Elevator generally is to constitute like this: cage and bob-weight are to replace mode combined suspension up and down on sheave, and sheave links to each other with CD-ROM drive motor, and when motor stopped, sheave was braked and keeps this braking mode by brake equipment.In this type of elevator, between the weight owing to weight that comprises the cage in loading on and bob-weight certain weight difference is arranged, in the elevator start-up course, if brake equipment brake off and the torque of electro-motor remain zero, military order causes vibrations because of the overbalance of torque.Therefore, in a kind of method that is widely used for reducing this vibrations, adopted a kind of sensor that is used to measure the load of cage, make CD-ROM drive motor produce earlier one with the corresponding torque of torque differences after, just make the brake equipment brake off.
With regard to this method of controlling this type of motor torque according to the charge capacity that records, the method that we have known has:
1. first method provides torque instruction according to measured charge capacity to the torque control circuit of motor in the method, make the brake equipment brake off after having produced corresponding torque.
2. second method, the torque of CD-ROM drive motor is to change according to fixing ratio in the method, brake equipment then according to the corresponding time brake off of measured charge capacity (as a kind of example, but application reference number is 2275/1975 Japanese patent application).
Yet these methods must have a kind of mechanism of measuring elevator load, and this mechanism is adjusted needs the time.In addition, change, perhaps just in case the weight compensating between main wirerope and compensation wirerope is incomplete, then the torque differences that acts on the motor just can not obtain suitable compensation just in case in this load biography device, timeliness occurs.
Thereby, a kind of method that can save this type of load cell has been proposed, in the method, to just providing a gain that reduces the gain of Acceleration Control circuit to successively decrease circuit with the startup of control elevator (but Japanese patent application of this method application reference number 6278/1985) at the device of brake off.Yet, according to the method, because gain is controlled according to the unsettled condition of brake equipment, this just not only makes starting characteristic become unstable, and, also make elevator might begin to move once more, thereby cause the repetition of same operation cycle because acceleration/accel is under control.
Below in conjunction with accompanying drawing most preferred embodiment of the present invention is described:
Fig. 1 is a block scheme of representing according to a first embodiment of the invention mechanism that the startup of elevator is controlled.Reference symbol is represented respectively among the figure: [1] is power supply, and [2] are the power circuit of conv, and [3] are the power circuit of conv, [4] be reactor, [5] are CD-ROM drive motor, and [6] are current sensor, [7] and [11] be the basic driver circuit, [8] and [12] are pulse distributor, [9] are current control circuit, [10] be the summation point of current signal I and current feedback signal, [13] are the vector change-over circuit, and [14] are the vector calculus circuit, wherein f is a frequency instruction, Q is the phase bit instruction, and I is a current-order, I
tBe the torque current instruction, [15] are speed control circuit, and [16] are the summation point of speed command and actual speed; [17] be coder, [18] are sheave, and [19] are brake equipment, and [25] are the coil of brake equipment; [20] be jackstay, [21] are bob-weight, and [22] are cage, [23] for detecting the position transduser of the relative position between cage and the aspect, [24] be the displacement conv, [26] for being used to compensate the compensation wirerope of jackstay weight, [27] are speed command mechanism.
Therefore, if be used for the basic driver circuit [7] of conv, pulse distributor [8], current control circuit [9], the basic driver circuit [11] that is used for changer, pulse distributor [12], vector conv [13] or the like can be made into a single-chip micro controller system, just might control flexibly conv and changer.
Fig. 2 is the illustrative diagram of curves of a drive actions, and Fig. 2 (a) is the diagram of curves when not having the passenger, and Fig. 2 (b) is the diagram of curves of cage when carrying full passenger.T among Fig. 2
UBExpression is by the caused torque differences of weight difference between the weight of the weight of the cage that contains the passenger and bob-weight, T
BBe that the braking torque that unbalanced torque worked is poor, T
NBe the torque that CD-ROM drive motor produces, V
1Be the elevator speed that does not realize when of the present invention, V
2Be the elevator speed that has realized when of the present invention, V
PIt is speed command.
