CN110233540A - A kind of driving mechanism and electrically driven curtain - Google Patents

Abstract

The present invention relates to driving mechanism technical fields, and in particular to a kind of driving mechanism and electrically driven curtain.The driving mechanism includes motor and clutch, and the motor includes the hollow shaft with open end；The clutch includes movable axis and function part, the movable axis protrudes into the hollow shaft from the open end, and matched with the function part, for the movable axis for driving component to be driven, the function part is relatively fixed or relatively rotate for making the movable axis and the hollow shaft.Even if driving mechanism provided by the present invention is in the power-off state, the movable axis that can also make it internal by function part is rotated relative to hollow shaft, to prevent in the power-off state, can not be adjusted and the position of the component to be driven of driving mechanism cooperation or posture.

Description

A kind of driving mechanism and electrically driven curtain

Technical field

The present invention relates to driving mechanism technical fields, and in particular to a kind of driving mechanism and electrically driven curtain.

Background technique

With the development of science and technology, miscellaneous automation equipment is invented and is applied, so that people's lives are increasingly It is convenient.For example, electrically driven curtain and electric clothes hanger etc., but power blackout situation once occurs for current electrically driven curtain, motor cannot Rotation, and it is unable to complete the work for opening and closing curtain, this brings inconvenience to people's lives.

Summary of the invention

(1) the technical problem to be solved by the present invention is current driving mechanism can not rotate in the event of a power failure, into And it may make troubles in some cases to the production and living of people.

(2) technical solution

In order to realize above-mentioned technical problem, the present invention provides a kind of driving mechanisms comprising motor, the motor include Hollow shaft with open end；

Clutch, the clutch include movable axis and function part, and the movable axis protrudes into the sky from the open end It in mandrel, and is matched with the function part, for the movable axis for driving component to be driven, the function part is described for making Movable axis and the hollow shaft it is relatively fixed or relatively rotate.

Optionally, the function part includes electromagnet and magnetic portion, and the electromagnet and the hollow shaft are relatively fixed, institute Magnetic portion and the activity axis connection are stated,

In the state that the electromagnet and the magnetic portion are mutually attracted, the movable axis is arranged to and the hollow shaft It is relatively fixed；

In the state that the electromagnet and the magnetic portion are separated from each other, the movable axis is arranged to and the hollow shaft It relatively rotates.

Optionally, the function part includes electromagnet and iron block, and the electromagnet and the hollow shaft are relatively fixed, described The axial direction of movable axis is identical as gravity direction, and the iron block is located at the lower section of the electromagnet, and with the activity axis connection,

In the state that the electromagnet and the iron block are attracted, the movable axis is arranged to opposite with the hollow shaft solid It is fixed；

In the state that the electromagnet is separated with the iron block, the movable axis is arranged to turn opposite with the hollow shaft It is dynamic.

Optionally, be provided with the first position limiting structure on the movable axis, have in the hollow shaft the second position limiting structure and Be rotatably assorted structure, in the rotation direction of the hollow shaft, first position limiting structure and second position limiting structure limit Cooperation or first position limiting structure and the structure movement cooperation that is rotatably assorted.

Optionally, first position limiting structure is the axially extending keyway along the movable axis, and the keyway is with respect to institute The outer surface depressions of movable axis are stated, and at least one end of the keyway in the axially opposing both ends has opening；

The inner surface that structure is the hollow shaft that is rotatably assorted, second position limiting structure is positive stop key, the limit The relatively described structure protrusion that is rotatably assorted of position key, and the positive stop key and the keyway are in the rotation direction upper limit of the hollow shaft Position cooperation.

Optionally, the keyway is provided with holding section, the holding section and the positive stop key away from one end of the opening Axial limiting along the hollow shaft cooperates.

Optionally, the keyway and the positive stop key are provided with multiple, and multiple positive stop keys are along the hollow shaft The setting of rotation direction interval, multiple keyways and multiple positive stop keys correspond cooperation.

Optionally, in the axial direction of the hollow shaft, the maximum length of the positive stop key is less than the movable axis with respect to institute State the maximal translation distance of hollow shaft.

