Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
  • B66B1/00—Control systems of elevators in general
  • B66B1/24—Control systems with regulation, i.e. with retroactive action, for influencing travelling speed, acceleration, or deceleration
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
  • B66B1/00—Control systems of elevators in general
  • B66B1/34—Details, e.g. call counting devices, data transmission from car to control system, devices giving information to the control system
  • B66B1/36—Means for stopping the cars, cages, or skips at predetermined levels
  • B66B1/40—Means for stopping the cars, cages, or skips at predetermined levels and for correct levelling at landings
  • B66B1/405—Means for stopping the cars, cages, or skips at predetermined levels and for correct levelling at landings for hydraulically actuated elevators

Definitions

• the present invention relates to an electrically controlled valve apparatus provided with an inlet conduit for the pressurized fluid, with an outlet conduit for a tank or equivalent in order to drain the fluid from the valve, and with an outlet conduit for an actuator proper, such as a cylinder .
• the SE publication of application 367 172 introduces a solution which aims at employing two magnetic valves.
• the said aim is achieved, but as regards hydraulics, the result is an extremely complex valve assembly composed of magnetic valves of the simple on-off type, which either close the respective flow path, or the flow path remains completelyopen .
• the valve construction introduced in the DE publication of application 1 268 801 fulfils the above mentioned requirements set forth for modern technique, but does so by means of hydraulic arrangements even more complicated than in the said SE publication.
• the apparatus comprises two magnetic valves of the on-off type, two operating spindles, a precision spindle as well as two throttle valves and a current distributor valve. The latteris needed for driving independent of the load.
• the third example is the US patent publication 4 418 794.
• the valve introduced in this publication comprises three operating spindles, one of which is employed steplessly by means of an electric motor, a screw sleeve and a screw bar, as well as an on-off type magnetic valve and one pressure-controlled directional valve. Consequently, this valve arrangement is fairly complex, too, mainly owing to the large number of components of different types.
• the purpose of the present invention is to eliminate the above mentioned drawbacks, among others, and to realize a valve apparatus which is simple in structure and reliable in operation. This is achieved by means of the characteristic novel features of the invention, presented in the appended patent claims.
• the apparatus of the invention comprises a chamber or
• the apparatus comprises two throttle valves for constricting the conduits between the back spaces of the operating spindles and the fluid tank;an
• the throttle valves are adjusted, through their respective actuators, so that the position of the operating spindles, and the hydraulic flows in the openings, which are regulated by the said spindles, are such that the lift cage, the hoist platform or the like
• the controlling of the operating spindles of the valve apparatus is carried out by means of one single combined throttle valve instead
• the sensors are used for measuring the volume flow of the hydraulic fluid, i.e. the length of the axial movement of the operating spindle, which indirectly means the velocity of the lift cage or equivalent, whereas in the second embodiment the velocity of the lift cage is measured directly by means of a suitable impulse sensor.
• the information received from the sensor is processed in the control unit and utilized for controlling the throttle valve or valves, by aid of which throttle valves, and through two operating valves, there is adjusted the volume of the hydraulic flow from the pump into the cylinder of the lift cage or of the hoist device and into the tank, as well as from the cylinder into the tank.
• valve apparatus of the present invention Several advantages are achieved by employing the valve apparatus of the present invention, particularly if the invention is applied for regulating the operation of hydraulic elevators.
• the lift cage can be stopped exactly at the correct floor landing.