Fig. 3 has represented the characteristic curve of position transduser and position signal converter respectively.
Fig. 4 is the characteristic curve of explanation torque response, T
BBe the characteristic curve of the torque response of brake equipment, T
MIt is the characteristic curve of the torque response of motor.
Now, in conjunction with reference to figure 2(a) be not described in when having the passenger in the cage and how start.Because it is smaller to contain passenger's the weight of weight ratio bob-weight of cage of weight, this has just produced torque differences T
UBMeanwhile, the braking torque of brake equipment has produced-T
bAnd cage remained on quiescence.If, allow electric current flow to the coil of brake equipment in the moment of starting, then brake equipment begins to be disengaged braking, braking torque T
BThen descend and at time mark T
2Place's vanishing.Thereby, because braking torque T
BWith torque differences T
UBSynthetic torque T increases, and cage begins the speed V with elevator
1Quicken by direction upwards.That is to say, produce jumping phenomenon.On the contrary, if carry full passenger in the cage, shown in Fig. 2 (b), cage will be by instructing pointed opposite direction along speed V
1Curve quicken.That is to say that under any circumstance, elevator is after being quickened by synthetic torque T, elevator is subjected to according to time mark t
2The control of the speed command that the place provides.Thereby above-mentioned inverse transition phenomenon caused starting shock, thereby, make the passenger that uncomfortable feeling be arranged.
Therefore, according to the first embodiment of the present invention shown in Fig. 1, if design the output of position transduser to such an extent that can award speed summation point [16] through the displacement conv, that is to say, for example surpass as with reference to the aspect O on plane the time when the position of cage X moves up, the characteristic curve of position transduser as shown in Figure 3 just produces the negative signal (finger that is used to move down
Make).As Fig. 3 (b) and 3(c) when one of displacement conv [24] output during with signal that the distance of aspect O between the X of cage position is directly proportional, displacement conv [24] has produced the signal differential (being speed signal) of a position signal and has then produced second signal differential (being acceleration signal, signal wire (SW) b).In Fig. 3,1. reference number is the situation that the expression elevator increases with constant acceleration/accel, and 2. reference number is the situation that expression acceleration/accel itself is also increasing.
Thereby, if make electric current at time mark t
1The coil [25] of brake equipment, the torque T of brake equipment are flow through in the place
BBe reduced, cage will be by balancing moment T
UBTo move, but owing to contain position sensor [23]. the position loop of displacement conv [24] and speed summation point [16] has produced the torque T of motor
MThereby the effect brought into play makes this torque T
MWith brake equipment T
BSum becomes and torque differences T
UBEquate, even brake equipment [19] is at time mark T like this
1The place begins to be disengaged braking, and elevator is stopped under the situation that does not make the passenger feel to shake.
This is because the position item by position transduser [23] makes elevator aim at aspect and keeps motionless motor torque T
MSpeed faster speed in the time of can be than the cogging of brake equipment [19] produces.In addition, because make mobile the inhibition respond acceleration, thereby can further quicken above-mentioned action by differential value or second-order differential value.And as long as this control is made more effectively by Fig. 4 like that, as long as in a kind of like this convertor controls mechanism to motor torque T
MResponse ratio to braking torque T
BResponse fast about 1/10th, just order is because realization condition T promptly
UB=T
B+ T
MAnd obtain a very level and smooth drive performance.
In addition, because the position sensor [23] according to present embodiment can also be used as position transduser, this position transduser can reduce its speed and elevator and aspect be done to aim at again when stopping that thereby not needing be that some accessories increase extra-pays at elevator, and its manufacturing cost has also reduced with regard to corresponding.