Optionally, driving mechanism provided by the present invention further includes retarder, and the retarder and the motor drive connect It connects.

Based on any of the above-described provided driving mechanism, the present invention also provides a kind of electrically driven curtains comprising curtain axis with Any of the above-described driving mechanism, the driving mechanism and the curtain axis are sequentially connected.

(3) beneficial effect

The present invention provides a kind of driving mechanism comprising motor and clutch, in the movable axis and motor in clutch Hollow axis connection, and movable axis is also used to that curtain axis is driven to wait driving part；Meanwhile setting in the clutch of the driving mechanism Functional portion, movable axis are matched with function part, to make movable axis form phase in varied situations with hollow shaft by function part To connection relationship that is fixed or relatively rotating；In detail, in the energized state, function part generate corresponding actions, hollow shaft with Movable axis is relatively fixed, hollow shaft rotation, and drives the movable axis rotation being attached thereto, so that curtain axis be driven to wait driving portion The work for opening or closing curtain is completed in part rotation；And in the event of a power failure, by function part can also make movable axis with it is hollow Axis is separated from each other, and then makes to relatively rotate between component to be driven and hollow shaft, to make the rotation of component to be driven no longer It is limited by magnetic resistance of motor effect, in this case, user can make curtain axis wait driving part by manually mode Rotation, to complete the operation of opening and closing curtain.

Detailed description of the invention

The advantages of above-mentioned and/or additional aspect of the invention, will be apparent from the description of the embodiment in conjunction with the following figures Be readily appreciated that, in which:

Fig. 1 is the structural schematic diagram of driving mechanism provided by the embodiment of the present invention；

Fig. 2 is the schematic diagram of internal structure in driving mechanism provided by the embodiment of the present invention；

Fig. 3 is the sectional view of part-structure in driving mechanism provided by the embodiment of the present invention；

Fig. 4 is a kind of installation diagram of movable axis and stop collar in driving mechanism provided by the embodiment of the present invention.

Appended drawing reference

1- motor；

11- hollow shaft；

111- stop collar；

112- axis body；

113- positive stop key；

2- clutch；

21- movable axis；

211- keyway；

212- opening；

The holding section 213-；

22- function part；

221- electromagnet；

222- iron block；

3- retarder；

4- shell；

5- drive shaft；

6- shaft coupling.

Specific embodiment

To better understand the objects, features and advantages of the present invention, with reference to the accompanying drawing and specific real Applying mode, the present invention is further described in detail.It should be noted that in the absence of conflict, implementation of the invention Feature in example and embodiment can be combined with each other.

As shown in Figure 1, the present invention provides a kind of driving mechanism comprising motor 1 and clutch 2, wherein motor 1 can be Curtain axis is driven to wait the rotation of driving part (not shown) under the action of electric power, clutch 2 is able to achieve connection and separation electricity The purpose of machine 1 and component to be driven.Motor 1 include hollow shaft 11, hollow shaft 11 be motor 1 drive shaft, hollow shaft 11 with from Clutch 2 connects, to drive component to be driven by motor 1, promote the degree of automation in the case where energization；Exist in order to prevent In the case where power-off, because motor 1 magnetoresistance caused by hollow shaft 11 and component to be driven it is locked, driving provided by the present invention Hollow shaft 11 in the motor 1 of mechanism is provided with open end, so that the movable axis 21 of clutch 2 is stretched to by aforementioned open end It, can be in the corresponding of function part 22 by matching movable axis 21 with the function part 22 in clutch 2 in the cavity of hollow shaft 11 Under movement, according to the difference of on-off electric condition, make to be formed between movable axis 21 and hollow shaft 11 relatively fixed or relative rotation Relationship, to prevent under power blackout situation, because of the magnetoresistance of motor 1, even if causing component to be driven in the work of other external force Self-position can not be moved or changed under.

