CN103210746A

CN103210746A - Electric lawn mower

Info

Publication number: CN103210746A
Application number: CN2012100182439A
Authority: CN
Inventors: 侯巧生
Original assignee: Individual
Current assignee: Individual
Priority date: 2012-01-20
Filing date: 2012-01-20
Publication date: 2013-07-24

Abstract

The invention relates to an electric lawn mower (III). The electric lawn mower comprises a travelling mechanism, a lifting regulating mechanism, a motor, a storage battery, a power supply control switch, a mower cutter and an outer casing. The electric lawn mower is characterized in that the brushless direct current motor controlled by a motor controller is adopted, the storage battery is electrically connected with the motor controller, and the motor controller is electrically connected with the brushless direct current motor and the power supply control switch. The brushless direct current motor is small in size and light in weight, and meanwhile has a ventilation and heat dissipation function; the motor controller is added with a current short-circuit protective circuit, has undervoltage, current limiting and blocking and over-load protective functions, so that the storage battery and the motor are prevented from being burnt, the requirements on the low-revolving-speed large-torque output of the motor can be well met during a lawn mowing process, and the efficiency of the lawn mower is comprehensively improved.

Description

The electric lawn trimmer

Technical field

The present invention relates to graden machine, especially for a kind of be the hand-push type lawn mower of power source with brshless DC motor and accumulator.

Background technology

Existing electric lawn trimmer adopts brush direct current generator and the accumulator power resources as lawn mower, though can in prune in the smooth greenery patches of large tracts of land, bring into play environmental protection and energy saving, prune the high effect of quality, but the brush direct current generator is arranged under situation about running up, anti-load-bearing capacity a little less than, the lawn is dense when running into, the sturdy situation of grass roots, there is the brush direct current generator to be difficult to overcome resistance and operate as normal also can be burnt motor sometimes.

Summary of the invention

The objective of the invention is to adopt brshless DC motor to replace having the brush direct current generator, give full play to the strong characteristics of the anti-stall ability of brshless DC motor, improve the effective utilization of electric lawn trimmer.

For achieving the above object, technical scheme of the present invention is, this electric lawn trimmer (three) formation includes, running gear, lifting regulating mechanism, motor, accumulator, power control switch, trimming tool, outer casing, it is characterized in that: it also includes electric machine controller in constituting, and described motor is a brshless DC motor, and accumulator is with electric machine controller and is electrically connected, and electric machine controller is with brshless DC motor and power control switch and is electrically connected.

In technique scheme, described brshless DC motor is made of rotor, stator, heat radiation fan blade, hall sensor, electric machine casing and fan housing, rotor is made of turning cylinder, iron core and magnet steel, iron core is fixed on the turning cylinder periphery, the magnet steel bar is fixed on outside the iron core equably, and the stator that has winding is fixed on the shell body, and hall sensor is fixed in the interior circular groove mouth of stator, the heat radiation wind wheel is fixed on turning cylinder one end, and fan housing is fixed on the electric machine casing termination and the wind wheel that will dispel the heat covers.

In technique scheme; described electric machine controller is by the battery tension sample circuit; the motor status signal sampling circuit; single chip machine controlling circuit; power-switching circuit; power on-off control circuit; the short circuit current holding circuit; the multiplex pulse modulation circuit; switch driving circuit constitutes; single chip machine controlling circuit is as core control part; single chip machine controlling circuit respectively with the battery tension sample circuit; the motor status signal sampling circuit; the short circuit current holding circuit; multiplex pulse modulation circuit and power on-off control circuit are connected; multiplex pulse modulation circuit output is connected with the switch driving circuit control end; the switch driving circuit power input is connected with accumulator output end; the switch driving circuit power output end is connected with the brshless DC motor power input; the input of power-switching circuit connects the output electrode of accumulator; the input of voltage sample circuit also is connected in the output electrode of accumulator; the power output end of power-switching circuit is connected to the power input of single chip machine controlling circuit and switch driving circuit respectively, and the hall sensor of motor status signal sampling circuit is fixed in the interior circular groove mouth of brushless DC motor stator.