• the creeping distance and velocity follow the given measures accurately. Changes in the load do not affect the said measures. Variations in the temperature of the hydraulic fluid, and the resulting variations in the volume, do not cause erroneous functions and/or creeping; the position of the lift cage is automatically corrected.
• Inside the lift cage there can be arranged an alarm button whereby the cage can be made to descend to a desired lower floor. It is pointed out that a similar arrangement is not commercially available for hydraulic elevators at the moment, but in alarm cases the lift cage must be descended from the engine room.
• valve apparatus proper is simple in structure; the number of separate hydraulic elements has fallen to about half of what is normally used. With respect to the size of the valve apparatus, the treated volume of hydraulic fluid is at least doubled in comparison with ordinary valve apparatuses of the corresponding size.
• Figure 1 shows in partial cross-section a valve apparatus of the invention, applied to a hydraulic elevator
• Figure 2 is a diagram of the lift cage velocity achieved by employing the said valve apparatus
• Figure 3A is an illustration of another valve apparatus of the invention, likewise applied to an elevator
• Figure 3B illustrates the wobbler attached to the stepping motor, seen from the top
• Figure 4 is a block diagram of a control unit which is suited for controlling the valve apparatus of the invention .
• the valve apparatus comprises the valve housing 1, which is provided with an inlet conduit or opening 2, seen from the entering direction of the hydraulic fluid, through which opening the fluid pressurized by " the pump P enters the valve apparatus from the tank T.
• the inlet conduit 2 is provided with a countervalve 3 and strings 4. After passing this, the pressure fluid enters the first chamber 5.
• the two operating spindles 6 and 7, advantageously charged by the strings 8 and 9, are pressed in the chamber 5.
• a return conduit 12 is opened for the fluid through the first opening 10 directly back into the tank T.
• the operating spindle 6 comprises a shaft 13 or equivalent which protrudes from the valve housing 1.
• a shaft 14 or bracket protrudes from the valve housing 1, the said shaft being provided with the sensors 15 and 16 attached thereto, which sensors react to the movement of the shaft 13 and thus to the movement of the operating spindle 6 by sending respective impulses to the control unit 17.
• a conduit 25 leads to the throttle valve 26, which is electrically controlled.
• the spindle 27 of the throttle valve 26 is advantageously conical in shape. By employing this valve, it is possible to regulate the flow taking place through the opening 28, from the chamber 24 via the conduit 25 into the conduit 29 which leads into the fluid tank T.
• the chamber 24 is connected to the inlet conduit 2 by means of a conduit 30.
• the second operating spindle 7 functions in a similar fashion as the first operating spindle 6.
• the hydraulic fluid has access through the second opening 18, into the outlet conduit 19, which leads onto the cylinder S serving as the actuator of the elevator HS or the like.
• the spindle 7 also comprises a shaft 20 or equivalent, and a shaft 21 or bracket protruding from the valve housing, the said shaft 21 being provided with sensors 22 and 23 attached thereto, which sensors send impulses to the control unit 17 in accordance with the movements of the spindle 7.
• the conduit 33 via the countervalve 34 to the second throttle valve 35, which is likewise electrically controlled.
• the spindle 36 pertaining to this valve 35 which spindle is advantage- ously provided with a conical collar 36a, it is possible to close the conduit or the opening 37 on the opposite side of the countervalve 34.
• the spindle 36 has a pin-like head 36b, which is used for opening the countervalve 34 in the conduit 37 before the collar 36a of the spindle 36 closes the flow path, i.e. the conduit 37.
• the conduit 38 leads from the throttle valve 35 directly into the fluid tank T.
• the valve apparatus of the invention is connected to a hydraulic elevator, the actuator whereof is the cylinder S.
• the lift cage HS is in an exemplary fashion arranged to move between the landing Kl of the first floor and the landing K2 of the second floor.
• buttons KP1 and KP2 On both floors there are arranged call buttons KP1 and KP2, .and the lift cage is provided with respective floor buttons PI and P2 as well as with an alarm button HP. All buttons are connected to the control unit 17.