Carry one in passing, in such an embodiment, the output of displacement conv [24] is at response time mark t
2Can successively decrease step by step after the speed signal at place, as the mode of coming load is compensated by detected load formerly.
Fig. 5 is according to second embodiment of the present invention, adopts therefore being described it no longer of identical reference symbol for part same as the previously described embodiments.Present embodiment is characterised in that on the summation point of speed command and actual speed of through displacement conv [28] output of speed sensor [17] being added under the situation that does not adopt position transduser.Displacement conv [28] is quadratured from the displacement that the commentaries on classics amount detects elevator of executing of rotating object to speed sensor [17] signal.Thereby, if with displacement change pick out device [28] make have with Fig. 3 in the identical characteristic curve of cage position transduser, elevator will be operated according to the foregoing description, promptly the position of cage can overlap with aspect, so just can stop torque differences T
UBCause moving of cage, thereby also just can obtain level and smooth driving feature in situation without any vibrations.
In addition, above-mentioned displacement conv [28] also can be made a kind of structure that does not rely on aspect, and only the signal of speed sensor [17] is quadratured so that the displacement when only starting.In this case, because can obtain displacement,, promptly be that the position that elevator never overlaps with aspect starts the position of the cage before starting, also can proceed from reality produces suitable compensation torque T
M
Fig. 6 represents the 3rd embodiment, and the feature of this embodiment is that the signal of position transduser [23] offers speed device [16] through displacement conv [29].The signal of position transduser [23] provides torque summation point [32] through acceleration/accel conv [30] on the other hand.
Thereby the output signal of displacement conv [29] has produced position signal and signal differential thereof, i.e. speed signal as shown in Figure 3 is so that the effect that position signal is played the cage position is overlapped with aspect.
The generation of this acceleration/accel conv [30] a kind of acceleration signal, this is to derive out from the position signal of second derivative, and this signal is offered the torque summation point [32] of torque instruction electric current, this electric current is the outgoing current of speed control circuit [15].Thereby, since can make the braking of the displacement of cage by this acceleration/accel loop faster, so also just can obtain level and smooth starting characteristic.
Fig. 7 represents the 4th embodiment, and in this embodiment, position signal that is obtained in Fig. 6 or similar signal obtain from speed sensor [17].
A kind of acceleration feedback loop is provided among this embodiment, this loop is applied to the signal of speed sensor [17] on the speed summation point [16] through the displacement conv [28] of the rotation amount of acquisition swivel, and the aspect is applied to the signal of speed sensor [17] on the acceleration/accel summation point [32] through acceleration/accel conv [31] in addition.By displacement conv [28], this loop is used for position X to elevator and brakes and keep this position, so that make cage aim at aspect.Because this acceleration/accel promptly captures above-mentioned motion and this motion is stopped through acceleration/accel conv [31], just can obtain level and smooth starting characteristic without any vibrations.
Various embodiment have been described hereinbefore.Yet, in above-mentioned any embodiment, owing to do not adopt the expensive load cell of the price eighteenth of the twenty, the startup of elevator is become smoothly, but also avoided variation because of the aging caused starting characteristic of load cell.Thereby make maintenance, the cross-check sum investigation also just becomes unnecessary.
In addition, because load cell normally adopts proof rubber or spring leaf etc. to be installed, thereby the load that support elevator framework is born is a concentrated load.Like this, because must use can bear the mechanism of this load, so the weight of elevator framework etc. just has the trend that becomes bigger.Yet, according to the present invention, because that load cell becomes is unnecessary, so not only the weight of member and cage can reduce, the size of motor and the size of control mechanism can be made lessly, and electric peak power by elevator consumption is diminished and make consumption of power also become less.
In addition because compensating torque is to be produced by the torque balance of motor, so even the weight of jackstay [20] also can compensate by compensation wirerope [26] fully, thereby in order to acquisition without any the level and smooth starting characteristic that shakes.Thereby, can reduce the number that compensates wirerope, this just can make both economical mechanism.