Summary of the invention
The invention provides a kind of control method of electric tool, can be totally released on bolt but not removal nut.
To achieve the above object of the invention, the invention provides a kind of control method of electric tool, wherein electric tool comprises motor and connects the output shaft of motor, and described control method comprises the steps: to detect the parameter x for representing output shaft load; Meet according to described parameter x and pre-conditionedly judge that described output shaft load reduction is to being equal to or less than default load, and then change the rotating speed of described motor.
Preferably, described parameter x is the current value of supply motor; Describedly pre-conditionedly to comprise: the current value of described supply motor is equal to or less than predetermined current threshold.
Preferably, described predetermined current threshold is the current value of described electric tool when light condition.
Preferably, described parameter x is output torque value; Describedly pre-conditionedly be: described output torque value is equal to or less than predetermined torque threshold value.
Preferably, described parameter x is motor speed value; Describedly pre-conditionedly be: described motor speed value is equal to or greater than preset rotation speed threshold value.
Preferably, described parameter x is the accekeration of electric tool; Describedly pre-conditionedly be: described accekeration is equal to or less than predetermined acceleration threshold value.
Preferably, electric motor starting in described electric tool after the second preset duration, starts to detect the parameter x for representing output shaft load.
Preferably, described control method also comprises the following steps before the parameter x detected for representing output shaft load: preset speed governing requirement command collection, it comprises multiple speed governing requirement command, the concrete mode of one of the step of the rotating speed of the corresponding described change motor of each speed governing requirement command; Obtain user's speed governing requirement command; The concrete mode of the step of described change motor speed is confirmed according to user's speed governing requirement command.
Preferably, the concrete mode of the step of the rotating speed of described change motor is: control motor and periodically switch between rotating and reverse.
Preferably, the concrete mode of the step of the rotating speed of described change motor comprises: with electric tool motor startup for starting at the moment, obtain described parameter x meet described pre-conditioned time object time; When object time is after predetermined time, after the first preset duration, closing down motor.
Preferably, the concrete mode of the step of the rotating speed of described change motor comprises: with electric tool motor startup for starting at the moment, obtain described parameter x meet described pre-conditioned time object time; When object time is after predetermined time, after motor rotation predetermined amount, close down motor.
Preferably, the concrete mode of the step of the rotating speed of described change motor comprises: with electric tool motor startup for starting at the moment, obtain described parameter x meet described pre-conditioned time object time; When object time is after predetermined time, reduce motor speed.
Preferably, the concrete mode of the step of the rotating speed of described change motor comprises: with electric tool motor startup for starting at the moment, obtain described parameter x meet described pre-conditioned time object time; When object time is before predetermined time, immediately close down motor.
Compared with prior art, the control method of electric tool provided by the present invention, nut and bolt can be totally released but to make nuts and bolt be separated, and user can manual separation nuts and bolt according to demand, meets the special operation condition demand that user only needs to unclamp nut.
The invention provides a kind of control system of electric tool, can be totally released on bolt but not removal nut.
To achieve the above object of the invention, the invention provides a kind of control system of electric tool, wherein, electric tool comprises motor and connects the output shaft of motor, and described control system comprises: detection module, detects the parameter x for representing output shaft load; Control module, comprising: parameter judges submodule, meets pre-conditionedly judge that described output shaft load reduction is to being equal to or less than default load according to described parameter x; Electrical motor gearshift submodule, and then the rotating speed changing described motor.
Preferably, described parameter x is the current value of supply motor; Describedly pre-conditionedly to comprise: the current value of described supply motor is equal to or less than predetermined current threshold.
Preferably, described predetermined current threshold is the current value of described electric tool when light condition.
Preferably, described parameter x is output torque value; Describedly pre-conditionedly be: described output torque value is equal to or less than predetermined torque threshold value.
Preferably, described parameter x is motor speed value; Describedly pre-conditionedly be: described motor speed value is equal to or greater than preset rotation speed threshold value.
Preferably, described parameter x is the accekeration of electric tool; Describedly pre-conditionedly be: described accekeration is equal to or less than predetermined acceleration threshold value.
Preferably, electric motor starting in described electric tool after the second preset duration, described detection module starts to detect the parameter x for representing output shaft load.
