Clamping system for carriers of an automatic cableway installation

Abstract

 Binding system for carriers or telphers of an automatic cableway installation, said installation having at least two carrying cables (12) and at least one running cable (11), comprising a trolley provided with carrying wheels for the support on the carrying cables, at least one vice for binding the trolley to the running cable, a suspension arm (8) bound to such trolley, in turn connected with a suspension strut (17) for the support of the telpher.
The vice comprises two jaws which rotate in a symmetrical manner with respect to the entrance plane of the running cable, which is clamped.

Description

[0001] The present invention refers to a binding system for carriers of an automatic cableway installation of the type equipped with two carrying cables and one running cable.

[0002] The installations of this type are known among technicians with the initials 3S; the two carrying cables are usually parallel and at the same height, with a transverse distance between them typically in the range of 60-100 cm; the running cable is usually in the mid-plane between the two carrying cables, at a slightly lower height.

[0003] Supports are normally present on the line; the carrying cables lie on these supports with the interposition of suitable "shoes", while the running cable rests on rollers which are placed in rotation by the movement of the cable. In the longest spans, the running cable is also normally supported by rollers mounted in frames integral with the carrying cables, known by technicians with the name of "U-bolts".

[0004] In line, the carriers (spaced at regular intervals, typically in the range of 100-300 m) rest on the carrying cables by means of suitable trolleys, and are bound to the running cable which drives it by moving it at a constant speed (typically 6-8 m/sec); when a carrier reaches a terminal or intermediate station, suitable mechanisms release the trolley from the running cable, to slow the carrier, to stop it or to make it move at low speed at the unloading or loading zone, and then to accelerate it and bind it once again with the running cable. During the station transit, the trolleys of the carrier normally leave the carrying cables and transit on suitably-shaped rigid rails.

[0005] Cable installations are typically used as ski-lifts on mountain lines with considerable slope; however, for practical reasons, the acceleration and deceleration of the carriers in the stations occurs on rails arranged flat or with little slope; normally, at the exit of at least one of the stations, a more or less accentuated concavity is therefore present which requires the presence of deflection rollers placed atop the running cable to keep it parallel to the carrying cables and to the sliding rails of the carriers.

[0006] The above-described characteristics imply very narrow binding due to the geometry of the binding means of the carriers to the carrying cables and to the running cable. Such binding means are composed of support trolleys on the carrying cables and connection vices to the running cable; on the other hand, these being installations of heavy type characterised by the presence of carriers of considerable mass (typically 6000 kg), the forces in play for making the trolleys integral with the running cable and for manoeuvring the vices are very high. Moreover, when the trolley moves on the line supports, it is obliged to lift the running cable from its bases on the support, and this generates additional forces in the trolley which can also be much greater than those due to the weight of the loaded carrier.

[0007] In order to respect the contrasting requirements as outlined above, the trolleys and the vices intended for installations of this type are rather complex and heavy.

[0008] Object of the present invention is that of making binding means of the carriers to the installation equipped with a trolley and vices with suitable characteristics, so to satisfy the contrasting functional needs, permit simplifying the geometry of the terminal stations, and permit reducing the dynamic effects for the passengers and for the structures during the station manoeuvres.

[0009] Preferably, the trolley takes best advantage of its advantageous characteristics if it is equipped with vices functioning symmetrically with respect to the running cable plane.

[0010] One aspect of the present invention refers to a binding system for carriers or telphers of an automatic cableway installation, said installation having at least two carrying cables and at least one running cable, comprising a trolley provided with carrying wheels for the support on the carrying cables, at least one vice for binding the trolley to the running cable, a suspension arm bound to such trolley, in turn connected with a suspension strut for the support of the telpher, characterised in that said at least one vice has two jaws which rotate in a symmetrical manner with respect to the entrance plane of the running cable, which is clamped.