In detail, in the case where energization, movable axis 21 and hollow shaft 11 can be made to be formed by function part 22 and fixed Connection relationship, and then make motor 1 under command adapted thereto, drive component to be driven to reach setting position, and treat driving part Position is locked, and is prevented component autonomous action to be driven or is acted by other external force；In the event of a power failure, by function part 22 are separated from each other movable axis 21 with hollow shaft 11, to make the item for having relative rotation between component to be driven and hollow shaft 11 Part, even if component to be driven also can be relatively hollow under power the manual actuation of user the effects of so that motor 1 is there are magnetoresistance 11 activity of axis.

Specifically, the design parameters such as the model of motor 1 and power can be selected according to the actual situation, be not construed as limiting herein, The size of movable axis 21 can wait the size of driving part and specification corresponding selected according to curtain axis；Movable axis 21 with it is to be driven It can be connected by such as driving members such as gear mechanism, chain-drive mechanism or tape handler between component；Preferably, such as Fig. 2 institute Show, driving mechanism provided by the present invention is also provided with individual drive shaft 5, can between the drive shaft 5 and movable axis 21 To be sequentially connected by one or more shaft couplings 6, in this case, component to be driven then can be passed directly with drive shaft 5 Dynamic connection, to promote the ease of use of the driving mechanism.Correspondingly, the size of hollow shaft 11 can be with the ruler of movable axis 21 Very little phase is suitable, so that movable axis 21 be enable to stretch in hollow shaft 11 by the open end of hollow shaft 11, and is formed with hollow shaft 11 Relatively fixed or relative rotation relationship.There are many specific structure and working principle of function part 22 are equal, as it can be manual lock Buckle structure, to realize the purpose for connecting or separating hollow shaft 11 and movable axis 21 by mechanical mechanism, and in the driving mechanism The course of work in, user can by change function part 22 position or internal structure realization connect or separate 11 He of hollow shaft The purpose of movable axis 21, it is clear that there are many kinds of the common parts for having this function, no longer introduces one by one herein；Alternatively, function Portion 22 can also be auto-fastening structure, to realize locked and opening movable axis 21 and sky by external force such as electric power or elastic forces The purpose of mandrel 11；For another example, function part 22 can also be connected by way of electric magnetisation by magnetive attraction using electromagnetic principle Movable axis 21 and hollow shaft 11 are connect or separated, considers that text is succinct, is no longer discussed in detail herein.

The present invention provides a kind of driving mechanism comprising motor 1 and clutch 2, movable axis 21 and motor in clutch 2 Hollow shaft 11 in 1 connects, and movable axis 21 also waits driving part to connect with curtain axis；Meanwhile the clutch of the driving mechanism Function part 22 is provided in device 2, movable axis 21 is matched with function part 22, with by function part 22, make movable axis 21 with it is hollow Axis 11 forms connection relationship that is relatively fixed or relatively rotating in varied situations；In detail, in the energized state, function part 22 generate corresponding actions, and hollow shaft 11 and movable axis 21 are relatively fixed, and hollow shaft 11 rotates, and drive the movable axis being attached thereto 21 rotations complete the work for opening and closing curtain so that curtain axis be driven to wait driving part rotation；And the case where powering off Under, movable axis 21 can also be made to be separated from each other with hollow shaft 11 by function part 22, and then make component to be driven and hollow shaft 11 it Between can relatively rotate, so that the rotation of component to be driven be made no longer to be limited by magnetic resistance of motor effect, in this case, user Curtain axis can be made to wait driving part rotation by manually mode, to complete the operation of opening and closing curtain.

Optionally, function part 22 may include electromagnet and magnetic portion, and electromagnet can be made to be equipped with individual power supply Component, such as battery, magnetic portion can be electromagnet, or permanent magnet.It, can in the assembling process of the driving mechanism To be passed through the electric current of direction initialization to electromagnet according to the direction of two magnetic poles in magnetic portion so that electromagnet and magnetic portion it Between generate the active force to attract each other, so that movable axis and hollow shaft is formed fixed relation, to drive in motor work Movable axis moves together, to drive component to be driven to rotate；Correspondingly, in the case where motor powers off, it can control aforementioned confession Electrical components input reverse current into the coil of electromagnetic part, so that electromagnet and magnetic portion is generated mutually exclusive power, make magnetic portion Drive movable axis far from electromagnet, and then be separated from each other movable axis with hollow shaft, in this case, component to be driven and sky Mandrel also can be relatively movable, so that under the effect of external force, component to be driven can change self-position.

