US828983A

US828983A - Elevator-brake.

Info

Publication number: US828983A
Application number: US24061305A
Authority: US
Inventors: August Sundh
Original assignee: Otis Elevator Co
Current assignee: Otis Elevator Co
Priority date: 1905-01-11
Filing date: 1905-01-11
Publication date: 1906-08-21
Anticipated expiration: 1923-08-21

Description

No. 828,983. PATENTED AUG. 21; 1906.

A. SUNDH. ELEVATOR BRAKE.

APPLIGATION FILED JAN. 11, 1905.'

WITNESSES: j) S INVENTOR UNITED STA E PATENT orr AUGUST SUNDH, OF YONKERS, NIUV YORK. ASSIGNOR TO OTIS ELEVATOR COMPAN Y, OF JERSEY .(JITY. NEW JERSEY,

JERSEY.

A (JGR-PORATION OF NEW ELEVATQR-BRAKE.

Specification of Letters Patent.

Patented Aug. 21, 1906.

Application filed Ianuary 11. 1905- Serial No. 240,613.

elevators; and its object is to provide a com bination of certain elements by which the various forces which are enerated by the rotation of the motor and t e motion of an elevator may be used in bringing the elevator to rest.

In Patent N 0. 757,789, which was issued to me April 19, 1904, I have described an elevator-brake mechanism in which the rotary force of the motor is directly applied to the hoisting-drum ofan elevator through the setting of brake-shoes upon a friction-pulley which is attached to the rotary motor-armature shaft. a

The present invention is supplemental to that set forth in the above patent.

I will describe an elevator-brake made according to the present invention and point out the novel features thereof in claims.

Referring to the drawings, Figure 1 is a plan view of an electric elevator mechanism with my im roved brake attached thereto. Fig. 2 is an e ovation of a part of the apparatus shown in Fig. 1. In this case a part of the motor is cut away, and certain parts of the mechanism shown in section for the purpose of more clearly illustrating their construction and arrangements. Fig. 3 is an end elevation, partly in section, of a part of the mechanism shown in Fig.2, in this case illustrating more particularly the Windingdrum and a part of the improved mechanism which is applied thereto.

Fig. 4 is a Wiring diagram showing a method of connecting the various circuits used in an electric elevator in connection with the present invention.

Like characters of reference'designate corresponding parts in all of the fi ures.

1O designates the bed-plate 0 an elevator apparatus.

11 designates an electric motor which is bolted to the bed-plate and which furnishes the motive power for the apparatus. 12 is the armature of thismotor, and 13 14 are its brushes. The armature shaft 151s connected to a winding-drum 16 through intermedivate mecha11ism,\i'hicl1 in this particular case comprises Worm-gearing which is inclosed in a casing 17. This part of the apparatus is not shown morefully, because it constitutes no part of the present invention. ()n the armature-shaft is securely attached a frictionulley 20, to which brake-shoes 21 21 may. e applied by means of independentlymounted springs 23 23. These shoes may be arranged to be held away from the frictionpulley while the machine is running by means of an electromagnet 22, comprising two indeendent cores. The magnet 22 and the rake-shoes 21 21,with their connecting mechanism, which in this case comprises levers 24 24, pivoted at 25 25 and to the brake-shoes at 26 26, are all carried upon a yoke 30. It should benoted that the springs 23 23 and brake-shoes 21 21 are mounted and act independently, so that if-one shoe becomes inoperative the other may still be effective in operating the second brake, and thus stop the hoisting-drum as desired. The yoke 30 has bearings 31 31 on the armature-shaft on both sides of the friction-pulley 20. The yoke 30 is grooved on one side, as shown at 32, to re ceive a chain 33, which is securely attached to the yoke at 34. The chain is led downward and under two pulleys 35 35 on the un der side of the bed-plate 10, and its two ends are led from thence to a point 36, where they are joined to another chain 37. This chain asses around another pulley 38 and is led rom thence to and under a fourth pulley 39 and thence upward to a link 40, to which it is connected. The other end of this link is supported by a spring 41, which is attached to a fixed point 42 on a swinging horizontal bar 49. This spring 41 serves the purpose of keeping the, slack out of the chains 33*and 37 and of keeping the yoke 30 normally in the upright position in which it is shown in the drawings. (See Fig. 2.) The link is piv oted at 43 We lever 44, which is fulcrumed at 45 to the frameof the elevator apparatus. This lever 44 has two short arms 46 46, which by means of links 47 47 are connected to pivoted'levers 48 48, which are fulcrumed at 49 49. The other ends of the pivoted levers 48 48 are connected tobrake-shoes 50 50 at 51 51, which are adapted to engage with a surface on the inside of the winding-drum 16..