[0011] Further objects and advantages of the present invention are clear from the description which follows and from the attached drawings, provided as mere exemplifying and non-limiting example, wherein:

• Figure 1 shows a plan view of the trolley of the installation according to the present invention;
• Figure 2 shows a transverse view of the trolley at the passage over a line support;
• Figure 3 shows a lateral view of the trolley according to the invention;
• Figure 4 again shows a transverse view of the trolley with the carrier positioned in a terminal station during the manoeuvre of the vice according to the present invention;
• Figure 5 schematically and in front view shows the vice according to the present invention;
• Figure 6 shows a top view of a detail of the vice of figure 5;
• Figure 7 shows an enlarged detail of the vice according to an embodiment of the present invention;
• Figure 8 illustrates a further embodiment of the vice according to the present invention;
• Figure 9 illustrates a variant according to the present invention of the embodiment illustrated in figure 8.

[0012] With reference to the mentioned figures, the binding means of the carriers to the cableway installation comprise a trolley equipped with connection vices preferably comprising eight carrying wheels 1 intended to slide on carrying cables 12, coupled in four equalisers 2, in turn articulated to the ends of a rigid rectangular frame 3; the articulation of each equaliser with the frame permits a limited rotation in the plane of the wheels, but does not permit a rotation with regard to the horizontal plane (steering).

[0013] The rigid frame 3 is formed by two longitudinal members 4, two external crossbars 5 and by four internal crossbars 6. The external crossbars 5 are placed near the articulations of the equalisers 2, while the inner crossbars 6 support the mentioned vices 7 of connection to the running cable 11.

[0014] A suspension arm 8 is articulated between the two more internal crossbars 6, through a pin 9 or an equivalent device placed at a height slightly lower than that of said cables; said two vices are arranged symmetric with respect to said suspension arm, along an axis parallel to the carrying cables.

[0015] At the ends of the longitudinal members 4, four auxiliary wheels 10 are positioned, equipped with only one flange, used to permit the movement of the carrier on the curved station rails.

[0016] The auxiliary wheels are arranged inside, between the carrying cables, at a height such that the support plane on the rails is slightly lower than the carrying cables and slightly higher than the lower edge of said crossbars. Preferably, the auxiliary wheels are equipped with flange only on the internal side towards the running cable.

[0017] In figure 2, the trolley is illustrated at the passage over a line support; in the figure the position is recognised regarding the carrying wheels 1, carrying cables 12, running cable 11, auxiliary wheels 10, and suspension arm 8 in vertical position; the figure then shows the schematisation of a symmetrical vice 7 according to the present invention as illustrated in detail in the subsequent figures and the position of the friction blocks 15, used for dragging the carriers along the rails and the curves of the stations.

[0018] The particular shape of the trolley according to the invention permits the running cable 11 to pass under the holding rollers 13 without interferences with the vices 7, and to pass over the support rollers 14 with a limited lifting of the same running cable.

[0019] The trolley is shaped such to permit the transit at rollers placed atop the running cable, without said rollers coming into contact with any part of the trolley or vices installed on the trolley.

[0020] With dashed lines L, the possible transverse oscillations of the suspension arm 8 are illustrated, along with the position of the articulation pin 16 between the suspension arm 8 and the suspension strut 17; to subdivide the weight of the carrier in an optimal manner over the carrying wheels, such pin 16 must be at a height close to that of the running cable 11.

[0021] Moreover, the geometrical arrangement of the various elements of the trolley permits the insertion of guide elements 18 at the support rollers 14, capable of correctly positioning the running cable 11 in the groove of the rollers 14, also in the case of an irregular lateral movement after the lifting.

[0022] The running cable 11 is then maintained substantially rectilinear in the section comprised between the external crossbars 5 of the rigid frame 3; when the trolley passes on the line supports and lifts the running cable, the deflection of such cable predominantly occurs on the same crossbars 5, which transmit the corresponding load directly onto the carrying wheels 1, without straining the other elements of the trolley.

[0023] Said vices are aligned with each other and with said external crossbars so that when the trolley lifts the running cable at the passage over the line supports, said running cable sustains most of the deflection by being based on said two external crossbars and little or no deflection on said four internal crossbars.

