GB2203335A - Escape devices - Google Patents

Abstract

An escape device for making a controlled descent comprises a cable, a cable gripping pulley (42), a brake (5) and a speed adjusting means (7). The pulley (42) has a V-shaped knurled surface (42) for tightly gripping the cable and actuation of the speed adjusting means (7) urges the brake (5) against the pulley (42) to control the speed of the pulleys rotation. By controlling the rotating speed of the pulley, any person of any weight can easily, conveniently and safely use the device. <IMAGE>

Description

I'?OVEIENTS PELATING TO ESCAPE DEVICES The present invention relates to an escape, and more particularly to an escape capable of speed-controlling.

In recent society, land price goes higher and higher; so does the building. As the building is goring higher, great attention must be paid to the escaping equipment.

The fact that domestic and foreign building fires in the near past always resulted in a disaster reveals that recent high buildings do not have effective or enough escaping devices. Although the building has the provision of electric elevator, it always becomes out of order upon a fire because of the power interruption.

Viewing the above, there has been marketed a kind of "fire escape" by which one can descend himself slowly down to the ground. Its working theory is that a rope suitably fastening the person is guided through a braking mechanism by means of which he is able to slowly descend down. So far as the operation theory is concerned, it should be a safe and utility facility. However, due to its high price and other factors to be briefly discussed below, it is rare that a building is provided with such an escape.

(1). In order to obtain a slow descent, the fire escape must include a reduction gear assembly and a speed-controlling mechanism which will result in the escape to be bulky. Thus, it is not considered safe for a child to use it without being accompanied by an adult.

(2). The speed-controlling mechanism utilizes a fixed braking piece or the damping force of a dense liquid. For the former, the fire escape will be incapable of being safely used if the braking piece is abraded and for the latter, it would be dangerous if there is a liquid leakage which causes the impossibility of speedcontrolling.

(3). The surface of the cable gripping pulley for gripping the rope is provided with radially distributed straight teeth which cannot directly grip tightly the cable if the cable is not covered with a cotton layer.

However, an increased diameter will mean an increased volume and weight. In addition, the cotton layer is subject to be ruined while being gripped by the cable gripping pulley and is inclined to catch a fire while meeting a flame both of which are dangerous.

(4). While being put into use, the fire escape must be bridged between walls on, e.g. the balcony and thus, its use is limited.

Seeing the inherent shortcomings of the fire escape described above, it is therefore attempted by the Applicant to create an escape as the present invention.

It is an object of the present invention to provide an escape in which the gripping surface of the cable gripping pulley is barb-shapedly knurled for capable of gripping directly the cable which thus calls no more for the covering of cotton or glass fiber and includes no additional volume or weight. The present escape can have a dimension of around the size of a fist and have a weight of not more than 0.3kg.

It is a further object of the present invention to provide an escape which is simple in structure and is capable of speed-controlling while one's descending.

It is yet an object of the present invention to provide an escape the cable of which has an end which can easily be secured to a fixing article.

It is an additional object of the present invention to provide an escape the cable guide of which is sleeved with a plastic soft tube the flexibleness of which aids to avoid the tangle of the cable.

The present invention will be best understood through the description of a preferred embodiment with reference to the accompanying drawings, in which: Fig. 1 is an exploded view of a preferred embodiment of an escape according to the present invention; Fig. 2 is a perspective view of an assembled escape according to the present invention; Fig. 3A is a plan view showing the components associated with the lower casing of an escape according to the present invention; Fig. 3B is a sectional view showing an assembled escape according to the present invention; Fig. 4A is a perspective view showing the cable gripping pulley of an escape according to the present invention; Fig. 4B shows a first pattern of the knurled surface of the cable gripping pulley of an escape according to the present invention;; Fig. 4C shows a second pattern of the knurled sur face of the cable gripping pulley of an escape according to the present invention; Fig. 5 is a perspective view schematically showing a cable engaged in a cable reel for use in an escape according to the present invention; Fig. 6 shows a safety belt and a triangular hook for use in an escape according to the present invention; Fig. 7 is a sectional view schematically showing the operation of a positioning pin assembly of an escape according to the present invent ion; and Fig. 8 is a perspective wiew of an escape according to the present invention, schematically showing the operation of a plastic soft tube for the present escape.

Referring now to Figs. 1 & 2, there is shown a preferred embodiment of an escape according to the present invention, which includes a lower casing 11, a pulley 2, a cable guide 3, a cable gripping pulley assembly 4, a pressing piece 5, an upper casing 12, a positioning pin assembly 127, an elastic annulus 6, a pressure adjusting piece 70, a speed-controlling medium 7, plastic soft tubes 8 and a cable 9 which, in this embodiment, can be a 3mm steel cable, can bear a load of 1000kg and has each end secured to a hook 91 (shown in Fig. 5).