I will now point out the operation of so much of the apparatus as has just been described. VVhenever the current is cut H from the magnet 22, so that the brake-shoes 21 21 are applied to the friction-pulley 20 by the springs 23 28, they will, on account of their bearing upon the rotating friction-pulley, have a tendency to move with it. As the yoke 30, which holds them in position, is supported on the same shaft as the friction-pulley 20, the whole yoke 30 can move around the shaft with the friction-pulley. Its motion, however, is limited by the chains 38and 37 and their various connected parts. The motion which is imparted. to the yoke 30 in-the manner just described is transmitted through the

chains

33 and 37 to the lever 44 and through this lever and its mechanical connections to the brake-shoes 5O 50 in such direction as to force them against the inner surface of the winding-drum 16, so that not only will the brake-shoes 21 21 upon the frictine-pulley 20 have a tendency to stop the rotation of the motor because the movement of the yoke is limited, but also the brakeshoes 50, hearing on the inner surface of the winding-drum 16, will have a tendency to stop the rotation of the. drum and at the same time hold the drum from any ossible to-and-fro motion which it might liave as the apparatus comes to rest, and thusstop any up-a'nd-down vibration of the elevatorcar which may be connected to the windingdrum in the usual manner by means of cables. It will be noticed that as the rate of rotation of the motor-armature decreases the tendency of the friction-pulley 20 to turn the yoke 80 will become less and the pull on the

chains

33 and 37 will'become wealrer, so that the hralre shoes 50 50 will be eased off to some extent and the winding-drum 16- and the apparatus will come to an easy andgentle stop. This part of my invention has been already described in my Patent No. 757,789, already cited, as the apparatus which I have just described is but a simple modification of my former invention.

I will now describe the improvements which constitute the subject-matter of thepresent invention. The pivoted lever 44 in Fig. 3 isfcarried out to the left to a point 61, where it is attached to the plunger or core 62 'of'an electromagnet' 60. I will now point out the various circuits which are used in an electric elevator embodying my invention to show the way in which this electromagnet is used in connection with the apparatus already described. In doing this I will refer to Fig. 4. and designate Wires leadingfrom a source of electrical supply. The wire is connectedv to the upper terminals 73 73 of an electromagnetically-operated reversing-switch 70. This reversing-switch ging arms 71 72, each of 'lwo of each access are in electrical connection with each other and the third of each is insulated from t others. These three contacts on the swir ing arms 71 72 are adapted to make connections .with either of the two stationary contacts above them and to the wire to which they are connected or with two other static ary contacts 74 74 underneath the

swin arm

71 or 75 75 H i u. arm- 72;. One or the other of the swinging arms is always in contact with the lower con tacts. The wire 7 6 is connected to the positive wire and by means of a manually-operated switch 77 may be connected with either wire 78 or wire 79 of the magnets 71 or 72, respectively. The other terminals of these two magnets are connected by a wire 80 to the negative main. The

cores

81 and 82 of the magnets 71 and 72 are so arranged that when either of these magnets is energized it will draw its core upward and will cause the swinging arm to wlnch it is attached to make electrical connections with the stationary contact above it. For example, if the manually-operated switch 77 be moved to the left, on the wire 79 will be connected to the posi 've main, and so" the magnet 72 will receive current andbecome energized, so that it will raise its core 82 and cause the swinging arm 72, to which it is connected, to be moved up until it touches the stationary contact 73, which is above it. The motor-armature 12 is shown between and below the magnet-

cores

81 and 82. One of its brushes 13 is connected by suitable el trical conductors to the stationary ccnta 7 4 and 75, and its other brush 14 is simi connected to the stationary-

contacts

74 and 7 5 The two contacts which are connr together on each of the swinging arms o' reversing switch are connected by a conductor 83 to the upper terminal of the solenoid 3 1 and to the upper terminal of the magnet (30 and to the left-hand terminal of the shuut-- field 85 of the motor. tacts on the swinging arms are connected by a wire 86 to the lower terminal of the solenoid 8 1, the starting resistance 91,- and to the lower terminal of the magnet 60 through a resistance 87. This resistance 87 is some i 15 times made in the form of an extra field in the motor. The negative or Wire is connected by a wire 88 to a plate 89. A brush 99 connected to a core 84 of the solenoid 84. it is arranged to slide-over the plate 89 and over we contact-points to which the starting resistance 91 is connected. llt will be seen that the negative wire is thus connected to one of the terminals of the motor-armature 12 through the starting resistance 91, and one of the msulated contacts or the other is always in contact with the stationary contact under it. ithas already been pointed out that either the swinging arm 71 .orthe swinging arm 72 is al ways down the stationary contacts 1 0 The insulated conno from contact 73.