Preferably, described control system also comprises presetting module, and described presetting module comprises: submodule is preset in instruction, for default speed governing requirement command collection, it comprises multiple speed governing requirement command, the concrete mode of one of the step of the rotating speed of the corresponding described change motor of each speed governing requirement command; Instruction obtains submodule, for obtaining user's speed governing requirement command; Instructions match submodule, for confirming the concrete mode of the step of described change motor speed according to user's speed governing requirement command.
Preferably, described electrical motor gearshift submodule specifically for: control motor and periodically switch between rotating and reverse.
Preferably, described electrical motor gearshift submodule comprises: moment acquiring unit, with electric tool motor startup for starting at the moment, obtain described parameter x meet described pre-conditioned time object time; Moment judging unit, judges object time whether after predetermined time; Motor control unit, when object time is whether after predetermined time, closes down motor after the first preset duration.
Preferably, described electrical motor gearshift submodule comprises: moment acquiring unit, with electric tool motor startup for starting at the moment, obtain described parameter x meet described pre-conditioned time object time; Moment judging unit, judges object time whether after predetermined time; Motor control unit, when object time is whether after predetermined time, closes down motor after controlling motor rotation predetermined amount.
Preferably, described electrical motor gearshift submodule comprises: moment acquiring unit, with electric tool motor startup for starting at the moment, obtain described parameter x meet described pre-conditioned time object time; Moment judging unit, judges object time whether after predetermined time; Motor control unit, when object time is whether after predetermined time, reduces motor speed.
Preferably, described electrical motor gearshift submodule comprises: moment acquiring unit, with electric tool motor startup for starting at the moment, obtain described parameter x meet described pre-conditioned time object time; Moment judging unit, judges object time whether after predetermined time; Motor control unit, when object time is whether after predetermined time, closes down motor immediately.
Compared with prior art, the control system of electric tool provided by the present invention, nut and bolt can be totally released but to make nuts and bolt be separated, and user can manual separation nuts and bolt according to demand, meets the special operation condition demand that user only needs to unclamp nut.
The invention provides a kind of electric tool, can be totally released on bolt but not removal nut.
To achieve the above object of the invention, the invention provides a kind of electric tool, wherein, described electric tool comprises: power supply; Motor, obtains the electric power of power supply to provide rotary power; Output shaft, obtains the rotary power of motor and exports; Control system described in foregoing summary, described control system and motor and power supply are electrically connected.
Preferably, described electric tool also comprises: system activation member, and it is for the described control system of exercisable startup.
Compared with prior art, electric tool provided by the present invention, can be totally released nut and bolt and nuts and bolt but can not be made to be separated, and user can manual separation nuts and bolt according to demand, meets the special operation condition demand that user only needs to unclamp nut.
Embodiment
Describe the present invention below with reference to embodiment shown in the drawings.But these embodiments do not limit the present invention, the structure that those of ordinary skill in the art makes according to these embodiments, method or conversion functionally are all included in protection scope of the present invention.
Control method provided by the present invention and control system can be applicable to polytype electric tool, below main with electric impact wrench 10 for specific embodiment is described.
Shown in ginseng Fig. 1, in one embodiment of the invention, the output shaft 16 that electric impact wrench 10 comprises motor 12, working head 14 and is connected between motor 12 and working head 14; The working head 14 of electric impact wrench 10 drives removal framing scaffold 20 top nut 32 at motor 12, thus nut 32 and bolt 34 will be made to unclamp, and is convenient to dismantle framing scaffold 20.
Also be provided with control system 40a in electric impact wrench 10, control system 40a is positioned on circuit board, for when electric impact wrench 10 carries out nut 32 removal, controls the rotating speed of motor 12.
Shown in ginseng Fig. 2, in the first embodiment of control system provided by the present invention, control system 40a comprises detection module 42 and control module 44.
Detection module 42 represents the parameter x of output shaft 16 load for detecting.
Electric impact wrench 10 to carry out in the process of fastening or removal in torque nut 32 to it, due to the existence of the screw threads for fastening power between nut 32 and bolt 34, nut 32 can apply a moment of resistance by the output shaft 16 of working head 14 pairs of electric impact wrenches 10, when the driving torque that motor 12 exports in electric impact wrench 10 overcomes this moment of resistance, working head 14 starts fastening or removal nut 32.