Advantage of the present invention is, 1, the brushless DC motor structure that adopts simple, volume is little, in light weight, have ventilation, heat sinking function simultaneously, be with 1/2nd of power DC brush motor weight; 2, the spark potential safety hazard has been eliminated in the non-carbonate design of brshless DC motor, and long-term the use need not to change any parts, and motor run duration other electronic equipments to external world disturbs little; 3, electric machine controller has used the numerical control electronic switching circuit to drive and control brshless DC motor, and increased the short circuit current holding circuit, possessed under-voltage, current limliting and the stifled defencive function that carries, under-voltage, the current-limiting protection function can be protected battery overdischarge and heavy-current discharge effectively, current limliting, the stifled defencive function that carries can protect motor and controller to be burnt out effectively, reduced motor in complexity, the possibility that is damaged under the abominable environment for use, when having satisfied the turf-mown operation preferably, to the low rotation speed large torque requirement of motor, promoted the usefulness of lawn mower comprehensively; 4, use electronic switch to the motor control of turning round, high-efficient energy-saving environment friendly, and the directly fixing structural design of motor rotation axis and trimming tool, make motor and cutter keep working asynchronously, promptly open promptly and stop, do not have unloaded power consumption, ratio with more than the power motor economize on electricity 30-35%, and noise is low, heating is few, and it is sensitive and comfortable to prune Job Operations.5, technical solution of the present invention is applied widely, can replace following all the power grade brush direct current motors of 1000W.

Description of drawings

Fig. 1 is a final assembly schematic diagram of the present invention.

Fig. 2 is the structural representation (cutaway view) of brshless DC motor of the present invention.

Fig. 3 is the logic diagram of circuit of electric machine controller of the present invention.

In the above accompanying drawing, the 1st, trimming tool, the 2nd, roller; the 3rd, base, the 4th, battery mounting groove, the 5th, lifting joystick; the 6th, electric machine controller, the 7th, hand push steady hold-down screw, the 8th, accumulator; the 9th, hand push steady, the 10th, power switch, the 11st, brshless DC motor; the 12nd, motor fixed disk, the 13rd, motor shaft sleeve, the 14th, lifting control frame; the 15th, roller and base attaching parts, the 16th, outer casing, the 17th, fixed via; the 18th, socket fixture, 21 fan housings, the 22nd, heat radiation wind wheel; the 23rd, turning cylinder, the 24th, bearing, the 25th, stator winding; the 26th, magnet steel, the 27th, iron core, the 28th, bearing; the 29th, shell body, the 31st, accumulator, the 32nd, voltage sample circuit; the 33rd, power-switching circuit; the 34th, short-circuit protection circuit, the 35th, single chip machine controlling circuit, the 36th, power control circuit; the 37th, pulse modulated circuit; the 38th, motor status sample circuit, the 39th, switch driving circuit, the 40th, motor.

Embodiment

Embodiment one:

The overall structure of present embodiment and assembling are as shown in Figure 1.Four rolling 2 is connected with base 3 by attaching parts 15, lifting control frame 14 both was connected with attaching parts 15, be connected with lifting joystick 5 again, lifting joystick 5 is arranged at base 3 rears, hand push steady 9 is fixed on base 3 rear portions by hold-down screw 7, brshless DC motor 11 is fixed on above the base 3 by motor fixed disk 12, the turning cylinder of brshless DC motor 11 is fixing with trimming tool 1 by motor shaft sleeve 13 downwards, accumulator 8 is arranged in the motor rear and is fixed on battery mounting groove 4, electric machine controller 6 is positioned at motor the place ahead, and be fixed on above the base 3, socket fixture 18 is fixed on above the base 3, terminal box is fixedlyed connected with this socket fixture, this terminal box is electrically connected accumulator out-put supply line with the electric machine controller power input line, this terminal box also is electrically connected electric machine controller voltage sampling signal line with the battery feed line, this terminal box also is electrically connected electric machine controller out-put supply line with the brshless DC motor power input line, this terminal box also is electrically connected the motor status sampled signal line of electric machine controller with motor hall signal line, the lead-out wire that this terminal box also will be positioned at the power switch 10 on the hand push steady 9 is electrically connected with the electric machine controller power control line.

The present embodiment brushless DC motor structure as shown in Figure 2.Iron core 27 is fixed on turning cylinder 23 peripheries, and magnet steel 26 is fixed on iron core 27 peripheries equably, has stator winding 25 and is fixed on the shell body, and heat radiation wind wheel 22 is fixed on turning cylinder 23 1 ends, and fan housing 21 is fixed on motor housing body 29 terminations and the wind wheel that will dispel the heat covers.Hall sensor is fixed in the stator in the circular groove mouth, and when the magnet steel of opposed polarity on the rotor during over against hall sensor, hall sensor is promptly exported forward current or reversing the current.

Present embodiment electric machine controller circuit function block diagram as shown in Figure 3.Electric machine controller is constituted 39 and is constituted by battery tension sample circuit 32, power-switching circuit 33, short circuit current holding circuit 34, single chip machine controlling circuit 35, power on-off control circuit 36, multiplex pulse modulation circuit 37, motor status signal sampling circuit 38, switch driving circuit.Single chip machine controlling circuit 35 is as core control part; single chip machine controlling circuit 35 respectively with battery tension sample circuit 32; motor status signal sampling circuit 38; short circuit current holding circuit 34; multiplex pulse modulation circuit 37 and power on-off control circuit 36 are connected; multiplex pulse modulation circuit 37 outputs are connected with switch driving circuit 39 control ends; switch driving circuit 39 power inputs are connected with accumulator 31 outputs; the switch driving circuit power output end is connected with brshless DC motor 40 power inputs; the input of power-switching circuit 33 connects the output electrode of accumulator 31; the input of voltage sample circuit 32 also is connected in the output electrode of accumulator 31; the power output end of power-switching circuit 33 is connected to the power input of single chip machine controlling circuit 35 and switch driving circuit 39 respectively, and Hall element is fixed in the interior circular groove mouth of brushless DC motor stator in the motor status signal sampling circuit 38.

