because of the application of force of spring.When valve port is opened, but motor magnet is moved to movable iron, but movable iron is adsorbed on the motor magnet.But the time not only make the magnetic pole and the movable iron butt of motor magnet in absorption, but and in order to adsorb reliably with the magnetic pole of motor magnet by being pressed on the movable iron.

So, but when being adsorbed on movable iron on the motor magnet, thereby but make the stepping motor counter-rotating that motor magnet is retreated.Owing to but movable iron is adsorbed on the motor magnet, so movable iron makes spool leave valve port by bar and valve port is opened.When gas burner is flame-out etc., but by stopping to the motor magnet energising, but movable iron just be not adsorbed on the motor magnet, spool is moved into the valve state that closes (for example with reference to patent documentation 1) because of the application of force of spring.

Patent documentation 1: TOHKEMY 2005-30440 communique (Fig. 1)

In above-mentioned existing electromotor safety valve, but when making movable iron be adsorbed on the motor magnet, owing to further movable iron is pushed to closing the valve direction from the valve state that closes of spool, so acting on bigger load on the stepping motor.Especially, accumulated the machining tolerance and the build-up tolerance of each part, but, just acted on bigger load on the stepping motor in the short occasion of the distance of motor magnet and movable iron.

In case the bigger load of effect can not rotate even stepping motor is transfused to driving pulse yet on the stepping motor, produces the phenomenon of so-called stall.If produce this stall, can produce the not well noise in the cycle identical with driving pulse.Therefore, can damage the unfavorable condition of the Gas appliance commodity of the electromotor safety valve of packing into.In addition, when producing stall,,, make the unfavorable condition of dryelement cell life-span decline in addition so be the occasion of power supply with the dryelement cell because the power consumption of stepping motor increases in the stall.If do stepping motor to such an extent that maximize, increase the output torque, can prevent stall, stepping motor is maximized though members such as spool produce resiliently deformable, can produce new unfavorable conditions such as cost rises, the restriction of installing space, the dryelement cell lost of lifeization, be undesirable.

Summary of the invention

Therefore, in view of the above problems, the object of the present invention is to provide a kind of stepping motor the maximization just can prevent the electromotor safety valve of the generation of the noise that stall causes.

For achieving the above object, electromotor safety valve of the present invention has stepping motor, with the motion that is in line of the rotation transformation of this stepping motor, but motor magnet constitutes forwards, backwards and moves freely, and spool with rubber system of the application of force that is subjected to the close port direction, but the end in the motor magnet side of the bar that engages with this spool forms movable iron, but described motor magnet is advanced and but movable iron is adsorbed on the motor magnet with the movable iron butt, absorption movable iron state under by but motor magnet is retreated, making spool leave valve port opens valve port, it is characterized in that, when but spool closes under the valve state described motor magnet and movable iron butt, the load limit that acts on the stepping motor is folded between stepping motor and the described spool in the load limit mechanism below the specified value.

But when motor magnet absorption movable iron, but under the state of the magnetic pole of motor magnet and movable iron butt, but if again motor magnet is moved to closing the valve direction, because spool is in and closes the valve state, so movable iron can not further be moved to closing displaceable valve again.Therefore, but the magnetic pole of motor magnet by being pressed on the movable iron, the stress when this is pushed plays reaction as load to stepping motor.And this load is if stepping motor is with regard to stall when surpassing specified value.Therefore, by above-mentioned load limit mechanism is set, just can with the load limit that acts on stepping motor below specified value, prevent stall.

As this load limit mechanism, for example also can: when spool closes valve, if the spool side end of bar pushes spool to closing the valve direction, then by with the part of the spool of the end butt of this bar to closing the distortion of valve direction, thereby allow bar to move, constitute described load limit mechanism with this to closing the valve direction.

Perhaps, also can constitute: in the end of the spool side of described bar, will with respect to spool elastic promptly be folded in freely and spool between resilient member be made as described load limit mechanism, the contraction by resilient member when spool closes valve allows bar to closing moving of valve direction.

In this occasion, can think that for example when with spring etc. during as resilient member, resilient member contacts with spool with narrow and small area sometimes.When spool is formed by soft material such as rubber, resilient member can nip spool or spool local deformation.When producing this unfavorable condition, between described resilient member and spool, preferably folder is established the pressing member of dispersion to the application of force of the resilient member of spool effect.

In addition, also can: be provided with and utilize described stepping motor and the screw member that rotates screws togather and the retainer that moves of direction forwards, backwards, simultaneously but motor magnet is mounted to respect to this retainer forwards, backwards direction move freely, but and between retainer and motor magnet, motor magnet is constituted described load limit mechanism to the resilient member of the movable iron side application of force but establish by folder.

As seen from the above description, the present invention can prevent the stall of stepping motor by above-mentioned load limit mechanism is set, stepping motor is maximized, therefore, the degrees of freedom of the mounting point of electromotor safety valve increases, and can prevent that the cost of electromotor safety valve from rising.

Description of drawings

Fig. 1 is the diagrammatic sketch of an expression example structure of the present invention.

Fig. 2 is illustrated in the diagrammatic sketch that is provided with the example of load limit mechanism on the part shown in the A.

Fig. 3 is illustrated in the diagrammatic sketch that is provided with the example of other load limit mechanism on the part shown in the A.

Fig. 4 is illustrated in the diagrammatic sketch that is provided with the example of load limit mechanism on the part shown in the B.

Embodiment

With reference to Fig. 1, the 1st, an example of electromotor safety valve of the present invention.On the shell 11 of this electromotor safety valve, be provided with the inflow entrance 12 of inflow gas and the valve port 13 of eluting gas.On the top of shell 11 stepping motor 2 is installed.This stepping motor 2 is rotated with the angle of swing that the umber of pulse with the driving pulse of importing is directly proportional, and can positive and negative rotation switch freely.