The moment of resistance is directly proportional to the screw threads for fastening power between nut 32 and bolt 34, be screwed in the process of bolt 34 at nut 32, between nut 32 and bolt 34, screw threads for fastening power also increases gradually, and when nut 32 and bolt 34 are fully tightened, screw threads for fastening power reaches peak value; Otherwise, in the process of electric impact wrench 10 removal nut 32, screw threads for fastening power is in peak value, initial time, the moment of resistance that the output shaft 16 of electric impact wrench 10 bears is maximum, motor 12 in electric impact wrench 10 is now needed to export larger driving torque to overcome the moment of resistance being positioned at peak value, after nut 32 and bolt 34 depart from and tighten completely, the moment of resistance that the output shaft 16 of electric impact wrench 10 bears is reduced to gently, and the driving torque that motor 12 exports also synchronously is reduced to gently.
Parameter x is for representing the load of electric impact wrench 10 output shaft 16, namely for representing the moment of resistance that electric impact wrench 10 output shaft 16 bears, because the moment of resistance remains consistent with the output torque of electric impact wrench 10 motor 12, by calling the parameter relevant to motor 12 output torque as aforementioned parameters x, then can realize the size of the load being identified output shaft 16 by monitoring parameter x.
Control module 44 pre-conditionedly judges that described output shaft load reduction is to being equal to or less than default load for meeting according to described parameter x, and then changes the rotating speed of described motor 12.
Wherein, control module 44 comprises parameter and judges submodule 442 and electrical motor gearshift submodule 444; Parameter judges submodule 442 monitoring parameter x, judge whether the value of parameter x meets pre-conditioned, confirm on output shaft 16, whether load has been reduced to default load based on aforementioned judged result, if, motor speed is changed by electrical motor gearshift submodule 444, if not, detection module 42 obtains current parameter x again, and parameter judges submodule 442 and then judge whether current parameter x meets pre-conditioned.
Shown in ginseng Fig. 3, Fig. 3 describe adopt electric impact wrench 10 removal to be combined with bolt 34 more closely nut 32 time, supply the electric current curve over time of its motor 12; Wherein, alphabetical t represents the time that motor 12 is started working, and alphabetical i represents the current value of the motor 12 being supplied to electric impact wrench 10.
Curve in Fig. 3 comprises Part I A, the first flex point H, Part II B, Second Inflexion Point I, Part III C, the 3rd flex point J, Part IV D, Part V E and Part VI F.
Wherein Part I A is one section of upcurve, and it represents that motor 12 has just started to start, and now nut 32 applies the moment of resistance not yet to working head 14, and Part I A can think linear substantially; That follow hard on Part I A is the first flex point K and follow-up Part II B, first flex point K has a downward-sloping sudden change relative to Part I A, Part II B is a decline curve, this represents that nut 32 has started to push against with working head 14, and nut 32 pairs of working heads 14 apply the moment of resistance; After Second Inflexion Point I, entering the Part III C of basic horizontal, now working head 14 starts to overcome the moment of resistance to the nut 32 that comes up; As time goes on, there is downward transition at the 3rd flex point J place in Part III C, and form the Part IV D obviously declined, and now nut 32 is close to being fully released; Enter Part V E subsequently, this part is the straight line of one section of level substantially, and show that nut 32 is fully released, motor 12 is in light condition, finally enters Part VI F, and now motor 12 is closed down, and current i also reduces to 0.
Ginseng Fig. 4 shown in, Fig. 4 describe adopt electric impact wrench 10 at removal when bolt 34 is in conjunction with loose nut 32, supply the electric current curve over time of its motor 12; Wherein, alphabetical t represents the time that motor 12 is started working, and alphabetical i represents the current value of the motor 12 being supplied to electric impact wrench 10.
Wherein initial part M is one section of upcurve, and it represents that motor 12 has just started to start, and now nut 32 applies the moment of resistance not yet to working head 14, and initial part M can think linear substantially; Follow hard on the follow-up center section N of initial part F, center section N is a decline curve, and this represents that nut 32 has started to push against with working head 14, and nut 32 pairs of working heads 14 apply the moment of resistance; Because nut 32 and bolt 34 combine not tight, just nut 32 and bolt 34 is made to unclamp in working head 14 very short time, now directly enter the part (non-label) of basic horizontal, this part is the straight line of one section of level substantially, show that nut 32 is fully released, motor 12 is in light condition; Finally enter last part O, now motor 12 is closed down, and current i also reduces to 0.