[0024] Figure 4 shows a transverse view of the trolley with the trolley in a terminal station during the manoeuvre of the vice. In this step, the running cable 11 necessarily sustains an upward concave curving due to the holding rollers 13; the symmetrical-opening vices 7, preferably functioning without dead centre, are driven by a cam 19 which generates a system of forces in the trolley with no horizontal resultant and with limited and stabilising vertical resultant; once separated from the running cable, the carriers can be moved in the station by means of wheels 20 which act on the friction blocks 15; the shape of the trolley and of the vices permits drawing the mechanical power necessary for the dragging by the same holding rollers 13, for example by means of trapezoidal belts 21.

[0025] The carrying wheels 1 in the rectilinear path in the stations rest on sliding rails 23 and the auxiliary wheels 10, in the curved paths, rest on auxiliary rails 22. The same auxiliary rails 10 can be used for the paths in the storage rails.

[0026] As shown in figure 5, the vice 7 is perfectly symmetrical with respect to a vertical plane; it is formed by two jaws 71, each articulated with a fixed structure 76 in a pin 72. The jaws 71 clamp the cable 11 under the action of two elastic systems 75.

[0027] The pins 72 have axis substantially parallel to the running cable, and are placed near said symmetry plane and axis of the running cable, and are arranged in a substantially symmetric manner with respect to said plane.

[0028] The clamping force of said jaws on the running cable is provided by two distinct elastic systems, each acting on one of said jaws, arranged in a substantially symmetric manner with respect to said plane of symmetry.

[0029] In particular, each elastic system is articulated in the lower point 74 with the fixed structure 76, and with the jaw 71 in the upper point 73; in the jaw 71, the driving arm of the elastic system 75 with respect to the lower pin 72 is much greater than that of the running cable 11, and therefore the clamping force between the jaws and the cable is much greater than the force generated by the same elastic system.

[0030] In order to open the vice with moving carrier, one operates simultaneously and symmetrically on the two small wheels 79, for example with the wedge-shaped fixed cam 19. Due to the functioning symmetry, the horizontal components of the manoeuvring force are reciprocally compensated, and they do not strain the carrier in which the vice is inserted, nor the fixed structures which support the shaped cam; the vertical component, which strains the carrier and the fixed structures, is on the other hand kept within limited values by appropriately choosing the driving plane of the small manoeuvring wheels 79.

[0031] The articulation between the jaws 71 and the fixed structure 76 occurs through the pins 72 and a certain number of auxiliary horizontal connecting rods 77 which receive part of the horizontal reaction of the clamping force, and compensate it between the jaws 71 without affecting the fixed structure 76; moreover, the connecting rods increase the number of cut sections which affect the pins 72, permitting the reduction of the diameter and thus size of the vice below the running cable 11.

[0032] In figure 7, an embodiment is shown of the present invention in which between the two jaws 71 there is a gear tooth 713 which obliges the jaws to always move symmetrically, even in the presence of an asymmetric load of the two elastic systems 75, for example due to the yielding of a spring. The figure shows a gear tooth with bidirectional functioning; according to an alternative of the invention, not shown in the figures, the single bidirectional gear tooth is substituted by two unidirectional contact surfaces, placed on both sides of the jaw, adjacent to the two ends of the pins 72, made such to activate one contact surface or the other according to the direction of the stress imbalance.

[0033] Figure 8 shows a variant of the invention, in which the elastic system 75 is connected to the pin 73 of the jaw 71 with the interposition of an intermediate kinematic mechanism capable of resolving the force provided by the elastic system 75 by optimising the variation of the clamping force on the cable 11 as a function of the jaw rotation. The component of the elastic force which does not affect the jaw is discharged on the fixed structure 76. In particular, a first resolution system, illustrated in the left part of the figure, is obtained with an upper pin 717, in which two connecting rods 714 and 715 converge which connect the elastic system 75 respectively at the jaw 71 through the pin 73 and the fixed body 76 through the pin 716.

[0034] A second resolution system, illustrated in the right part of the figure, is obtained by substituting the connecting rod 715 with a surface of sliding or rolling by direct contact 718, which accomplishes the same function of the connecting rod; other systems, not represented in the figure, can instead foresee the use of sliding or rolling surfaces in place of the connecting rod 714, or at the place of both connecting rods.

[0035] According to a further improvement of the invention, illustrated in figure 9, the elastic system 75 is composed of two systems of helical springs 751 and 752 arranged symmetrically on both sides of each jaw 71.