Lower casing 11 has a rectangular crosssection and a centrally and cylindrically shallowed first portion 112 the bottom of which is attached to a braking piece 114 which has a central through hole 1141 and a plurality of radial debric escaping grooves 1142. Shallowed portion 112 has a central through hole 113 in which a bearing 1131 is tightly fitted. Lower casing 11 further includes a second shallowed portion 111 at each side of which there is provided with a pulley shaft 115 near which there is provided with a screw hole 116 connected to cable hole 1161. Lower casing 11 also includes 4 screw holes 117, a handle 118 and a plurality of heatdissipating holes 119 for braking piece 114.

-Pulley 2 being surface-heat-treated has a shaft hole 21 the inner diameter of which can be, e.g. 0.1mum larger than the outer diameter of pulley shaft 115 to be rotatably mounted thereon.

Cable guide 3 being heat-treated has a central through guide hole 31 the inner diameter of which can be, e.g. 0.1mum larger than the diameter of the cable and has an outer surface provided with screw threads for being screwed into screw hole 116. Cable guide 3 also has a tapered front which can also be provided with screw threads for being tightly sleeved by plastic soft tube 8 by the flexibleness of which cable 9 is smoothly guided there through.

Cable gripping pulley assembly 4 includes a shaft 41 and a gripping pulley 42 including a first half 421 and a second half 422 each of which has a part of the outer portion tapered, barb-shapedly knurled (as shown in Fig. 4B) and heat-treated. By having the two tapered outer portions faced to each other and the two halves sleeved on shaft 41 having screw threads and by means of the assistance provided by a nut 43 and a key 44, the two tapered portions constitute a cable gripping surface. The outer diameter of gripping pulley 42 can be, e.g. 0.2mm smaller than the diamter of shallowed portion 112.In addition, the two halves can be an integral piece being at the middle of the outer portion provided with a V-shaped groove on the surface of which tooth pattern having a pitch the same as that which cable 9 is wound is directly moulded to constitute a cable gripping surface (as shown in Fig. 4C).

pressing piece 5 being circular and provided with two stopping ridges 51 is attached at its one side to a braking piece 52. Pressing piece 5 and braking piece 52 have a central through hole 53.

Upper casing 12 being matchable to lower casing 11 is centrally provided with a threaded hole 121 which can have a diameter smaller than that of portion 112 and is provided with two stopping grooves 122 capable of sliding therein ridges 51. Upper casing 12 further includes four screw holes 126 corresponding to holes 117 and can be provided with two holes for receiving therein the top ends of shafts 115 when casings 11, 12 are matched together. The body 124 forming hole 121 has a protrusion 125 in which there is provided with a through screw hole 1251 communicating with hole 121.

Positioning pin assembly 127 to be received in hole 1251 includes a pressing screw 1271, a spring 1272 positionable in a recess provided in screw 1271 and a positioning pin 1273 urged against by spring 1272.

Elastic annulus 6 having a central through hole 61 is provided between pressing piece 5 and a pressure adjusting piece 70.

Speed-controlling medium 7 being circular includes a head portion 77 and a threaded portion 75. Head portion 77 is provided with a groove 71 for receiving therein an actuating arm 73 which is retained therein b a pin 74 pinning through two holes 72 provided at two sides of groove 71. Threaded portion 75 has an inclined recess 76 and a centrally shallowed portion 751 (shown in Fig. 3B) connected to a central through hole 78 tightly fitting therein a bearing 781.

As complementarily shown in Figs. 3A & 3B, the present invention will be further described.

After cable gripping pulley 42 is fixed to shaft 41 and cable 9 is wound on the cable gripping surface, one end of shaft 41 is inserted into bearing 1131 in hole 113 so that cable gripping pulley 42 is in portion 112.

Cable 9 is guided by pulleys 2 and then passes through guide hole 31 of cable guide 3. The situation can be that at first, cable 9 passes guides 3 and after the correct location of pulley 42 and cable 9, cable 9 is put into holes 116 through holes 1161 and thereafter, guides 3 sleeving thereon with plastic soft tubes 8 are screwed into holes 116. Then, casings 11, 12 are matched together and fixed by screws.

After casings 11, 12 are assembled, stopping ridges 51 on pressing piece 5 are slid in stopping grooves 122 on upper casing 12, elastic annulus 6 and pressure adjusting piece 70 are also sleeving on shaft 41 and threaded portion 75 is screwed into hole 121. After another end of shaft 41 is inserted into bearding 781 in hole 78, the present escape is completely assembled.