In first embodiment of the invention, parameter x is the current value of motor 12 in supply electric impact wrench 10, aforementioned pre-conditioned, is: in supply electric impact wrench 10, the current value of motor 12 is equal to or less than predetermined current threshold.
Current curve in composition graphs 3 and Fig. 4, set pre-conditioned in predetermined current threshold be current value I0 when motor 12 is unloaded in Part V E in Fig. 3, be equally also current value I0 when motor 12 is unloaded in last part 0 in Fig. 4; The current value as parameter x drop to motor 12 unloaded time current value time I0, show that nut 32 unclamps with bolt 34, electrical motor gearshift submodule 444 and then change the rotating speed of motor 12.
It should be noted that: the current value obtaining supply motor 12 is by multi collect current value and obtain the mode of mean value, thus reduce the current value error that current fluctuation causes, do not repeat at this.
Certainly, in other embodiments of the present invention, predetermined current threshold is not limited to current value I0 during aforementioned motor 12 zero load, also can slightly larger than or be less than this no-load current value I0, now nut 32 and bolt 34 are also close to being totally released, in nut 32 pairs of electric impact wrenches 10, the moment of resistance of output shaft 16 is also close to moment of resistance time unloaded, can ensure the control accuracy to electric impact wrench 10 equally.
In first embodiment of the invention, electrical motor gearshift submodule 444 also comprises moment acquiring unit 4442, moment judging unit 4444 and motor control unit 4446.
As starting at the moment when starting using electric tool motor, moment acquiring unit 4442 starts timing, when the current value supplying motor 12 in electric impact wrench 10 is equal to or less than predetermined current threshold, moment acquiring unit 4442 generates the current moment and exports moment judging unit 4444 to as object time T2, predetermined time T1 is stored in moment judging unit 4444, according to the front and back of object time T2 and predetermined time T1, motor control unit 4446 selects the mode of different change motor speeds.
According to Fig. 3, because nut 32 is combined tightr with bolt 34, object time T2 is after predetermined time T1, and moment judging unit 4444 exports corresponding steering order to motor control unit 4446, and then motor control unit 4446 closes down motor 12 after the first preset duration; Thus fully unclamp nut 32 and bolt 34, but the two can not depart from again.
This first preset duration can be arranged to departing from stroke needed for bolt completely from current location according to nut 32, and with at the end of the first preset duration, nut 32 also still can not depart from bolt 34 for benchmark; Preferably, the first preset duration is 10 milliseconds.
According to Fig. 4, because nut 32 is combined loosely with bolt 34, object time T2 is before predetermined time T1, and moment judging unit 4444 exports another steering order to motor control unit 4446, and then motor control unit 4446 closes down motor 12 immediately; Thus prevent excessive nut 32 and bolt 34 and the two is departed from.
It should be noted that: described " closing down motor " comprises stopping to motor and brake above, does not repeat at this.
Selected the mode of different change motor 12 rotating speeds for different object time T2 by basis, at nut 32, nut 32 can be produced to greatest extent in bolt 34, but can not be separated with bolt 34, reduce the time spent by the manual removal nut 32 of user, significantly improve Consumer's Experience.
Shown in ginseng Fig. 5, in second embodiment of control system provided by the present invention, control system 40b is compared with other embodiments of the present invention, difference is only: control system 40b also comprises presetting module 41, and this presetting module 41 comprises instruction and presets submodule 412, instruction acquisition submodule 414 and instructions match submodule 416.
Wherein, instruction presets submodule 412 for default speed governing requirement command collection, and it comprises multiple speed governing requirement command, the concrete mode of one of the step of the rotating speed of the corresponding described change motor of each speed governing requirement command; Instruction obtains submodule 414 for obtaining user's speed governing requirement command; Instructions match submodule 416 is for confirming the concrete mode of the step of described change motor speed according to user's speed governing requirement command.
Follow-up, the mode that electrical motor gearshift submodule 444 confirms according to instructions match submodule 416 changes motor speed.
Stroke according to nut complete removal on bolt sets different speed change patterns, such as, Long travel is set as the first speed change pattern, by, short stroke is set as the second speed change pattern; User, according to the different strokes of nut, sends best user's speed governing requirement command, and then obtains the pattern of most suitable change motor speed; Subsequently, speed-variable module changes motor speed by this gear shift mode.