• the operation of the valve apparatus of the invention is below explained with reference to the velocity diagram of the elevator, illustrated in Figure 2.
• the initial position confirms to the situation illustrated in figure 1 and is marked by point A in figure 2.
• the elevator HS is on the first floor Kl, and the floor button P2 or the call button KP2 of the elevator has been pressed, i.e. it is desired KP2 of the elevator has been pressed, i.e. it is desired that the elevator rises to the second floor.
• the message is registered in the control unit 17. Through the control unit 17, the pump P is started, advantageously first with a small efficiency only.
• the countervalve 3 is opened due to the hydraulic pressure, and the hydraulic pressure formed in the chamber 5 shifts the first operating spindle 6 to the left and thus allows the fluid flow to enter, via the conduit 12, back into the tank T.
• the fluid located in the chamber 24 behind the spindle 6 is pressed into the conduit 25, pushes the spindle 27 open and flows along the conduit 29 back into the tank T.
• the control unit 17 has simultaneously switched a control voltage to the electrically controlled throttle valve 26 and started to observe the sensors 22 and 23. All this time the hydraulic .fluid has flown along the conduit 30 from the inlet conduit 2 into the chamber 24 and further along the conduits 25 and 29 back into the tank T.
• the lift cage HS is now .driven with constant speed to the desired floor, in this case the second floor - the interval B-C in Figure 2.
• the voltage of the throttle valve 26 remains constant, in which case the operating spindles 6 and 7 also stay in position.
• an impulse is sent to the control unit 17 by means of the floor approach signal L2 or equivalent and the sensor AH, whereafter the control unit starts evenly reducing the control voltage onto the throttle valve 26.
• the operating spindle 6 moves slowly to the left, away from the seat, while the spindle 27 of the throttle valve 26 keeps opening the opening 28 and the conduit 25, which causes a constantly growing amount of the hydraulic flow from the pump P to be conducted diretly into the tank T via the chamber 5, the opening 10 and the conduit 12.
• the reduction of the control voltage in the throttle valve 35 is started in an even fashion, in which case the spindle 36 starts to move inwards and the conical collar 36a starts to open the conduit 37.
• the pressure fluid is discharged from the chamber 31 via the conduits 33 and 38 into the tank T. Because the cross-sectional area of the conduit 32 is smaller than that of the conduit 33, the pressure in the chamber 31 is reduced and the second operating spindle 7 is free to rise from its seat, thus allowing the fluid to flow from the cylinder 5 via the conduit 19 and the opening 18 into the chamber 5. From this chamber, the fluid is discharged into the tank T by pushing the first spindle 6 against its spring 3 to the left, so that the opening 10 and the conduit 12 are opened.
• the head of the shaft 13 has also settled beside the sensor 16. Now the sensor 16 sends an impulse to the control unit 17, which stops the increasing of the control pressure on the throttle valve 35.
• the lift cage moves at an even creeping speed during the interval I-K in Figure 2.
• the valve apparatus of the invention is in principle formed of two electro-hydraulic circuits, which comprise the first, electrically controlled throttle valve 26, the conduits 25 and 29, as well as the sensors 22 and 23, and the second electrically controlled throttle valve 35, the conduits 33 and 38 and the sensors 15 and 16.
• the first operating spindle 6 and the second operating spindle 7 are employed in different tasks, depending on the motional direction of the elevator.
• the countervalve 34 is used for stopping the lift cage at a determined height.
• the spindle 36 of the throttle valve 35 is pulled in and the spindle 27 of the throttle valve 26 is pushed out.
• the sensors 15, 16, 22 and 23 can be for example magnetic or photoelectric sensors, or other corresponding sensors of a conventional, tried and acknowledged type.
• the heads of the shafts 13 and 20 or the members attached to the shafts can form an actively functioning pair together with a sensor, or they can for instance only obstruct a ray of light which passes from the light emitting diode (LED) of the sensor into the phototransistor or equivalent light detector.
• LED light emitting diode