will be brought up against the stationarycontact 7 3 above it, and through it the wire '83 and the contact 74 will connect the posi-- tive wire to the brush 13 of the motor-armature. The solenoid 84 will. also be connected across the armature and will cause the starting resistance 91 to be cutout. The shuntfield 85 is also connected across the mains.

The brake-magnet 22 is connected, as shown,

. to the mains by means of the swinging arms 71 or 72. This apparatus and these circuits have been described but briefly, as they are well known in the art. By means of this apparatus the motor may be started in either direction at the will of the operator, and ifit is connected to an elevator in some such manner as that shown in Fig. 1 it will cause the elevator to travel up or down.

When the operator desires to stop the elevator, he will bring the manually-operated switch 77 back to its central position, thereby cutting off the current in the magnet 72 and so allowing the swinging arm 72 to dro away This will cut off t e current to the motor and to the brake-magnet 22, so that the motor will tend to stop rotating and the brake-shoes 21 21 will be applied to the friction-pulley 20, and the brake-shoes 5O 50 will be applied to the winding-drum 16. At the same time an armature short circuit will be established through the resistance or extra field 87 and the magnet 60. I will now trace this circuit. ,Starting with the brush 13, the circuit passes to the contact 7 4, thence through a part of the swinging arm 71 to the wire 83, which leads to the upper terminal of magnet 60. The other terminal of magnet 60 is connected to the resistance or extra field 87, and this is connected by wire 86 to the insulated contact of theswinging arm 71,which is now in electrical connection with the stationary contact 74, and this contact 7 4 is connected to the other brush 14 of the motor.

Thus it will beseen that as. long as the motor continues its rotationthecurrent which is generated thereby will pass through the magnet 60 and the resistance or extra field 87.'

to retard its rotation When the resistance 87 is made in the form of an extra field, the current which passes through it has a.tend ency to strengthen. the magnetic field of the motor, and that also has a tendenc to retard the rotation of its armature. T 6 current which passes through the magnet 60 will cause it to be energized, and as its core 62 is attached to the lever 44 at 61 the magnetic attraction of this magnet for its core will put an additional pressure upon the brake-shoes 5O 50. By the combination of the primary brake on the friction-pulley 60, the brakeshoes 50 50 on the windmg-drum 16, the electrodynamic effect of the armature short circuit, the strengthening of the fields by the current passing through the armature short circuit, and the extra pressure of the brakesho'es 50 50 due to the ull of the magnet 60 I have effected a brake or electric elevators in which the various forces which aregenerated by the rotation of the armature and the movement .of its connected parts are utilized for overcoming the momentum of the moving parts in bringing them to rest.

When the brake mechanism which is set forth in Patent 757,789 has been applied to an electric elevator in which the armature is short-circuited when being brought to rest, it

has been found that the retarding effect of this armature short circuit has minimized the effect which the primary brake on the fric- 'tion-plulley 20 has on the brake-shoes 50 50 on t e winding-drum. This is especially true when the elevator is carrying an extra mechanism and the car in substantially the same space of travel, regardless of the load or the speed of the elevator. This arrangement also brings the car to an easy and gentle stop, because as the motor slows down the current which it generates and which is passing through the magnet 60 will'become less until the ap aratus comes to rest.

Having escribed my invention, what I claim-is 1. The combination of a rotary member, a brake associated therewith and movable in :the direction of rotation of said member, a

second rotary member, a-brake associated therewith, means for moving said secondbrake into operative relation with said second. member by the. impressed movement of the first brake due to its frictional engagement with the first member, and electromagofthe-second'bralie.

' 2.- The combination of a rotary member, a brake associated therewith and movable in the direction at rotation of saidymember, a second rotary member, abrake associated neticmeans for increasing the braking effect .means for increasing the braking e'fiect of the second brake in proportion to therate of rotation of said rotary members.