Make user can select to change according to operating mode the mode of motor speed, improve the adaptive faculty of control system to different operating mode, thus ensure that under different operating mode, nut total energy removal is to optimum position.
Preferably, switch toggle by arranging pattern on electric impact wrench and in toggle week side dimension model diagram, be convenient to user and operate the speed change pattern that toggle selects correspondence in advance before use.
Shown in ginseng Fig. 6, in 3rd embodiment of control system provided by the present invention, control system 40c is relative to the first embodiment, difference is: control system 40c also comprises clock module 43, this clock module 43 for providing start time, and controls detection module at this start time start detection parameter x.
Wherein, start time is the timing node after electric tool start after the second preset duration.
Current curve in composition graphs 3 and Fig. 4, aforesaid time starting point can be the T0 moment, and the current i in T0 moment is arranged in Fig. 3 Part II B and Fig. 4 center section N; Before the T0 time, control system does not start, and in the T0 moment, control system starts to start, and to be got parms x by its detection module.
Certainly, the second preset duration also can be 0, and aforesaid time starting point was for 0 moment.
By setting the second preset duration, when control system is started, working head pushes against with nut, and nut has started to apply the moment of resistance to working head, and nut is about to be come up; Control system can be detected faster, and parameter x meets the pre-conditioned moment, avoid in Part I A or initial part M, working head does not also push against with nut, the low and energy dissipation of cause control system there is no work efficiency that work requirements causes.
In 4th embodiment of control system provided by the present invention, control system is compared with the first embodiment, and difference is only: parameter x is the output torque value of motor, pre-conditionedly comprises: the output torque value of motor is equal to or less than predetermined torque threshold value.
Detect motor output torque value to obtain by torque sensor; And using the output torque of motor during zero load as predetermined torque threshold value.
In 5th embodiment of control system provided by the present invention, control system is compared with the first embodiment, and difference is only: parameter x is the tachometer value of motor, pre-conditionedly comprises: the tachometer value of motor is equal to or greater than preset rotation speed threshold value.
Detect motor speed value to obtain by Rotating speed measring elements such as Hall element, magnetic nails; And using the rotating speed of motor during zero load as preset rotation speed threshold value.
In 6th embodiment of control system provided by the present invention, control system is compared with the first embodiment, difference is only: parameter x is the accekeration of electric tool, this accekeration, caused by electric tool vibrations, pre-conditionedly to comprise: the acceleration of output shaft is equal to or less than predetermined acceleration threshold value
Detect output shaft accekeration by arranging acceleration transducer to obtain in instrument, using the rotating speed of motor during zero load as preset rotation speed threshold value.
In 7th embodiment of control system provided by the present invention, control system compared with previous embodiment, parameter x corresponding in control system and pre-conditionedly adopt mode mentioned any one of the aforementioned first to the 6th embodiment; Difference is: parameter x meet pre-conditioned residing object time T2 after predetermined time T1 time, electrical motor gearshift submodule 444 closes down motor after motor rotation predetermined amount.
In 8th embodiment of control system provided by the present invention, control system is compared with the 7th embodiment, difference is only: parameter x meet pre-conditioned residing object time T2 after predetermined time T1 time, electrical motor gearshift submodule 444 closes down motor after reducing motor speed.
In 9th embodiment of control system provided by the present invention, control system is compared with the 7th embodiment, difference is only: parameter x meet pre-conditioned residing object time T2 after predetermined time T1 time, electrical motor gearshift submodule 444 reduces motor speed, reduce prompting user by rotating speed, make user manually close down motor.
In tenth embodiment of control system provided by the present invention, control system is compared with the 7th embodiment, difference is only: no matter parameter x meet pre-conditioned residing object time T2 after predetermined time T1 or before, electrical motor gearshift submodule 444 is all by making motor periodically switch between rotating and reverse continuously, point out user, make user manually close down motor.
Compared with prior art, in embodiments of the invention, nut and bolt can unclamp and nuts and bolt but can not be made to be separated by control system, and user can manual separation nuts and bolt according to demand, meets the special operation condition demand that user only needs to unclamp nut.
Shown in ginseng Fig. 7, in first embodiment of the invention, the control method of electric tool comprises the steps:
Step S20, detects the parameter x representing output shaft 16 load.
