US1108084A - Block system for tramways. - Google Patents

Description

D. D. SAMAIA. BLOCK SYSTEM FOR TRAMWAYS.

APPLIUATION FILED SEPT. 29, m1.

1, 1 08,084. Patented Aug. 18, 1914,

2 SHEETS-SHEET l.

D. D.v SAMAIA. BLOCK SYSTEM FOR TRAMWAYS. APPLIOATION FILED SEPT. 29, 1911.

1,108,084. Patented Aug. 18, 1914.

niet .vo/ams PEIERS cu v IHom L/THU '.vArmlNbmN. 11 1 DINO DAVIDE SAMAIA, OF MILAN, ITALY.

BLOCK SYSTEM FOR TRAMWAYS.

Specification of Letters Patent.

Patented Aug. 18, 1914.

Application ledseptember 29, 1911. Serial No. 651,950.

To all LU/Lomi t may concern.'

Be it known that I, DINO DAVIDE SAMAIA, a subject of the King of Italy. residing at 11 Via Caradosso, Milan, Italy, have invented a certain new and useful Block System for Tramways, of which the following is a specification.

The present invention has for its object a block system for tramway lines which is of'very simple construction, and which assures great security in operation. Y

The principal characteristics of this system are 1. That a certain number of cars having entered the single track an equal number must leave before the semaphore will give the signal for line clear. 2. That in the case where two cars following each other on the same line arrive at the same instant, one at the point of entry on the single track and the other at the point at which the single track is left the working remains suspended, the semaphore remaining in the position which indicates that the line is blocked, and which is determined by the'passage of the first car. 3. That when a car has by mistake passed on to the single track and must be drawn back on to the double track the semaphores will be brought back into the same position as they were before the car moved on to the single track.

In the accompanying drawing. which represents a constructional form of the invention; Figure 1 is a view of the general arrangement. Fig. 2 shows the device for taking current from overhead. Fig. 3 isa front elevation of the signaling device and Fig. 4 is a side view of the same arrangement.

As will be seen from Fig. 1, the system comprises four devices for taking current, 1, 2, 3, 4, (two for cars passing in one direction, and two for cars passing in the other direction,) provided on the trolley wire: two semaphores 5 and 6 which may be fixed to the wall or better, suspended in the middle of the track.

. Each device for taking current (Fig. 2) is constituted by a movable yoke or frame 8 through which passes the trolley wire 9. This yoke is hinged to levers 10, 10 which are pivoted at 11, 11 to the cover 12. At the point at which they are pivoted to the yoke 8, the levers 10, 10 are provided with projections 13, 13'.. Rods 14 14 are so providedas to be capable of slidingin the oilinterrupters 15, 15. Each of these interrupters (see the part in section in Fig. 2) comprises copper blades 16, connected at their upper ends to the rod of the interrupter, and the lower extremities of which dip into the oil. The spring 17 normally presses the rod 14 downward so as to break the contact of the blades 16 with the metallic walls of the interrupter.

The signaling device (Figs. 3 and 4) cornprises essentially a screwed shaft 18, provided with a longitudinal groove 19, this shaft passing through wheels 20, 21, which are mounted on the double support 22. The hub ofthe wheel 20 is provided in the interior with a nut adapted to gear with the threads of the shaft 18, while in the interior of the hub of the wheel 21 is fixed a key which can slide along 'the groove 19 of the shaft 18.

Thevwheels 20, 21 each carry four pins which during the operation of the device are engaged by toothed levers 23, 24, which are connected respectively to the rods of the solenoids 25, 26.

The signaling disk 27 is carried by a shaft 28 which is normally held in such a position by a spring 32 that the disk 27 indicates that the line is blocked. To the upper extremity of the shaft 28 is keyed a crank 29. `This crank 29 is in its turn connected to a lever 30 connected to one arm of a bell crank lever 31, pivotally suspended at 31, the other arm of said bell crank lever being in contact with the end of the screwed shaft 18.

The circuits from the separate devices 1, 2 3 and 4 for taking current to the semaphores 5 and 6 are as follows: The circuits of the device 1 consists of the terminal 15, the conductor 1", the magnet 25 of the semaphore 6, y

and the magnet to earth; the terminal 151, the conductor 1* the magnet 26 of the semaphore 6, and the magnet to earth. The circuits of the device 2 consist of the terminal 151, the conductor 2b, the magnet 26 of the semaphore 6, and themagnet to earth; the terminal 15, the conductor 2, the magnet 25 of the semaphore 6, and the magnet to earth.

Of the device 3 the circuits consist of the terminal 151, the conductor 3*, the magnet 26 of the semaphore 5, and the magnet to earth, the terminal 15, the conductor 3b, the magnet 25 of the semaphore 5, and the magnet to earth.

The two circuits of the device 4 consist of the terminal 15, the conductor 4a, the magnet 25 of the semaphore 5, and the magnet to earth; and the terminal 151, the conductor 4th, the magnet 26 of the semaphore 5, and the magnet to earth.

The connection of the magnets to earth is effected in any known manner.