Specifically, the parameters such as magnet spool circle number and the size of current for being passed through coil can according to the actual situation really Fixed, maximum distance between magnetic portion and electromagnet can also be practical according to greatest attraction forces between electromagnet and magnetic portion etc. Situation determines, to guarantee that movable axis and hollow shaft can relatively rotate, and electromagnet can be attracted under power on condition with magnetic portion；Magnetic Property portion can be iron-cobalt-nickel magnet, shape and size are not construed as limiting herein.Function part 22 using the above structure when, clutch Towards unrestricted, this can make the application scenarios diversification of the driving mechanism, liberalization, and this knot for installation site and installation The course of work of the function part 22 of structure is securely and reliably, flexible and changeable hardly by the interference of external condition.

Alternatively, as shown in figure 4, function part 22 can also include electromagnet 221 and iron block 222, wherein electromagnet 221 with The relationship that can be formed a fixed connection by connector between hollow shaft 11 can make activity during assembling driving mechanism The axial direction of axis 21 is identical as gravity direction, and so that iron block 222 is mounted on the lower section of electromagnet 221, and iron block 222 is connected to work It, can be in electromagnet 221 and 222 phase of iron block by setting movable axis 21 and corresponding structure in hollow shaft 11 on moving axis 21 In the state of being mutually attracted, movable axis 21 and hollow shaft 11 is set to form relatively-stationary connection relationship, correspondingly, in electromagnet In the state that 221 are separated from each other with iron block 222, movable axis 21 and hollow shaft 11 is made to form the connection relationship relatively rotated.

In detail, motor 1 and electromagnet 221 can share external power supply, thus under conditions of motor 1 is powered, It also alives in the coil of electromagnet 221, generates magnetive attraction, attract iron block 222 close to electromagnet 221, iron block 222, which drives, lives Moving axis 21 moves, and movable axis 21 and hollow shaft 11 is made to form relatively-stationary connection relationship, and in this state, motor 1 works, By the transmission effect of clutch 2, component to be driven is driven to rotate；On the contrary, in the case where motor 1 powers off, electromagnet 221 Power-off, iron block 222 fall under the collective effect of the gravity of itself and movable axis 21, divide movable axis 21 and hollow shaft 11 mutually From, and then enable movable axis 21 relative to the relative rotation of hollow shaft 11 or movement, correspondingly, with the relative rotation of hollow shaft 11 wait drive Dynamic component can also rotate under the action of other external force and movement.

It should be noted that the specific structure and function of function part 22 can change according to its own structure composition is corresponding, It has the function of making hollow shaft 11 and movable axis 21 change connection relationship at different conditions, certainly, in the driving mechanism Hollow shaft 11 and movable axis 21 can be made in the relative position difference of the two, changed empty by increasing other mechanisms or component Connection relationship between mandrel 11 and movable axis 21.

For example, the first position limiting structure can be set on movable axis 21, the second limit knot can be set in hollow shaft 11 It structure and is rotatably assorted structure, along the rotation direction of hollow shaft 11, the first position limiting structure and the second position limiting structure limit cooperation or the One position limiting structure and the structure movement cooperation that is rotatably assorted.In the course of work of driving mechanism, by changing movable axis 21 and sky The relative position of mandrel 11 can make to form relatively fixed or relative rotation relationship between movable axis 21 and hollow shaft 11.In addition, The two forms mode that is relatively fixed or relatively rotating relationship, and there are also other kinds, magnetic attracting modes as described above or manual The mode etc. of locking.

