GB2292722A

GB2292722A - Braking a slant type passenger conveyor

Info

Publication number: GB2292722A
Application number: GB9517393A
Authority: GB
Inventors: Kazuhira Ojima; Chuichi Saito
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 1994-08-26
Filing date: 1995-08-24
Publication date: 1996-03-06
Anticipated expiration: 2015-08-24
Also published as: JP3018915B2; CN1039000C; KR960007424A; JPH0859161A; CN1117939A; GB2292722B; GB9517393D0; HK25397A

Abstract

In a slant type passenger conveyor comprising a main frame 1 installed on upper and lower floors separated from each other, a plurality of steps 3 are arranged in the main frame, connected to a step chain 2 and movable along with said step chain. A drive machine 8 is arranged in the main frame for driving the step chain wound on sprockets 4, 5, and a brake device is provided for imparting braking force to a rotating shaft 16 of the drive machine. A latch means 18 is further provided for restraining rotation of the shaft 16 by engaging a portion 17 rotatable with the shaft 16, with a fixed portion of the drive machine. <IMAGE>

Description

A SLANT TYPE PASSENGER CONVEYER The present invention relates to a slant type passenger conveyer such as an escalator mounted slantly on upper and lower floors separated from each other in an up and down direction, an moving walk and, more particularly, to a slant type passenger conveyer in which steps are surely fixed during stoppage thereof.

Hitherto, a slant type passenger conveyer, for example, an escalator rotates a driving sprocket through a reduction gear by an electric motor, moves circularly a step chain wound on the driving sprocket and a follower sprocket pairing with the driving sprocket, and move a plurality of steps connected to the step chain.

And, the steps are stopped and held by operating a brake device provided on a drive machine at time of stop.

Further, at the time of stop of the steps, in case load is applied by boarding of passenger when the brake device loses its function for trouble or other reasons, the steps may descend. In order to prevent it, an escalator is proposed to lock the above-mentioned driving sprocket, which is disclosed in Japanese patent laid-open application (JP A) 59-97985.

The above-mentioned prior art has a problem such that since the driving sprocket of large diameter is directly locked, its mechanism itself is made large scale, and since there is no space for arranging such a lock mechanism around the driving sprocket, application of the mechanism to a practical escalator makes the escalator large-scale.

Preferably the present invention provides a slant type passenger conveyer in which the steps can be stopped and held at time of stop by a small-sized apparatus.

Preferably the present invention provides a slant type passenger conveyer which is simple in construction and in which the apparatus is able to be easily applied after delivery.

In order to achieve the above, the present invention provides means for restraining by engaging a rotating portion of the drive machine in a slant type passenger conveyer which comprises a main frame installed slantly on upper and lower floors separated from each other in an up and down direction, a plurality of steps arranged in the main frame, connected to a step chain and moving along with the step chain, the drive machine arranged in the main frame, having a sprocket wound by the step chain, and driving the step chain, and a brake device imparting braking force to a rotating shaft of the drive machine.

According to the above-mentioned construction, since it is constructed so as to provide restraint means by engaging with the rotation portion of small diameter at a side of the drive machine far from the sprocket wound by the step chain, rotating force applied on the restraint means becomes small, as a result, it is possible to stop and hold the steps with a small apparatus. Further, there is relatively a space around the drive machine, so that the apparatus also can be applied to a delivered conveyer.

Embodiments of the present invention will now be described with reference to the accompanyinq drawings.

Fig. 1 is a vertical sectional view showing a drive machine with restraint means and its suroundings according to the present invention; Fig. 2 is an enlarged plan view of the drive machine shown in Fig. 1; Fig. 3 is a side view showing the entire of an escalator; Fig. 4 is a schematic diagram of a control system of each apparatus shown in Figs. 1, 2; and Fig. 5 is a vertical sectional view showing surrounding of a drive machine with another restraint means according to the present invention.

An embodiment of a slant type passenger conveyer according to the present invention is explained hereunder, referring to Figs. 1 to 4. The slant type passenger conveyer shown here is an escalator, in which a plurality of steps 3 connected endlessly to a step chain 2 are guided so as to circulate in a main frame 1 arranged slantly between an upper floor UF and a lower floor LF separated from each other in an up and down direction. The steps 3 is duided by a guide rail (not shown) supported by the above-mentioned main frame 1.

The above-mentioned step chain 2 is wound on and driven by a driving sprocket 4 and a follower sprocket 5 which are supported on an upper machine room 1A and a lower machine room 1B which are formed at end portions of the main frame 1, respectively.

The driving sprocket 4 is fixed to a shaft on which a driven sprocket 6 is fixed. A drive chain 7 is wound on the driven sprocket 6, and transmits rotation force of a drive machine 8 to the driving sprocket 4.