The present embodiment accumulator is 48V, power-switching circuit changes 48V into+and 5V is as the working power of single chip machine controlling circuit, simultaneously, power-switching circuit also changes 48V into+and 15V is as the working power of switch driving circuit, single chip machine controlling circuit obtains the battery tension value in real time from the battery tension sample circuit on the one hand, hall sensor from the motor status sample circuit obtains brushless DC motor stator and rotor relative position state on the other hand, single chip machine controlling circuit is under predefined program and parameter condition, the output of real-time monitoring multiplex pulse modulation circuit, and then multichannel device for power switching ON time separately in the control driving switch circuit, when the device for power switching conducting of certain road, accumulator+48V power supply just directly is loaded on certain stator winding of brshless DC motor, this stator winding generates an electromagnetic field and acts on epitrochanterian magnet steel, form rotating torque, make the rotor high-speed running.Draw manual this power control switch from power control circuit, this power switch is installed in and pushes away near the frame handrail, operates this power switch, just can control electronic switch action in the power control circuit.

The present embodiment brshless DC motor is 48V direct current supply; the design of electrical motor rotating speed is that per minute 3800 changes; the motor rated output power is 800W; owing to increased the short circuit current holding circuit in the electric machine controller; in conjunction with the software programming control of single chip machine controlling circuit, make motor have the short-circuit protection of startup, operation short-circuit protection, rotation-clogging protection, under-voltage protection simultaneously.

When pressing power control switch 10, motor begins to start, three hall sensors induce corresponding current potential, send single chip machine controlling circuit 35 to, single chip machine controlling circuit 35 is according to the sequential and the frequency that receive, judge the phase angle of motor, the control motor normally moves, single chip machine controlling circuit is according to the current signal and the hall signal that are sampled to, the simulated environment variable is converted to space vector, and then the motor stator electric current is divided into torque current and exciting current, making exciting current in this vector controlled is zero to guarantee to obtain with minimum current amplitude the output torque of maximum.Switch driving circuit 39 is six the tunnel, through six road independent amplifications, to obtain enough drive currents.

Claims

1. an electric lawn trimmer (three), its formation includes, running gear, lifting regulating mechanism, motor, accumulator, power control switch, trimming tool, outer casing, it is characterized in that: it also includes electric machine controller in constituting, and described motor is a brshless DC motor, accumulator is with electric machine controller and is electrically connected, and electric machine controller is with brshless DC motor and power control switch and is electrically connected.

2. electric lawn trimmer according to claim 1 (three), it is characterized in that: described brshless DC motor is made of rotor, stator, heat radiation fan blade, hall sensor, electric machine casing and fan housing, rotor is made of turning cylinder, iron core and magnet steel, iron core is fixed on the turning cylinder periphery, the magnet steel bar is fixed on outside the iron core equably, the stator that has winding is fixed on the shell body, hall sensor is fixed in the interior circular groove mouth of stator, the heat radiation wind wheel is fixed on turning cylinder one end, and fan housing is fixed on the electric machine casing termination and the wind wheel that will dispel the heat covers.

3. electric lawn trimmer according to claim 1 (three); it is characterized in that: described electric machine controller is by the battery tension sample circuit; the motor status signal sampling circuit; single chip machine controlling circuit; power-switching circuit; power on-off control circuit; the short circuit current holding circuit; the multiplex pulse modulation circuit; switch driving circuit constitutes; single chip machine controlling circuit is as core control part; single chip machine controlling circuit respectively with the battery tension sample circuit; the motor status signal sampling circuit; the short circuit current holding circuit; multiplex pulse modulation circuit and power on-off control circuit are connected; multiplex pulse modulation circuit output is connected with the switch driving circuit control end; the switch driving circuit power input is connected with accumulator output end; the switch driving circuit power output end is connected with the brshless DC motor power input; the input of power-switching circuit connects the output electrode of accumulator; the input of voltage sample circuit also is connected in the output electrode of accumulator; the power output end of power-switching circuit is connected to the power input of single chip machine controlling circuit and switch driving circuit respectively, and the hall sensor of motor status signal sampling circuit is fixed in the interior circular groove mouth of brushless DC motor stator.