Electric impact wrench 10 to carry out in the process of fastening or removal in torque nut 32 to it, due to the existence of the screw threads for fastening power between nut 32 and bolt 34, nut 32 can apply a moment of resistance by the output shaft 16 of working head 14 pairs of electric impact wrenches 10, when the driving torque that motor 12 exports in electric impact wrench 10 overcomes this moment of resistance, working head 14 starts fastening or removal nut 32.
The moment of resistance is directly proportional to the screw threads for fastening power between nut 32 and bolt 34, be screwed in the process of bolt 34 at nut 32, between nut 32 and bolt 34, screw threads for fastening power also increases gradually, and when nut 32 and bolt 34 are fully tightened, screw threads for fastening power reaches peak value; Otherwise, in the process of electric impact wrench 10 removal nut 32, screw threads for fastening power is in peak value, initial time, the moment of resistance that the output shaft 16 of electric impact wrench 10 bears is maximum, motor 12 in electric impact wrench 10 is now needed to export larger driving torque to overcome the moment of resistance being positioned at peak value, after nut 32 and bolt 34 depart from and tighten completely, the moment of resistance that the output shaft 16 of electric impact wrench 10 bears is reduced to gently, and the driving torque that motor 12 exports also synchronously is reduced to gently.
Parameter x is for representing the load of electric impact wrench 10 output shaft 16, namely for representing the moment of resistance that electric impact wrench 10 output shaft 16 bears, because the moment of resistance remains consistent with the output torque of electric impact wrench 10 motor 12, by calling the parameter relevant to motor 12 output torque as aforementioned parameters x, then can realize the size of the load being identified output shaft 16 by monitoring parameter x.
Enter step S40 subsequently, meet according to described parameter x and pre-conditionedly judge that described output shaft load reduction is to being equal to or less than default load, and then change the rotating speed of described motor
Wherein, step S40 specifically comprises:
S42, monitoring parameter x, judge whether the value of parameter x meets pre-conditioned, confirms on output shaft 16, whether load has been reduced to default load based on aforementioned judged result, if so, performs S44 step;
S44, change the rotating speed of described motor.
Shown in ginseng Fig. 3, Fig. 3 describe adopt electric impact wrench 10 removal to be combined with bolt 34 more closely nut 32 time, supply the electric current curve over time of its motor 12; Wherein, alphabetical t represents the time that motor 12 is started working, and alphabetical i represents the current value of the motor 12 being supplied to electric impact wrench 10.
Curve in Fig. 3 comprises Part I A, the first flex point H, Part II B, Second Inflexion Point I, Part III C, the 3rd flex point J, Part IV D, Part V E and Part VI F.
Wherein Part I A is one section of upcurve, and it represents that motor 12 has just started to start, and now nut 32 applies the moment of resistance not yet to working head 14, and Part I A can think linear substantially; That follow hard on Part I A is the first flex point K and follow-up Part II B, first flex point K has a downward-sloping sudden change relative to Part I A, Part II B is a decline curve, this represents that nut 32 has started to push against with working head 14, and nut 32 pairs of working heads 14 apply the moment of resistance; After Second Inflexion Point I, entering the Part III C of basic horizontal, now working head 14 starts to overcome the moment of resistance to the nut 32 that comes up; As time goes on, there is downward transition at the 3rd flex point J place in Part III C, and form the Part IV D obviously declined, and now nut 32 is close to being fully released; Enter Part V E subsequently, this part is the straight line of one section of level substantially, and show that nut 32 is fully released, motor 12 is in light condition, finally enters Part VI F, and now motor 12 is closed down, and current i also reduces to 0.
Ginseng Fig. 4 shown in, Fig. 4 describe adopt electric impact wrench 10 at removal when bolt 34 is in conjunction with loose nut 32, supply the electric current curve over time of its motor 12; Wherein, alphabetical t represents the time that motor 12 is started working, and alphabetical i represents the current value of the motor 12 being supplied to electric impact wrench 10.