Specifically, the specific structure of the first position limiting structure, the second position limiting structure and the structure three that is rotatably assorted can have more Kind, for example, one can be protrusion in the first position limiting structure and the second position limiting structure, another one can be recess, and by setting Both fixed setting position can make movable axis 21 and hollow shaft 11 form limit cooperation in the rotation direction of hollow shaft 11 and close System；Correspondingly, according to the concrete form of the first position limiting structure, the specific structure for the structure that is rotatably assorted can be accordingly designed, thus By changing the relative position of hollow shaft 11 and movable axis 21, match the first position limiting structure with the structure that is rotatably assorted, in turn Make to relatively rotate between movable axis 21 and hollow shaft 11.

For example, the first position limiting structure can be strip bulge shape structure, the second position limiting structure can be strip groove, rotation Fit structure can be annular recess, and the structure that is rotatably assorted is connected with the second position limiting structure, and make to be rotatably assorted structure and the Axial direction distribution of two position limiting structures along hollow shaft 11.In this case, when movable axis 21 stretches in hollow shaft 11, first Position limiting structure is inserted into the second position limiting structure, can make movable axis 21 and hollow shaft 11 shape in the rotation direction of hollow shaft 11 At limit matching relationship；And after movable axis 21 translated up a distance along the axis of hollow shaft 11, the first position limiting structure from Abjection in second position limiting structure, and cooperate with the structure that is rotatably assorted, it rotates and matches between the first position limiting structure and movable position limiting structure Close, namely can relatively rotate therebetween, enable movable axis 21 relative to the rotation of hollow shaft 11, and component to be driven also with it is hollow Axis 11 is separated from each other, and is not limited by motor 1, can change self-position or posture under the action of other external force.

Preferably, as shown in figure 4, the first position limiting structure can be keyway 211, the extending direction of the keyway 211 is activity The axial direction of axis 21, keyway 211 are arranged with respect to the outer surface depressions of movable axis 21；The structure that is rotatably assorted can be the interior of hollow shaft 11 Surface, it is clear that when the first position limiting structure and the structure that is rotatably assorted match, hollow shaft 11 and movable axis 21 can be relatively rotated； Second position limiting structure is positive stop key 113, and it relatively rotates fit structure, i.e. the inner surface of hollow shaft 11 protrudes setting, limit Key 113 can stretch in keyway 211, and be cooperated by limiting with keyway 211, make hollow shaft 11 and movable axis 21 in hollow shaft 11 Rotation direction on formed limit matching relationship；And in order to guarantee that positive stop key 113 can be deviate from out of keyway 211, keyway can be made 211 at least one end in the opposite end of aforementioned axial have opening 212, so as to by change movable axis 21 with it is hollow Relative position of the axis 11 in the axial direction of hollow shaft 11, deviates from positive stop key 113 out of keyway 211, to break 11 He of hollow shaft Limit connection relationship between movable axis 21.Specifically, during design and production, keyway 211 and positive stop key can be made 113 shape and every size are adapted, to make the two that can form limit matching relationship.

Further, during movable axis 21 protrudes into hollow shaft 11 under the action of function part 22 in order to prevent, because used Property etc. factors there is offside situation, may cause motor 1 in driving mechanism or other component damage, it is preferable that such as Fig. 4 institute Show, keyway 211 is provided with holding section 213 on the direction of opening 212, and holding section 213 and positive stop key are in hollow shaft 11 Axial upper limit cooperation, and then in movable axis 21 and hollow shaft 11 during relative motion in the axial direction of hollow shaft 11, it is right The position of movable axis 21 is limited, and prevents hollow shaft 11 from crossing setting position under the action of the factors such as inertia, and damages electricity The components such as machine 1.