• the sensors are located on protruding shafts or corresponding members, the limiting values of the lift cage motional velocity are easily changed by shifting the sensors.
• FIG. 3 A introduces another valve apparatus of the invention.
• the valve apparatus comprises the valve housing 1 provided with an inlet conduit 2 seen in the entering direction of the fluid; through this inlet conduit 2 the fluid pumped from the tank T by the pump P enters the valve apparatus.
• the inlet conduit 2 is provided with the countervalve 3 and string 4. After passing this, the hydraulic fluid is conducted into the chamber 5 where its pressure is urged towards two operating spindles, the first spindle 6 and the second spindle 7, both being provided with strings 8 and 9 on their opposite sides.
• the second operating spindle 7 is formed of two matched spindle elements 7a and 7b. Between these, the first spindle element 7a covers the large openig 11 of the seat, and the second 7b covers the small opening 39, which is arranged in the middle of the first spindle. Behind the operating spindle 7 there is located the chamber 31, whereinto the conduit 32 leads from the actuator connection, i.e. from the conduit 19. Also from the chamber 31, the conduit 40 leads out via tahe countervalve 41 onto the throttle valve 42.
• the countervalve 41 and the throttle valve 42 are placed in the same valve duct 44, advantageously within a uniform housing 43.
• the middle part 44b of the valve duct 44 is smaller in cross-section than either of its end parts 44a and 44c.
• the countervalve 41 In the second closed end part 44c of the valve duct 44 there is installed the countervalve 41, the string 41a and a closure member such as the ball 41b.
• the ball 41b rests, under the pressure of the string 41a, against the middle part 44b of the valve duct 44, so that it closes the valve duct 44.
• the conduit 45 leads from the other side of the countervalve 41, i.e. from the side opposite to the conduit 40, directly into the tank T or alternatively into the chamber 5 (the dotted line in Figure 3).
• the ball 41b of the countervalve 41 both prevents and regulates the flow taking place from the conduit 40 via the valve duct 44 into the conduit 45 and the tank T.
• the spindle 46 of the throttle valve 42 is a bar-like member, the first end 47 whereof is pin-like. After this end 47 comes the extension 48, the conical collar 49, the middle part 50 and "the other end 51.
• the extension 48 is fitted within the middle part 44b of the valve duct 44 so that it prevents all flowing between the conduits 45 and 52.
• the conical collar 49 of the spindle 46, and the middle part 44b of the valve duct serve as the throttle valve 42 proper between the conduits 52 and 53.
• the conduit 53 leads into the fluid tank T.
• the conduit 52 leads onto the throttle valve 42, and by employing the collar 49 of the spindle 46 of the said valve 42 it is possible to regulate the flow from the space 24 via the conduit 52 into the conduit 53 and further into the fluid tank T.
• the space 24 is coupled to the pump connection, i.e. to the inlet conduit 2, by means of the conduit 54.
• the shifting device of the spindle 46 of the throttle valve 42 is the stepping motor 55 with the wobbler 56 attached to its axis, or an equivalent control member.
• the outlet conduit 19 of the valve apparatus is connected to the employed actuator proper such as the hydraulic cylinder S, whereby the lift cage HS, the hoist platform or the like can be lifted from a landing or floor to another and descended in the like manner .
• the velocity and position of the lift cage HS is observed by means of the impulse sensor 58.
• the impulse sensor 58 At the top and the bottom of the lift well there are arranged runner wheels 59, 60 or equivalent members, over which the wire cable 61 is arranged to slide.
• the wire cable 61 is attached to the lift cage HS.
• the wire cable 61 runs through the impulse sensor 5 J 8.
• the -impulse sensor 58 comprises the round disc 58a, which is rotated by the wire cable 61 moving along with the lift cage. The rotating of the disc is measured for instance electrooptically, and the information is fed into the control unit 57.
• the lift cage and the separate floors are provided with similar floor and approach signals as in the embodiment of Figure 1.
• This home position is detected for instance by aid of microswitch 62 placed on the opposite side of the wobbler. In this case there can be even an interval between the spindle 46 and t_)_ wobbler 56.