Wherein initial part M is one section of upcurve, and it represents that motor 12 has just started to start, and now nut 32 applies the moment of resistance not yet to working head 14, and initial part M can think linear substantially; Follow hard on the follow-up center section N of initial part F, center section N is a decline curve, and this represents that nut 32 has started to push against with working head 14, and nut 32 pairs of working heads 14 apply the moment of resistance; Because nut 32 and bolt 34 combine not tight, just nut 32 and bolt 34 is made to unclamp in working head 14 very short time, now directly enter the part (non-label) of basic horizontal, this part is the straight line of one section of level substantially, show that nut 32 is fully released, motor 12 is in light condition; Finally enter last part O, now motor 12 is closed down, and current i also reduces to 0.
In first embodiment of the invention, parameter x is the current value of motor 12 in supply electric impact wrench 10, aforementioned pre-conditioned, is: in supply electric impact wrench 10, the current value of motor 12 is equal to or less than predetermined current threshold.
Current curve in composition graphs 3 and Fig. 4, set pre-conditioned in predetermined current threshold be current value I0 when motor 12 is unloaded in Part V E in Fig. 3, be equally also current value I0 when motor 12 is unloaded in last part 0 in Fig. 4; The current value as parameter x drop to motor 12 unloaded time current value I0 time, show that nut 32 unclamps with bolt 34, and then change the rotating speed of motor 12.
It should be noted that: the current value obtaining supply motor 12 is by multi collect current value and obtain the mode of mean value, thus reduce the current value error that current fluctuation causes, do not repeat at this.
Certainly, in other embodiments of the present invention, predetermined current threshold is not limited to current value I0 during aforementioned motor 12 zero load, also can slightly larger than or be less than this no-load current value I0, now nut 32 and bolt 34 are also close to being totally released, in nut 32 pairs of electric impact wrenches 10, the moment of resistance of output shaft 16 is also close to moment of resistance time unloaded, can ensure the control accuracy to electric impact wrench 10 equally.
In first embodiment of control method provided by the present invention, aforementioned S44 specifically comprises the steps:
S442, when starting using electric tool motor as starting at the moment, when the current value supplying motor 12 in electric impact wrench 10 is equal to or less than predetermined current threshold, obtain the current moment and as object time T2;
S444, judge object time T2 before predetermined time T1 or after, if after which, perform S446, if before it, perform S448;
S446, after the first preset duration, close down motor 12;
S448, immediately close down motor 12.
According to Fig. 3, because nut 32 is combined comparatively tight with bolt 34, object time T2, after predetermined time T1, closes down motor 12 by S446 after the first preset duration; Thus fully unclamp nut 32 and bolt 34, but the two can not depart from again.
This first preset duration can be arranged to departing from stroke needed for bolt completely from current location according to nut 32, and with at the end of the first preset duration, nut 32 also still can not depart from bolt 34 for benchmark; Preferably, the first preset duration is 10 milliseconds.
According to Fig. 4, because nut 32 is combined loosely with bolt 34, object time T2, before predetermined time T1, closes down motor 12 immediately by S448; Thus prevent excessive nut 32 and bolt 34 and the two is departed from.
It should be noted that: described " closing down motor " comprises stopping to motor and brake two steps above, does not repeat at this.
Selected the mode of different change motor 12 rotating speeds for different object time T2 by basis, at nut 32, nut 32 can be produced to greatest extent in bolt 34, but can not be separated with bolt 34, reduce the time spent by the manual removal nut 32 of user, significantly improve Consumer's Experience.
Shown in ginseng Fig. 8, in the second embodiment of control method provided by the present invention, control method is compared with other embodiments of the present invention, and difference is only: control method also comprises the step S10 before being positioned at step S20, and it specifically comprises:
S12, default speed governing requirement command collection, it comprises multiple speed governing requirement command, the concrete mode of one of the step of the rotating speed of the corresponding described change motor of each speed governing requirement command;
S14, acquisition user speed governing requirement command;
S16, confirm the concrete mode of the step of described change motor speed according to user's speed governing requirement command.
Stroke according to nut complete removal on bolt sets different speed change patterns, such as, Long travel is set as the first speed change pattern, by, short stroke is set as the second speed change pattern; User, according to the different strokes of nut, sends best user's speed governing requirement command, and then obtains the pattern of most suitable change motor speed; Later step S80 changes motor speed by this gear shift mode.
Make user can select to change according to operating mode the mode of motor speed, improve the adaptive faculty of control method to different operating mode, thus ensure that under different operating mode, nut total energy removal is to optimum position.
Preferably, switch toggle by arranging pattern on electric impact wrench and in toggle week side dimension model diagram, be convenient to user and operate the speed change pattern that toggle selects correspondence in advance before use.