In addition, in order to be adapted to the hollow shaft 11 of different model and size, the second position limiting structure can be with the axis of hollow shaft 11 Body is formed using seperated molding mode, and in order to promote the convenience of assembling, is also provided with stop collar 111, stop collar 111 can be using the hardness such as metal, wear resistance and the higher material manufacture of resistance to deformation degree, to prevent the driving mechanism from working Stop collar 111 is damaged after a period of time；Second position limiting structures such as positive stop key 113 can connect the through hole in stop collar 111 Inner wall on, so that positive stop key 113 and stop collar 111 be made to form integral structure, and according to the difference of size, be adapted to different model It with the axis body 112 of the hollow shaft 11 of size, can be connected by connector therebetween, along the axial direction of hollow shaft 11, stop collar 111 and the open end of axis body 112 be located at the opposite end of hollow shaft 11, thus in the assembling of the driving mechanism and worked Cheng Zhong, during so that movable axis 21 is stretched out hollow shaft 11 from open end, position is limited in holding section 213 and positive stop key At the position of 113 cooperations.

In order to further enhance the limit fiting effect between movable axis 21 and hollow shaft 11, it is preferable that 113 He of positive stop key Keyway 211 can be set multiple, and multiple positive stop keys 113 can be arranged along the rotation direction interval of hollow shaft 11, in the drive In the course of work of motivation structure, multiple positive stop keys 113 can be made to correspond with multiple keyways 211 and cooperated, to be promoted hollow The reliability of limit connection relationship between axis 11 and movable axis 21.For example, keyway 211 can be set there are two, three or more It is multiple, and in order to promote the uniform force of each positive stop key 113, it is preferable that multiple keyways 211 can be along the rotation of movable axis 21 Direction is uniformly distributed.In addition, the quantity of keyway 211 is excessive in order to prevent, and cause keyway 211 cell wall and positive stop key 113 it Between limit reliability reduce it is excessive, it is preferable that two or three have can be set in keyway 211.

Further, in the axial direction of hollow shaft 11, the maximum length of positive stop key 113 can be made to be less than movable axis 21 opposite The maximum activity distance of hollow shaft 11 makes the maximum length of positive stop key 113 be less than the maximum length of keyway 211 in other words, thus It prevents from occurring positive stop key 113 during movable axis 21 is rotated relative to hollow shaft 11 and even producing with 21 phase mutual friction of movable axis Raw the case where hindering, after guaranteeing that positive stop key 113 and keyway 211 are separated from each other, movable axis 21 can be almost unhinderedly relatively empty Mandrel 11 rotates.

Further, as depicted in figs. 1 and 2, driving mechanism provided by the present invention can also include retarder 3, at this In the assembling process of driving mechanism, retarder 3 and motor 1 can be made to be sequentially connected, to promote output while reducing revolving speed Torque, and the inertia of load can also be reduced, promote the service life and working performance of entire driving mechanism.Specifically, slow down The model and design parameter of device 3 can be determined according to selected parameter of motor 1 etc., be not construed as limiting herein.In addition, of the invention Provided driving mechanism further includes shell 4, and motor 1, clutch 2 and retarder 3 are installed in shell 4, by shell 4 Certain protective effect is provided aforementioned three, prevents extraneous component from having an adverse effect to the work of driving mechanism, is promoted whole The service life and working performance of a driving mechanism.

Based on driving mechanism provided by any of the above-described embodiment, the present invention also provides a kind of electrically driven curtains comprising window Curtain axis and any of the above-described driving mechanism, and driving mechanism and curtain axis are sequentially connected.

In the description of the present invention, it should be noted that the orientation or positional relationship of the instructions such as term " on ", "lower" is base In orientation or positional relationship shown in the drawings, it is merely for convenience of description of the present invention and simplification of the description, rather than indication or suggestion Signified device or element must have a particular orientation, be constructed and operated in a specific orientation, therefore should not be understood as to this The limitation of invention.In addition, term " first ", " second " are used for description purposes only, it is not understood to indicate or imply relatively heavy The property wanted.

In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, term " installation " " connects It is logical ", " connection " shall be understood in a broad sense, for example, it may be being fixedly connected, may be a detachable connection, or be integrally connected；It can To be mechanical connection, it is also possible to be electrically connected；It can be direct connection, can also be can be by intermediary indirect communication Connection inside two elements.For the ordinary skill in the art, above-mentioned term can be understood at this with concrete condition Concrete meaning in invention.In addition, in the description of the present invention, unless otherwise indicated, the meaning of " plurality " is two or two More than.