Claims

1. Binding system for carriers or telphers of an automatic cableway installation, said installation having at least two carrying cables (12) and at least one running cable (11), comprising a trolley provided with carrying wheels for the support on the carrying cables, at least one vice for binding the trolley to the running cable, a suspension arm (8) bound to such trolley, in turn connected with a suspension strut (17) for the support of the telpher
characterised in that said at least one vice comprises two jaws which rotate in a symmetrical manner with respect to the entrance plane of the running cable, which is clamped.

2. System according to claim 1, wherein every one of said jaws of the clamp is individually articulated with the fixed support structure by means of a pin with axis substantially parallel to the running cable and placed near said plane of symmetry and the axis of the running cable, said two pins being arranged in substantially symmetrical manner with respect to said plane.

3. System according to claim 1, wherein said jaws are connected with each other at said two pins by other devices functioning as tie rods capable of absorbing and compensating the symmetrical forces exchanged between said jaws.

4. System according to claim 1, wherein the clamping force of said jaws on the running cable is provided by two distinct elastic systems (75), each acting on one of said jaws, arranged in a substantially symmetric manner with respect to said symmetry plane.

5. System according to claim 1, wherein, between the two jaws (71), there is a gear tooth (713) which obliges the jaws to always move in a symmetric manner, even in the presence of a load asymmetry of the two elastic systems (75).

6. System according to claim 5, wherein said gear tooth has bidirectional functioning.

7. System according to claim 1, wherein said gear tooth is composed of two unidirectional contact surfaces made so to activate one contact surface or the other according to the direction of the stress imbalance.

8. System according to claim 1, wherein the elastic system (75) is connected to the pin (73) of the jaw (71) with the interposition of an intermediate kinematic mechanism capable of resolving the force provided by the elastic system (75) by optimising the variation of the clamping force on the cable (11) as a function of the jaw rotation.

9. System according to claim 8, wherein such intermediate kinematic mechanism is obtained with an upper pin (717) in which two connecting rods converge (714,715) which connect the elastic system (75) respectively to the jaw (71) through the pin (73) and to the fixed body (76) through the pin (716).

10. System according to claim 9, wherein such intermediate kinematic mechanism is obtained by substituting the connecting rod (714) or the connecting rod (715) or both with a sliding or rolling surface by direct contact (718), which accomplishes the same function as the connecting rod itself.

11. System according to claim 1, wherein the running cable enters between the jaws from the upper side.

12. System according to claim 1, wherein such trolley comprises a fixed frame to which four equalisers (2) are connected, each with two carrying wheels (1) for the support on the carrying cable (12), two symmetric-driving vices (7) for the connection with the running cable (11), four auxiliary wheels (10) for the transit on the curved station rails.

13. System according to claim 12, wherein the rigid frame (3) is formed by two longitudinal members (4), two external crossbars (5) and four internal crossbars (6), the external crossbars being placed in proximity with the articulations of the equalisers (2), while the internal crossbars support the mentioned vices of connection to the running cable and the binding system of the suspension arm (8).

14. System according claim 1, wherein said two vices are symmetrically arranged with respect to said suspension arm, along an axis parallel to the carrying cables.

15. System according to claim 1, wherein said vices are aligned with each other and with said external crossbars such that when the trolley lifts the running cable at the passage on the line supports, said running cable sustains most of the deflection being based on said two external crossbars, and little or no deflection on said four internal crossbars.

16. System according to claim 12, wherein the auxiliary wheels are arranged inside, between the carrying cables, at a height such that the support plane on the rails is slightly lower than the carrying cables and slightly higher than the lower side of said crossbars.

17. System according to claim 16, wherein the auxiliary wheels are equipped with flange only on the internal side towards the running cable.

18. System according to claim 1, wherein said suspension strut (17) is articulated with said suspension arm (8) with a pin (16) placed approximately at the same height as the running cable (11).

19. System according to claim 1, wherein said binding system of the suspension arm (8) to the trolley is composed of a pin (9) parallel to the running cable (11) and placed at a height slightly lower than that of said cable.

Drawing