The present invention is to be used in cooperation with a safety belt (as shown in Fig. 6) and a cable reel (as shown in Fig. 5) both of which are not the subjects of the present invention and will not be detailedly described. The cable reel has a groove for retaining therein a hooked end of cable 9 before it is wound on the reel. The safety belt has loops for the limbs of a person and has a hook 100 for handle 118. Furthermore, the cable reel is also fastened to the safety belt.

In use, the hook 91 on one end of cable 9 is guided to wind around a secured article and then hooks on cable 9; actuating arm 73 is rotated to have braking piece 52 tightly urge against cable gripping pulley 42; after the escaping person has climbed out of the building, by rotating the actuating arm 73 in opposite direction to decrease gradually the frictional force braking pieces 114, 52 exert against gripping pulley 42, the lowering speed of the person will be controllable by himself.

It can be noticed that the person can stop his descending travel at the half way so that he can have another person at a lower floor accompanied by him to complete his escaping travel. For safety purpose, the present escape is provide with a safeguarding means which is the positioning pin assembly 17, as further shown in Fig. 7. When actuating arm 73 is rotated to decrease the frictional force between pieces 114, 52 and gripping pulley 42 to a predetermined position, positioning pin 1273 will engage in recess 76 to result in no more possibility of further rotaton of arm 73 with respect to casings 11, 12 so that the largest lowering speed is governed and safety belt is ensured. The predetermined position can be set as corresponding to a eight of 100 kg at 60 m/min.

As can be knon from the above description and structure, the present escape can have a small volume and be lowly priced. With the top hook 91 being freed and the free hook 91 being wound around the fixing article, the present escape can be used again.

As shown in Fig. 8, plastic soft tube 8 aids to smoothly guide cable 9 to pass through guide 3.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment but on the contrary, is intended to cover various modifications and equivalent arrangements incuded within the spirit and scope of the appended claims which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures.

Claims (11)

1. An escape device for making a descent comprising a cable, means for gripping said cable which are movable along the cable and adjustable means for controlling the speed of descent.

2. An escape device as claimed in Claim 1 in which the cable gripping means comprise a pulley assembly which moves along the cable as a pulley rotates.

3. An escape device as claimed in Claim 2 in which the pulley assembly comprises a pulley having tapered knurled flanges forming a V-shape in its outer edge to grip the cable.

4. An escape device as claimed in any one of the preceding claims in which the speed controlling means comprises a brake.

5. An escape device as claimed in Claim 4 in which the brake is a manually adjustable friction brake operable to control the speed of rotation of the pulley assembly.

6. An escape device as claimed in any one of the preceding claims further comprising a limiting device to limit the maximum speed of descent to a predetermined speed.

7. An escape device as claimed in any one of the preceding claims further comprising flexible cable guides to guide the cable towards and away from the gripping means.

8. An escape device comprising a lower casing, including a centrally and cylindrically shallowed first portion the bottom of which is attached to a braking piece having a hole therethrough, and a second shallowed portion at each side of which there is provided a pulley shaft, near which there is provided a screw hole connected to a cable hole, said first portion having a central through hole; two threaded guides, each being rotatably mounted on said pulley shaft; two threaded guides, each being screwable into said screw hole and having a guide hole; a cable gripping pulley assembly having a shaft which has an end received in said through hole and said central through hole, and a gripping pulley including a first half and a second half each of which had a part of the outer portion tapered and knurled and capable of being received in said first shallowed portion; a pressing piece provided with two stopping ridges and attached at its one side to a second braking piece; an upper casing matchable to said lower casing, and provided with a threaded hole on which two stopping grooves are provided for sliding said ridges,therein the body forming said threaded hole having a protrusion in which there is provided a through screw hole communicating with said threaded hole; a positioning pin assembly received in said through screw hole and including a pressing screw, a spring and a positioning pin; a speed-controlling medium including a head portion attached to an actuating arm, and a threaded portion having an inclined recess engagable with said positioning pin and screwed into said threaded hole in order to urge against said pressing piece; and a cable passing through said cable gripping pulley assembly, said pulleys and said threaded guides.

9. An escape device as claimed in Claim 8 wherein the two halves of the gripping pulley are integrally formed together.

10. An escape device as claimed in Claim 8 or Claim 9, further comprising two soft plastic tubes sleeved on the free ends of said threaded guides, by the flexibility of which tubes, the tangle of said cable is avoided.

11. An escape device substantially as hereinbefore described with reference to the accompanying drawings.