The drive machine 8 is provided with a brake device 9 which imparts braking force to a rotating shaft, such as an electromagnetic disk brake which generates braking force by spring force and releases the braking force by electromagnetic force by supplying electric power to a coil.

Further, balustrade panels 10 are arranged along the moving direction of the endless steps 3 on both sides of the steps, and moving handrails 11 are supported around the periphery thereof, which handrails 11 are driven in synchronism with the steps 3.

The above-mentioned upper machine room 1A and the lower machine room 1B are chocked with a boarding floor 12A, 12B, respectively.

On the other hand, the drive machine 8 comprises an electric motor 13 and a reduction gear 14. A rotating shaft 16 of the electric motor 13 is connected to an input shaft of the reduction gear 14, a sprocket 15 is provided on an output shaft of the reduction gear 14, and the drive chain 7 is wound thereon.

Further, the above-mentioned brake device 9 is provided on an input shaft of the reduction gear 14.

The above-mentioned reduction gear 14 is a so-called parallel axis reducer in which the input shaft and the output shaft are arranged in parallel to each other, and which uses a helical gear.

The above-mentioned construction is a construction of usual escalator. The present embodiment is characterized in that a restraint means is provided for restraining a rotating portion of the drive machine 8 relative to a fixed portion by engaging therewith. That is, the restraint means is constructed by providing a claw wheel 17 on the rotating shaft 16 of the electric motor 13 and providing a latch 18 on the fixed member, and even if the brake device 9 falls into a condition in which its operation is impossible it is made so as to be able to stop and hold the steps 3 by engaging both of them when the steps 3 are stopped.

The claw wheel 17 has a plurality of claw portions 17C formed around the outer periphery. The claw wheel 17 can be provided by a coupling connecting the rotating shaft 16 of the electric motor 13 and the input shaft of the reduction gear 14 by forming a plurality of claw portions 17C on the outer periphery of the coupling, whereby it is unnecessary to provide a new claw wheel and it is unnecessary to secure a space for placing the new claw wheel.

However, in case the rotating shaft 16 of the electric motor 13 and the input shaft of the reduction gear 14 are made of one piece shaft so that any coupling is unnecessary to be used for connection, the claw wheel for exclusive use should be provided. In this case, the claw wheel 17 can be set only by making each of the distance between the electric motor 13 and the reduction gear 14 and the one piece shaft a little larger, so that it is unnecessary to secure a large space for newly providing the claw wheel.

The latch 18 is formed in a L-letter-like shape. An engaging portion 19 engaging with the claw portions 17c of the claw wheel 17 is formed at one end of the Lletter-like latch 18, and a bent portion of the latch 18 is rotatably supported on a box of the reduction gear 14 by a support shaft 20.

The other end of the L-letter-like latch 18 is connected to an electromagnetic drive apparatus 21 which is a means for operating the latch 18. The electromagnetic drive apparatus 21 is fixed to the abovementioned box of the reduction gear 14, and comprises a coil (not shown) for generating magnetic force by supplying electric power, a plunger 22 driven by generation of the magnetic force, and a return spring 18S for returning the plunger 22 having been driven to an original position. The plunger 22 has a free end connected to the other end of the L-like shaped latch 18 by a pin.Further, the return spring 18S generates pressing force so that the engaging portion 19 at the one end of the L-letter like latch 18 always engages with the claw portion 17c of the claw wheel 17, and the abovementioned coil is constructed so as to generate magnetic force driving the plunger 22 in the direction in which the engagement between the engaging portion 19 and the claw portion 17C is released.

Further, a detection switch 23 is fixed to the box of the reduction gear 14, and the switch 23 is positioned at an opposite side to the engaging portion 19 at the one end of the latch 18.

In the above construction, when the escalator is stopped, the electric motor 13 is interrupted to supply power from a power source, and the electric motor 13 is restrained by the brake device 9 through the input shaft of the reduction gear 14. In this manner, the drive machine 8 is restrained, so that the movement of steps 3 also is stopped through the drive chain 7 and the step chain 2.

At this time, assuming that a reduction ratio between the driven sprocket 6 and the sprocket 15 is about 1/4, and a reduction ratio between the sprocket 15 and the rotating shaft 16 is about 1/16 to 1/17, a total reduction ratio becomes 1/64 to 1/68. Assuming that passenger load which tends to rotate the driven sprocket 6 is F, rotating force F' acting on the claw wheel 17 of the rotating shaft 16 becomes F/64 to F/68 (F'= F/64 to F/68) which is very small. Therefore, the claw wheel 17 and the latch 18 can be made small-size.