• the spindle 46 is pressed against the edge of the wobbler when the pressure in the chamber 5 is increased.
• the stepping of the motor 55 is begun under the control of the control unit 57, and the wobbler 56 starts to turn and to push the spindle into the direction B.
• the conical collar 49 starts closing the opening between the conduits 52 and 53.
• the hydraulic pressure in increasing and pushing the spindle 6 towards the seat and the chamber 5. It closes the opening 10 and the conduit 12 into the tank T. Pressure in the chamber 5 increases.
• the operating spindle 7. (whole of the spindle 7a) is opened, and the fluid has access into the cylinder S via the conduit 19. It is si ultaneuously observed, by aid of the control unit 57, whether the lift cage has taken off.
• the first motion impulse of the lift cage HS is received from the impulse sensor 58.
• the acceleration of the lift cage is started. If the first motion impulses come in succession in a series quicker than should be allowed, the stepping motor 55 is stepped backwards, so that the spindle 46 moves into the direction A, i.e. the flow from the conduit 52 into the conduit 53 is increased, and the pressure within the chamber 24 is reduced, and the conduit 12 is slightly opened.
• the approach signal L2 sends a message in order to start the slow-down - point C in Figure 2.
• the spindle 46 is shifted into the direction A by employing the stepping motor 55 and the wobbler 56 (or the hydraulic pressure), so that the opening between the collar 49 and the ventilation duct 44b is increased between the conduits 52 and 53, and simultaneously the fluid flow from the chamber 24 into the tank T is increased and the operating spindle 7 closes part of the opening 11 between the chamber 5 and the outlet conduit 19.
• This procedure is continued " , until the speed of the lift cage reaches a certain limit, i.e. the point D in Figure 2, wherefrom the lift cage is driven forward at the constant creeping speed, until a message is received from the floor signal KL2.
• the floor information is received with the accuracy of +1 mm.
• the floor information is obstained for example from the lift well, from the edge of the 100 mm wide floor signal KL1, KL2 in the motional direction of the lift cage.
• the lift cage is stopped by aid of the control unit 57 at 50 mm from the edge of the said signal, whereafter the pump P is stopped.
• the timing of the downward drive corresponds to the beginning of the upward drive described above; the pump P is not started, however.
• the stepping motor 55 and the wobbler 56 are again in home position (figure 3 B).
• the spindle 46 is pushed sufficiently in the direction B by aid of the stepping motor 55 and the wobbler 56, so that the countervalve 41 is opened by means of the pin 47; the hydraulic fluid from the back chamber 31 of the second operating spindle 7 starts to flow into the tank T via the conduit 40, the countervalve 41 and the conduit 45.
• the acceleration of the lift cage HS, F-G in Figure 2 is adjusted to be constant by aid of the control unit 57 again on the basis of the impulses received from the impulse sensor 58, so that it remains suitable until the desired descending speed G of the lift cage is achieved ( Figure 2).
• the inner spindle 7b By employing the inner spindle 7b, an excellent controllability of the system is achieved; the takeoff downwards is carried out softly. If the countervalve 41 for some reason is closed (error of the control unit, the stepping motor breaks down etc.), the pressure in the chamber 31 increases, and the inner spindle 7b begins to close against the seat. However, this takes place in a controlled manner, because there is fluid in between the inner and the outer spindles 7a, 7b, and this fluid can flow out both through the opening between the piston 7c of the inner spindle 7b and the wall of the chamber 31, and through the opening between the upper end of the outer spindle 7a and the wall of the chamber 31, both into the chamber 31 and into the outlet conduit 19. Now the lift cage HS stops softly. It is pointed out that while driving upwards, the spindles 7a and 7b function as one uniform entity.
• the conduit 45 is advantageously connected to the chamber 5.
• the purpose of this arrangement is to prevent the descending speed of the lift cage HS from growing too fast in case the countervalve 41 should leak or be broken. In that case the hydraulic pressure is now evened out over the operating spindle 7 via the conduits 40 and 45 into the chamber 31.