Shown in ginseng Fig. 9, in 3rd embodiment of control method provided by the present invention, control method method is relative to the first embodiment, and difference is: control method also comprises step S30, this step S30 specifically comprises: provide start time, and step S20 starts at this start time.
Wherein, start time is the timing node after electric tool start after the second preset duration.
Current curve in composition graphs 3 and Fig. 4, aforesaid time starting point can be the T0 moment, and the current i in T0 moment is arranged in Fig. 3 Part II B and Fig. 4 center section N; Before the T0 time, control method does not start, and in the T0 moment, starts to start its step S20.
Certainly, the second preset duration also can be 0, and aforesaid time starting point was for 0 moment.
By setting the second preset duration, when control method is started, working head pushes against with nut, and nut has started to apply the moment of resistance to working head, and nut is about to be come up; Control method can be detected faster, and parameter x meets the pre-conditioned moment, avoid in Part I A or initial part M, working head does not also push against with nut, the low and energy dissipation of cause control method there is no work efficiency that work requirements causes.
In 4th embodiment of control method provided by the present invention, control method is compared with the first embodiment, and difference is only: parameter x is the output torque value of motor, pre-conditionedly comprises: the output torque value of motor is equal to or less than predetermined torque threshold value.
Detect motor output torque value to obtain by torque sensor; And using the output torque of motor during zero load as predetermined torque threshold value.
In 5th embodiment of control method provided by the present invention, control method is compared with the first embodiment, and difference is only: parameter x is the tachometer value of motor, pre-conditionedly comprises: the tachometer value of motor is equal to or greater than preset rotation speed threshold value.
Detect motor speed value to obtain by Rotating speed measring elements such as Hall element, magnetic nails; And using the rotating speed of motor during zero load as preset rotation speed threshold value.
In 6th embodiment of control method provided by the present invention, control method is compared with the first embodiment, difference is only: parameter x is the accekeration of electric tool, this accekeration, caused by electric tool vibrations, pre-conditionedly to comprise: the acceleration of output shaft is equal to or less than predetermined acceleration threshold value.
Detect output shaft accekeration by obtaining, using the rotating speed of motor during zero load as preset rotation speed threshold value at instrument built-in acceleration sensor.
In 7th embodiment of control method provided by the present invention, control method is compared with previous embodiment, difference is only: parameter x corresponding in control method and pre-conditionedly adopt mode mentioned any one of the aforementioned first to the 6th embodiment, difference is: parameter x meet pre-conditioned residing object time T2 after predetermined time T1 time, step S446 is adjusted to: after motor rotation predetermined amount, close down motor.
In 8th embodiment of control method provided by the present invention, control method is compared with the 7th embodiment, difference is only: parameter x meet pre-conditioned residing object time T2 before predetermined time T1 time, S446 step is adjusted to: close down motor after reducing motor speed.
In 9th embodiment of control method provided by the present invention, control method is compared with the 7th embodiment, and difference is only: parameter x meet pre-conditioned residing object time T2 after predetermined time T1 time, step S446 is adjusted to: reduce motor speed.Reduce prompting user by rotating speed, make user manually close down motor.
In tenth embodiment of control method provided by the present invention, control method is compared with the 7th embodiment, difference is only: no matter parameter x meet pre-conditioned residing object time T2 after predetermined time T1 or before time, step S446 and S448 all can be adjusted to: motor is periodically switching between rotating and reverse continuously.By pointing out user like this, user is made manually to close down motor.
Compared with prior art, in embodiments of the invention, nut and bolt can unclamp and nuts and bolt but can not be made to be separated by control method, and user can manual separation nuts and bolt according to demand, meets the special operation condition demand that user only needs to unclamp nut.
Be to be understood that, although this instructions is described according to embodiment, but not each embodiment only comprises an independently technical scheme, this narrating mode of instructions is only for clarity sake, those skilled in the art should by instructions integrally, technical scheme in each embodiment also through appropriately combined, can form other embodiments that it will be appreciated by those skilled in the art that.
A series of detailed description listed is above only illustrating for feasibility embodiment of the present invention; they are also not used to limit the scope of the invention, all do not depart from the skill of the present invention equivalent implementations done of spirit or change all should be included within protection scope of the present invention.