In this manner, when the steps 3 are stopped and held by the brake device 9, at the same time the latch 18 also is engaged with the claw portion 17c of the claw wheel 17 at the engaging portion 19 thereof. Therefore, even if a lot of passengers beyond the capacity of stop and hold of the brake device 9 ride on or even if a lot of passengers ride on when the brake device 9 is out of order during stoppage to lose the stop and hold ability, the steps 3 do not move downward because the rotating shaft of the drive machine 8 is restrained by the latch 18.

Next, when an operation instruction is issued in a stop condition of the above-mentioned escalator, the coil of the electromagnetic drive apparatus 21 generates magnetic force by supply of power through a controller 24, and attracts the plunger 22 against the pressing force of the return spring 18S. By the attraction of the plunger 22, the other end of the L-letter like latch 18 turns around the support shaft as the center, the engaging portion 19 of the one end of the L-letter-like latch 18 is separated from the claw wheel 17 to release the engagement.In this manner, when the latch 18 is turned to a position at which the engagement between the engaging portion 19 and the claw portion 17C is released, the one end of the L-letter-like latch 18 operates the detection switch 23, and the operation of the detection switch 23 carries out power supply to the brake device 9 to release the braking force and starts the electric motor 13 to operate the escalator.

Further, in case the escalator under operation is stopped, when an operation stop instruction is issued, the electric motor 13 starts to reduce the speed through the controller 24, the power supply to the brake device 6 is stopped to impart braking force at time of or immediately before the stop of the electric motor 13, whereby the rotating shaft of the drive machine 8 is stopped and held. At the same time as the brake device 9 imparts the braking force, in the other words, at the same time as the power supply to the brake device 9, the power supply to the coil of the electromagnetic drive apparatus 21 is interrupted.By the interruption of the power supply to the coil of the electromagnetic drive apparatus 21, the magnetic force disappear from the coil and attraction of the plunger 22 is released, the plunger 22 presses the other end of the L-letter-like latch 18 by pressing force of the return spring 18S in the electromagnetic drive apparatus 21, and the latch 18 is turned around the support shaft 20 as the center. By the turning of the latch 18, the engaging portion 19 on the one end side of the L-letter-like latch 18 approaches to the side of the claw wheel 17, engages with the claw portion 17C, and restrains the rotating shaft of the drive machine 8.

In the above-mentioned explanation, power supply to the coil of the electromagnetic drive apparatus 21 is interrupted at the same time as the braking force is imparted by the brake device 9, whereby the rotating shaft of the drive machine 8 is restrained. In this case, there is no problem if power supply to the brake device 9 and the electromagnetic drive apparatus 21 is stopped at the same time as the electric motor 13 is stopped.

However, in case power supply to the brake device 9 is stopped immediately before the electric motor 13 stops, even if the braking force is imparted, the escalator moves a little because of its inertia. In this case, therefore, when the power supply to the electromagnetic drive apparatus 21 is stopped at the same time, such dangers may happen that stop shock occurs at the instance of the engagement between the engaging portion 19 and the claw portion 17C, the engaging portion 19 and the claw portion 17C are broken and peripheral apparatus such as the reduction gear 14 is broken.

Such disadvantages as mentioned above disappear by delaying the stop of power supply to the coil of the electromagnetic drive apparatus 21 by a delay means.

That is to say, it is enough to provide the controller 24 with a timer 25 which works by a power supply stop signal as a reference so that the stop of the power supply to the electromagnetic drive apparatus 21 is effected after lapse of a certain time ( it is a longer time than time after imparting of the braking force until the escalator stops) after the power supply to the brake device 9. The stop of the escalator is confirmed, for example, by pulse of a rotary encoder 26 provided on the rotating shaft of the electric motor 13 to use it as a confirmation signal to the controller 24.

By providing such a timer 25, the engagement between the engaging portion 19 and the claw portion 17C can be effected after the movement of the escalator due to its inertia terminates, so that breakage of apparatuses can be prevented.

Further, the above-mentioned delay means is an electric delay means by the controller 24, however, it can be a mechanical delay means as shown in Fig. 5.

Namely, it is constructed so that a one-way damper 27 is connected to the L-letter-like latch 18 at the other end thereof through a rod 28 of the damper 27, which latch is connected to the plunger 22 of the electromagnetic drive apparatus 21 by a pin. The one-way damper 27 has a damping function only in one direction, when the other end of the latch 18 is attracted by energization of the coil of the electromagnetic drive apparatus 21 through the plunger 22, the damper has no function of damping so that it moves rapidly, on the contrary, when the built-in return spring presses the plunger 22 by de-energizing of the coil of the electromagnetic drive apparatus 21 to project and press the other end of the latch 18, the damper has a damping function so that it moves slowly.