The arrangement works in the following manner z-The roller of the trolley of the car, on coming into contact with the movable yoke 8 of the device for taking current (Fig. 2) raises it, and the lever 10 is rotated around the point 11. In `consequence of this the projection 13 bears against the extremity of the rod 14 of the interrupter 15, and pushes this rod upward so that the blades 16 establish a metallic connection in the interrupter 15 which allows current to iow. This current is conducted as required either to the electrofmagnet 25 which is intended to effect the signal that the line is blocked or to the electro-magnet 26 which is intended to effect the signaling of line clear. In Fig. 3 is shown the signal for line vclear the disk 27 being turned edgewise; the disk is held in this position by the pressure exercised by the shaft 18 against the end of the lever 31', ythis pressure overcomi-ng the strength of the spring 32.

Supposing that a car enters the single track and that the device for taking current for signaling that the line is blocked is operated by the trolley of this car, the current will excite the electro-magnet 25. The latter will raise the lever 23 which engages one of the pins of the wheel 2O and will cause this wheel to rotate a quarter of Ia turn; owing to'this rotation ofthe wheel 2O and of the engagement of the nut provided in the hub of the wheel with the threads of the shaft 18, the latter which is held by the key of the wheel 21 (the `motion of this wheel being arrested in its turn bythe lever 24) is displaced longitudinally a distance 'of a centimeter from the left toward the right. In consequence of this displacement, the shaft 1-8 ceases to press against the head of the lever 31, and the spring 32 then begins to operate, rotating the 'shaft 28 and consequently the disk 27, into the position represented by dotted lines in Fig. 3, that is to say, into the position corresponding to the signal thatl the line is blocked. Let us suppose now that it is required to give the signal for line clear The device for takingcurrent being operated by the trolley Q of the car, the current'is made tol excite the electro-magnet 26 and thus raise .the leverl 24, the projection on which engages one of the pins of the wheel 21 causing it to rotate through a quarter turn. The rotation of the `wheel 21 causes, by'means of the key already j mentioned, rotation ofthe screwed shaft A18, l which, since it engages with the nut pro` vided in the hub ofthe wheel 2()k is consei quently displaced longitudinally to the extent of one centimeter from the right to the left. The shaft 18 therefore contacts again with the end of the lever 31 and the system 31, 30, 29 is so operated as to overcome the resistance of the spring 32, and to turn the shaft 28 and the disk 27 into the position for signaling line clear. In the same manner, if, instead of one car, three cars for example, enter the single track, the wheel 2O will be rotated three quarters of a turn and the shaft 18 will be displaced from the left toward the right to the extent ,of three centimeters. In order to signal line clear it will therefore be necessary to displace the said shaft 18 three centimeters in the opposite direction, that is to say, the wheel 21 must be rotated three quarters of a turn which corresponds to the exit of three cars. In one word if a certain number of cars are on the single track, an equal number should leave in order that the semaphore shall give the signal line clear This arrangement also has the advantage that if two cars, following each other on the same line, arrive at the same instant, one at the point of entry on the single track and the other at the point at which the single track is left, the working remains suspended. In fact, in this case since the wheels 20, 21 turn simultaneously, their action on the screwed shaft 18 is reciprocal and equal and therefore the shaft will turn without being displaced in one direction or in the other.

In order to obviate the inconveniences which arise in the case when a car having 'passed the point at whichthe single track Vis left must be drawn back, onto the single track, the devices for taking current are provided with two oil interrupters, one of which operates when the line is blocked, the other when the line is cleared. As will be seen in Fig. 2 the communication with these interrupters is established respectively by the projections 13, 13 of the levers 10, 10. Owing to this arrangement, each time that a car is drawn back, for any reason, after having operated the interrupter which is intended for signalingv line clear, the moving back will have for its effect to determine the action of the other interrupter in the opposite direction, so aslto suspend the signaling of line clear. This signal will only be made again when the ear again leaves the single track. The same applies for the kcase when a car having passed the point of entry on the single track and determined the action ofthe blocking device, is for any reason moved back.

What I claim is 1. The combination with a block system for tramways of a signaling device comprising two magnets, cores operated by said magnets, wheels adapted to be rotated by said cores, a screwed shaft having a key Way and passing through said wheels, one of said wheels having a screw thread corresponding to the screw on the shaft, a key in the other wheel engaging with the key way of the shaft, a semaphore, means connecting the semaphore to the screwed shaft, and means for energizing the magnets.

2. The combination with a block system for tramways of a signaling device comprising two magnets, cores operated by said magnets, wheels adapted to be rotated by said cores, a screwed shaft having a key way and passing through said wheels, one of said wheels having a screw thread corresponding to the screw on the sha-ft, a key in the other wheel engaging with the key way of the shaft, a semaphore, means connecting the semaphore to the screwed shaft, and means for energizing the magnets, said means comprising two interrupters of which one closes the circuit for one magnet and the other closes the circuit for the other magnet when operated by a car moving onto or off the single track.

3. The combination in a block system for tramways of a screwed shaft having a key way, two wheels mounted on said shaft, one of said wheels having an internal screw thread corresponding to the thread of the shaft, a key in the other wheel corresponding to the key way in the screwed shaft, pins on said wheels, magnets, cores, said cores engaging with said pins, a rotary shaft, a semaphore mounted on said shaft, means adapted to retain the rotary shaft in the normal position, and means connecting the rotary shaft to the screwed shaft.

In testimony whereof I aIiX my signature in presence of two witnesses.

DINO DAVIDE SAMAIA.

Witnesses ALBERT PERI, GIRUEP GRIFFE.

Copies of this patent may be obtained for ive cents each, by addrelsing the Commissioner ot latents, Washington, D. C.

Images