3. The combination of a rotary shaft, a

friction-pulley thereon, a brake actingon the friction-pulley, a support for said brake con" structed to move around the shaft, and a second brake actuated by the impressed movement of said support\ due to frictional engagement of the first brake with the frictionpulley and electrical means for increasing the effect of said second brake.

4. The combination of an electric motor having an armature, two rotary members driven thereby, a device on each of said members for retarding the motion thereof, the sec- 0nd of said devices being brought into operation'by the first through the frictional enga'gement of the latter with one of the rotary members, and an electromagnet for increasing the effect of .the second retarding device, said magnet arranged to be connected across the motor-armature.

5. In an elevator, the combination of an electric motor having an armature, a hoisting-drum driven thereb a friction-pulley structed to act upon the drum and y connected to rotate wit the motor-armature, a brake constructed to retard the mo tionof said pulley and movable around the axis thereof, and a second brake constructed to act upon the drum and operated by the impressed movement of the iirst brake and by an electromagnet arranged to be con .nected across the motor-armature.

6; In an elevator mechanism, the combination of a motor, a hoisting-drum driven thereby, a friction-pulley connected to rotate with the motor, a brake constructed to retard the motion of the pulley and-,movable around the axis thereof, a second bra-he con 9 erated the impressed movement of the first brake, electromagnetic means for holding the first brake out of operative position during the normal running of the mechanism and electromagnetic means for increasing the effect of the second brake while the mechanism is being brought to rest.

7. In an elevator mechanism, the combination of an electric motor, a hoisting-drum driven by the motor, a retarding device on the drum actuated by the motion of the mo tor and by the current generated thereby.

8, in an elevator, the combination of an electric motor having an armature, an electrically-governed brake acting on the motor:

shaft, a hoisting-drum actuated by said shaft, a brake acting on said hoisting drum and me chanic'allyactuated by said first brake, an

electromagnet for increasing the effect of the ceases drum-brake, and means for conjointly cutting off currentfrom the motor, applying said first brake and connecting said magnet across the motor-armature.

9'. In an elevator,.the combination of an electric motor having an armature and a mag .netic field, a brakeacting on the motor-shaft, a hoisting-drum actuated by said shaft, a brake acting on the drum and mechanically operated by the shaft-brake, an electromagnet for increasin the effect of the drumbrake, an extra fie d-coil on the motor, means for cutting off current from the motor and connecting. the said electromagnet and the extra field-coil across the motor-armature.

10. In an electric elevator, the combination of an electric motorhaving an armature and a magnetic field, a mechanically-acting brake gripping a movable part of such elevaan electroresponsive device in the armature short circuit connected to the mechanical brake so as to give an additional braking effect proportionate to the speed of the armature.

12. The combination with abrakepulley,

of brake mechanism therefor,'movable supporting means for said brake mechanism, and separate devices for effecting the application of said brake mechanism.

13. The combination with amovable n1emher, of brake mechanism therefor and movable relatively thereto, and independent springs for effecting the application of said brake mechanism.

14. The combination with a single member, of brake mechanism therefor, movable supporting means for said brake mechanism, and independent devices for applying respective portions of said brake mechanism.

15. The combination with a rotating n1e1nber, of brake mechanism therefor, separate devices for operating said brake mechanism, and a movable support for said brake mechanism and said operating devices.

16; The combination with a brake-pulley, of a double brake therefor, independent de vices for applying the respective portions of said brake, a single mechanism for releasing said brake, and a support for said brake and mechanism, said support being movable rel atively to said brake-pulley.

17. The combination with a rotary member, of a brake associated therewith and movable in the direction of rotation of said meme ber, separate devices for effecting the application of said brake, a second rotary memloo brake-applying devices and the releasing ber, ,abrake associated therewith, and means, tuated by the im ressed motion of said first coacting with said'first-named brake for apbrake due to its i ictional contact with said plying said, second brake. 7 member. i i

18. Thecoinbination with a moving mem- In testimony whereof I have signed my 5- ber, of a brake associated therewith and movname inthe presence of two subscribing witr5 able in the direction of motion of said memnesses.

belt, independent springs for afiplying the re- 7 AUGUST SUNDH. spective portions of said bra e, an electro- Witnesses: magnet for releasing said brake against the W. H. BRADY,

10 action of said springs, and a second brake ac- ERNEST W. MARSHALL.