By pressing the other end of the latch 18 to return slowly, the time until the engaging portion 19 engages with the claw portion 17C can be made long, as a result, the engaging portion 19 and the claw portion 17C can engage with each other after movement of the escalator due to its inertia terminates. By adjusting the slow movement time so that slow movement terminates after a certain time lapse after imparting braking force by the brake device 9, as mentioned above, breakage of the peripheral apparatuses can be prevented.

The above-mentioned explanation is on the escalator, however, it can be, of course, applied to an moving walk if it is arranged slantly.

As mentioned above, according to the embodiment, the restraint means is provided for restraining by engaging between the rotating portion and the fixed portion of the drive machine, whereby the steps at time of stop can be stopped and held with a small apparatus, and the apparatus is small in scale and provided around the rotation portion of the drive machine, whereby it can be easily applied to passenger conveyers already made and set.

As mentioned above, according to the present invention, the steps at time of stop can be stopped and held by a small sized apparatus, and a slant type passenger conveyer can be obtained which is simple in construction and the apparatus can be easily applied to delivered conveyers.

Claims

What is Claimed is:

1. A slant type passenger conveyor comprising a main frame installed slantly on upper and lower floors separated from each other, a plurality of steps arranged in said main frame, connected to a step chain and moving along with said step chain, a drive machine arranged in said main frame and driving said step chain, and a brake device imparting braking force to a rotating shaft of said drive machine, characterized in that a restraint means is provided for restraining by engaging a rotating portion and a fixed portion of said drive machine.

2. A slant type passenger conveyor as claimed in claim 1, said brake device comprising a reduction gear having a sprocket wound by said step chain, said conveyor including an electric motor for driving said reduction gear, and an operation means for operating said restraint means.

3. slant type passenger conveyor according to claim 2, characterized in that said operation means is constructed so that the restraint due to engaging of said restraint means is released by supply of electric power, and the restraint by engaging said restraint means is possible by interruption of the power supply.

4. A slant type passenger conveyor according to claim 2, characterized in that said restraint means is provided at a side of an input shaft of said reduction gear.

5. A slant type passenger conveyor according to claim 1 including a confirming means for confirming the restraint and release of said restraint means, and a control apparatus for releasing braking of said brake device on the basis of a confirming signal of said confirming means.

6. A slant type passenger conveyor according to claim 1 comprising an operation means for operating said restraint means, linking with operation of said brake device.

7. A slant type passenger conveyor according to claim 1 comprising an operation means for operating said restraint means and a control means for controlling said operation means.

8. A slant type passenger conveyor according to claim 7, characterized in that said control means is constructed so that stoppage of moving of said steps is confirmed and then an instruction for releasing the restraint is given to said operation means.

9. A slant type passenger conveyor according to claim 1 comprising an operation means for operating said restrain means, a confirming means for confirming stop of said steps and a control means for controlling operation of said operation means on the basis of a confirming signal from said confirming means.

10. A slant type passenger conveyor according to claim 9, characterized in that said control means is constructed so as to operate said operation means after a certain time on the basis of a conforming signal from said confirming means.

11. A slant type passenger conveyor according to claim 1 comprising an operation means for operating said restraint means, and a control means for controlling said operation means, said control means being provided with a delay means for delaying said operation means.

12. A slant type passenger conveyor according to claim 1 comprising an operation means for operating said restraint means, and a control means for controlling said operation means, said restraint means being provided with a delay means for delaying a restraint operation.

13. A slant type passenger conveyor according to claim 12, characterized in that said delay means of said restraint means is a one way damper mechanism which damps in a direction of restraint of said restraint means and operates rapidly in a direction of release of the restraint.

14. A slant type passenger conveyor comprising a main frame installed slantly on upper and lower floors separated from each other; driving and follower sprockets which have shafts supported on an upper machine room and an lower machine room formed at an upper lengthwise end and a lower lengthwise end, respectively; an endless step chain wound on said driving and following sprockets and having a plurality of steps connected thereto; a driven sprocket fixed coaxially to said driving sprocket; a driving chain wound on said driven sprocket; a reduction gear having a sprocket wound by said driving chain; an electric motor for imparting rotation power to said reduction gear;; a brake device for imparting brake force to a rotating shaft of any one of said electric motor and said reduction gear, characterized in that a claw wheel is provided a rotating shaft of any one of said electric motor and said reduction gear, and a latch supported by a fixed portion opposing a claw portion of said claw wheel, a pressing member always pressing said latch toward the claw portion side of said claw wheel, an electromagnetic drive portion separating said latch pressed by said pressing member from said claw portion of said claw wheel, and a damper for slowing the returning speed of said latch separated from said claw portion to said claw portion less than the separating speed are provided.

15. A conveyor according to any one of the above claims wherein said drive machine has a sprocket wound by said step chain.

16. A conveyor substantially as any one embodiment herein described with reference to the accompanying drawings.