On the running shaft of this stepping motor 2, be provided with outside thread 21.On the other hand, the 3rd, but motor magnet is maintained on the retainer 31 that screws togather with outside thread 21.This retainer 31 is inserted in rotation prevention portion 14 free to advance or retreatly.In addition, the block function that retainer 31 moves towards the top is played in the lower end of rotation prevention portion 14.But motor magnet 3 is surrounded by the housing 32 that is fixed on the retainer 31.

But dispose the movable iron 5 relative with the below of motor magnet 3.This movable iron 5 is formed on the upper end of columned bar 51, and the spool 6 of rubber system is installed in the lower end of bar 51.And hookup wire coil spring 4 between spool 6 and housing 32.Therefore, spool 6 be subjected to all the time coil spring 4 to closing the i.e. application of force of below of valve direction, under illustrated state, be subjected to the application of force of coil spring 4 and be crimped on the periphery of valve port 13.Therefore, valve port 13 is closed.

But but state representation motor magnet 3 shown in Figure 1 is in the rising end position of the above-below direction moving range of motor magnet 3.When valve port 13 is closed, but make stepping motor 2 actions from position shown in Figure 1 and motor magnet 3 is descended.

Like this, but though motor magnet 3 and movable iron 5 butts, but in order reliably but movable iron 5 to be adsorbed on the motor magnet 3, but further stepping motor 2 being driven further moves motor magnet 3 to closing the valve direction, but, when periphery butt, the movable iron 5 of spool 6 and valve port 13 be can not be further when closing the state that the valve direction moves, might bigger load act on the stepping motor 2 and produce stall.

Therefore, as shown in Figure 2, variant part 61 by ring-type surrounds the middle body 62 that contacts with the underpart 52 of bar 51, in movable iron 5 to closing the valve direction when pressing down, middle body 62 moves like that downwards shown in Fig. 2 (b) from the state shown in Fig. 2 (a), does not act on the load more than the specified value on stepping motor 2.

Load limit mechanism also can be the structure beyond shown in Figure 2, for example as shown in Figure 3, also push strut 7 can be mounted to free to advance or retreatly, by 71 pairs of these push strut 7 of spring application of force downwards, makes its underpart 52 from bar 51 further outstanding downwards.

When making structure like this, if when spool 6 closes valve, further push the occasion of movable iron 5 downwards, push strut 7 enters shown in (b) in the bar 51 like that from the state of figure (a), and spring 71 compression just can will act on load limit on the stepping motor 2 below specified value.

In example shown in Figure 3, enlarge end 72 areas of push strut 7 so that act on the application of force dispersion of the spring 71 on the spool 6, when preventing spool 6 local deformations, can push spool 6 reliably, but also can not use directly pushing spool 6 of push strut 7 usefulness springs 71 according to the material of spool 6.In addition, also push strut 7 or the member that is equivalent to it can be fixed on spool 6 sides integratedly.

Yet, in above-mentioned Fig. 2 and structure shown in Figure 3, be the structure that load limit mechanism is set on the A of Fig. 1 part, but also can on the B part, load limit mechanism be set.

For example, as shown in Figure 4, but compression is provided with spring 33 between retainer 31 and motor magnet 3, but when make motor magnet 3 from the position of movable iron 5 butts further to closing the valve direction when moving, spring 33 is compressed, but also restriction in the load of stepping motor 2.

The present invention is not limited to above-mentioned form, also can implement various changes without departing from the spirit and scope of the present invention.

Claims

1. electromotor safety valve, has stepping motor, with the motion that is in line of the rotation transformation of this stepping motor, but motor magnet is constituted forwards, backwards to be moved freely, and spool with rubber system of the application of force that is subjected to the close port direction, but the end in the motor magnet side of the bar that engages with this spool forms movable iron, but described motor magnet is advanced and but movable iron is adsorbed on the motor magnet with the movable iron butt, absorption movable iron state under by but motor magnet is retreated, make spool leave valve port and valve port is opened, it is characterized in that, load limit mechanism is folded between stepping motor and the described spool, with at spool for closing under the valve state, but when described motor magnet and movable iron butt, but the state even stepping motor further drives from this butt makes motor magnet to the movable iron side shifting, also can will act on load limit on the stepping motor by the resiliently deformable of described load limit mechanism below specified value.

2. electromotor safety valve as claimed in claim 1, it is characterized in that, when spool closes valve, if the spool side end of bar pushes spool to closing the valve direction, then with the part of the spool of the end butt of this bar to closing the distortion of valve direction, allow bar to move, constitute described load limit mechanism with this to closing the valve direction.

3. electromotor safety valve as claimed in claim 1, it is characterized in that, end in the spool side of described bar, will be with respect to spool freely elastic and be folded in the end of spool side of described bar and the resilient member between the spool and be made as described load limit mechanism, the contraction by resilient member when spool closes valve allows bar to closing moving of valve direction.

4. electromotor safety valve as claimed in claim 3 is characterized in that, between described resilient member and spool, folder is if the pressing member that the application of force of the resilient member of spool effect is disperseed.

5. electromotor safety valve as claimed in claim 1, it is characterized in that, be provided with that the screw member that rotates with utilizing described stepping motor screws togather and the retainer that moves of direction forwards, backwards, simultaneously but motor magnet is mounted to respect to this retainer forwards, backwards direction move freely, but and between retainer and motor magnet, motor magnet is constituted described load limit mechanism to the resilient member of the movable iron side application of force but establish by folder.