The foregoing is merely presently preferred embodiments of the present invention, is not intended to limit the invention, it is all in spirit of the invention and Within principle, any modification, equivalent replacement, improvement and so on be should all be included in the protection scope of the present invention.

Claims (10)

1. a kind of driving mechanism characterized by comprising

Motor (1), the motor (1) include the hollow shaft (11) with open end；

Clutch (2), the clutch (2) include movable axis (21) and function part (22), and the movable axis (21) is opened described in Mouth end is protruded into the hollow shaft (11), and is matched with the function part (22), and the movable axis (21) is for driving wait drive Dynamic component, the function part (22) for make the movable axis (21) and the hollow shaft (11) it is relatively fixed or relative rotation.

2. driving mechanism according to claim 1, which is characterized in that the function part (22) includes electromagnet and magnetism Portion, the electromagnet and the hollow shaft (11) are relatively fixed, and the magnetic portion is connect with the movable axis (21),

In the state that the electromagnet and the magnetic portion are mutually attracted, the movable axis (21) is arranged to and the hollow shaft (11) relatively fixed；

In the state that the electromagnet and the magnetic portion are separated from each other, the movable axis (21) is arranged to and the hollow shaft (11) it relatively rotates.

3. driving mechanism according to claim 1, which is characterized in that the function part (22) include electromagnet (221) and Iron block (222), the electromagnet (221) and the hollow shaft (11) are relatively fixed, the axial direction and gravity of the movable axis (21) Direction is identical, and the iron block (222) is located at the lower section of the electromagnet (221), and connect with the movable axis (21),

In the state that the electromagnet (221) and the iron block (222) are attracted, the movable axis (21) is arranged to and the sky Mandrel (11) is relatively fixed；

In the state that the electromagnet (221) is separated with the iron block (222), the movable axis (21) is arranged to and the sky Mandrel (11) relatively rotates.

4. driving mechanism described in any one of -3 according to claim 1, which is characterized in that be arranged on the movable axis (21) There is the first position limiting structure, there is the second position limiting structure and the structure that is rotatably assorted on the hollow shaft (11), in the hollow shaft (11) in rotation direction, first position limiting structure and second position limiting structure limit cooperation or first limit are tied Structure and the structure movement cooperation that is rotatably assorted.

5. driving mechanism according to claim 4, which is characterized in that first position limiting structure is along the movable axis (21) axially extending keyway (211), the outer surface depressions of the relatively described movable axis (21) of the keyway (211), and it is described At least one end of keyway (211) in the axially opposing both ends has opening (212)；

The inner surface that structure is the hollow shaft (11) that is rotatably assorted, second position limiting structure is positive stop key (113), institute State the relatively described structure protrusion that is rotatably assorted of positive stop key (113), and the positive stop key (113) with the keyway (211) described The rotation direction upper limit of hollow shaft (11) cooperates.

6. driving mechanism according to claim 5, which is characterized in that the keyway (211) is away from the opening (212) One end is provided with holding section (213), and the holding section (213) is with the positive stop key (113) along the axial direction of the hollow shaft (11) Limit cooperation.

7. driving mechanism according to claim 5, which is characterized in that the keyway (211) and the positive stop key (113) are equal Be provided with it is multiple, multiple positive stop keys (113) along the hollow shaft (11) rotation direction interval be arranged, multiple keyways (211) and multiple positive stop keys (113) correspond cooperation.

8. driving mechanism according to claim 5, which is characterized in that in the axial direction of the hollow shaft (11), the limit The maximum length of position key (113) is less than the maximal translation distance of the movable axis (21) relatively described hollow shaft (11).

9. driving mechanism described in any one of -3 according to claim 1, which is characterized in that it further include retarder (3), it is described Retarder (3) and the motor (1) are sequentially connected.

10. a kind of electrically driven curtain, which is characterized in that including driving machine described in any one of curtain axis and claim 1-9 Structure, the driving mechanism and the curtain axis are sequentially connected.