• valve apparatus of the invention By employing the valve apparatus of the invention, it is easy to correct the changes and slide-downs that in the course of time take place in the position of the lift cage with respect to the floor landings, which changes are due to the changes in the temperature, and corisequently in the volume of the fluid.
• the 'impulse sensor 58 by aid of the control unit 57, controls the position of the lift cage with an accuracy of for instance +1 mm.
• the control unit starts the pump P, and the lift cage HS is lifted back into its proper position.
• the control unit 57 In case the lift cage HS should, for one reason or another, stop in the middle of the drive, the control unit 57 returns the stepping motor 55 and the wobbler 56 attached thereto into home position.
• the general procedure in the case of faults is to return the stepping motor 55 and the wobbler into home position.
• the stepping motor controlled by the control unit 57, winds the wobbler 56 into such a predetermined position where the countervalve 41 is opened, under the pressure of the pin-like head 47 of the spindle 46, so much that the hydraulic pressure in the chamber 31 starts to decrease, but not so much as to lift the inner spindle 7b apart from the outer spindle 7a.
• the countervalve 41 is closed and its spring presses the spindle 46 into the direction A, so that the released wobbler 56 is wound to home position, and simultanously the lift cage HS is stopped.
• the control unit 57 (as well as 17) comprises advantage ⁇ ously and according to Figure 4: the data processing unit proper, such as the microprocessor 63; the read only memory ROM 64, where the permanent operating system is stored; the random access memory RAM 65, where the variables and for instance the specific information of each elevator is stored; the timers T 66 for synchronizing the various circuits; an UART circuit 67, whereby the control unit 57 can be connected for instance to ' e-xternal computers; the inlet circuits 68 and the opto-couplers 69 connected thereto, via which couplers the messages from the call buttons, the floor buttons, the approach and floor signals etc.
• the data processing unit proper such as the microprocessor 63
• the read only memory ROM 64 where the permanent operating system is stored
• the random access memory RAM 65 where the variables and for instance the specific information of each elevator is stored
• the timers T 66 for synchronizing the various circuits
• an UART circuit 67 whereby the control unit 57 can be connected
• the outlet circuits 70 and the control circuits connected thereto for operating the actuator of the throttle valve 42, i.e. the stepping motor 55, for switching the pump P on and off and for giving external alarms etc. and, in addition to this, for example for supervising the control systems of the control circuits 72.
• valve apparatus itself does not necessarily have to resemble the embodiment presented in Figure 1 or 3, because the conduits and the separate, valves can be arranged in many different ways, and their arrangement is mainly dictated by the requirements of the specific application in question, as well as by the manufacturing technique.
• conduits and the separate, valves can be arranged in many different ways, and their arrangement is mainly dictated by the requirements of the specific application in question, as well as by the manufacturing technique.

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• Engineering & Computer Science (AREA)
• Automation & Control Theory (AREA)
• Computer Networks & Wireless Communication (AREA)
• Fluid-Pressure Circuits (AREA)
• Elevator Control (AREA)
• Types And Forms Of Lifts (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (1)

Family

ID=8520750

Family Applications (1)

Country Status (7)

Cited By (5)

Families Citing this family (7)

Citations (4)

Family Cites Families (1)

• 1985
  • 1985-04-30 FI FI851721A patent/FI71710C/fi not_active IP Right Cessation
• 1986
  • 1986-04-30 WO PCT/FI1986/000043 patent/WO1986006359A1/en active IP Right Grant
  • 1986-04-30 JP JP61502739A patent/JPS62502767A/ja active Pending
  • 1986-04-30 EP EP86902836A patent/EP0222801B1/en not_active Expired
  • 1986-04-30 DE DE8686902836T patent/DE3664453D1/de not_active Expired
  • 1986-04-30 US US07/010,131 patent/US4757879A/en not_active Expired - Fee Related
  • 1986-11-21 DK DK560786A patent/DK154635C/da not_active IP Right Cessation

Patent Citations (4)

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