HK1076789B - A drive system for escalators and moving walkways - Google Patents

Description

Drive system for escalators and moving walkways

Technical Field

The present invention relates to a drive system for escalators and moving walkways.

Background

As is known, escalators or moving walkways are driven indirectly or directly by means of electric motors. In the case of indirect drive, at least one gear reduction is provided, wherein if necessary a power divider can also be provided, in the region of which the components of the escalator or moving walkway can be driven together. These components are the pallet or tread belt and the balustrade, if necessary and without a separate drive being provided for it. Usually, the pallet or tread belt is moved by means of a plate chain, the direction of movement of which is changed in the reversal region via a reversal member in the form of a sprocket wheel arranged in the reversal region. The basic requirements for escalators and moving walkways are to enable the pallet or tread belt to be reversed without undesirable polygon effects and to achieve synchronous operation of the pallet or tread belt and the balustrade when driven together so that one component does not operate at a higher or lower speed than the other component which could otherwise cause injury to passengers.

For optimization of the driving principle, a plate chain can be used for the pallet or pallet belt, which chain also has a larger pitch, for example about 100 or about 400mm, depending on the pallet or pallet width. However, it is likely that these expected larger chain pitches will cause problems in the polygon effect during inversion and possibly in the balustrade synchronous drive.

Secondly, so-called escalators and moving walkways are well known, which are used indoors, such as in department stores and the like; and they are equipped with drive chains, wherein, due to the relatively low forces, the pallet or pedal pins, which comprise rollers cooperating with the pallet or pedals, are arranged in the respective engagement areas of the respective drive chains. However, during the reversal of a chain, particularly with a larger chain pitch, the polygon effect that exists causes various problems.

DE-a 19849236 discloses a method and a device for guiding a chain in the region of a sprocket wheel of a continuous conveying system, in particular an escalator or a moving walkway, by supplying the chain in a straight direction to the respective sprocket wheel or drive wheel, wherein after the first element of the first link of the strand chain engages the sprocket wheel or drive wheel, a continuous adaptation of the effective chain radius is achieved, while a constant speed is determined in the strand of the chain. Preferably, the sprocket or drive wheel is small, in particular in the region of its outer diameter, for receiving the chain pins, wherein at least one rail-like guide profile is placed in this region directly beside the sprocket or drive wheel.

This measure makes it possible to effectively reduce the polygon effect, but the manufacturing effort in front of the counter-rotating wheel and in the counter-rotating area is aggravated.

A similar device for guiding a continuous belt of an escalator or moving walkway is known from DE-a 0711725. In the continuous belt, the chain rollers are guided by means of a support rail with a running path and a balancing rail with a running path. At the entrance of the sprocket that reverses the continuous belt, the chain rollers run from the straight path of travel of the support rail onto the curved path of travel of the equalization rail and thence travel to a point of engagement with the sprocket. From the path of travel of the support rail to the point of tangency, the chain rollers are guided over a distance transverse to the direction of travel toward the sprocket in a direction orthogonal to the direction of travel, which has an advantageous effect on the stable travel of the continuous belt.

This particular curved shape of the connecting element will contribute even more to reducing the polygon effect. When the chain of the escalator or moving walkway is reversed by means of the chain wheel, a multilateral and rotational effect occurs, which is particularly disadvantageous for a stable operation of the escalator or moving walkway. The polygon effect is caused by the multiple edges of the chain resting on the sprockets. As the angle of rotation increases, the effective radius of the sprocket changes so that the speed of the chain fluctuates between a maximum and a minimum. When engaging the sprocket, the chain rollers and sprocket teeth have different velocities resulting in impact. The rotational effect is caused by the angular momentum transferred from the sprocket to the links and thus the platens or the pedals.

After the chain has left the sprocket, the angular momentum is temporarily retained due to the inertia of the system, resulting in a so-called curling of the chain. If a chain guide element is provided, the angular momentum is correspondingly reduced due to friction in the chain caused by the impact between the chain and the guide.

The following documents disclose chain drive devices such as those used in conventional sidewalk conveyors and the like.

US4498890 discloses, among other things, a chain drive comprising a drive chain, the direction of movement of which can be changed in its end region by means of a reversing member. Each link is plate-shaped and has rolling bodies in its connecting region. An idealised restricting guide is provided upstream and downstream of the reversing member for driving the respective plates out of their way.

GB 354169 discloses a continuous conveyor whose chain conveyors should be reversed in different planes. A guide for the chain or a roller cooperating therewith may optionally be provided. Finally, in the drive region, means for varying the initial stress of the chain may be provided between the drive and the reversing member.

From GB422184 a drive system for a conveyor is known, in which the chain, respectively the rollers cooperating therewith, are disengaged on a specially formed guide in the direction of the spherical cap in which they are received before entering the swivel member.

Finally, DE443192 discloses a drive for a long link conveyor chain. Here, an idealised restraining guide is provided before the chain enters the respective return member, which guide presents problems similar to those associated with US 4498890.

Disclosure of Invention

The object of the present invention is to provide a new drive system for escalators and moving walkways, which is particularly equipped with plate chains with a large pitch and which is capable of changing their direction of movement in the region of the reversing elements. This can be achieved both in the entry region and in the exit region of the respective drive chain.

According to one aspect of the present invention, there is provided a drive system for escalators and moving walkways comprising at least one drive motor, optionally in conjunction with a gear arrangement; at least one drive chain designed as a plate chain and provided with a pitch, wherein each bedplate or tread plate adopts at most two chain links; a reversing member for driving the chain; and a device for changing the speed of the drive chain and correspondingly its components in the entry and/or exit area in the vicinity of the respective reversing member, wherein single or several links or single or several rollers/chain rollers cooperating with the drive chain can be guided out of their direction of movement to a predeterminable extent in the area of the reversing member, so that a speed reduction/increase is achieved which overall reduces the speed variations in the entry and/or exit area of the drive chain, and the drive system comprises a guide path for guiding chain links/rollers/chain rollers on a first side of the chain, said first side being the side of the chain on which the reversing member is located; and a curvilinear table top by means of which the chain links/rollers/chain rollers are guided and which serves to guide the chain links/rollers/chain rollers from a second side of the chain opposite to the first side.

Preferably, the device consists of a guide path, which is arranged in the conveying area of the escalator or moving walkway and is arranged before the respective reversing element, seen in the direction of movement of the drive chain, in an active relationship with the device for reducing the effective chain length in the area of the guide path.

Preferably, the guide path is provided with at least one curved table surface, by means of which the chain links, respectively the rollers/chain rollers or the chain links, respectively the rollers/chain rollers can be guided upwards.

Preferably, the guide path is in an active relationship with at least one curved member, whereby the chain link, respectively the roller/chain roller or the chain links, respectively the roller/chain rollers, can be guided downwards.

Preferably, only such links, respectively such roller/chain rollers, which engage in the respective reversing member, can be guided out of their direction of movement before their engagement.

Preferably, a guide path is provided in the exit region of the at least one reversing element, by means of which the chain or the table rollers connected to the drive chain can be guided out of its direction of movement over a predeterminable distance and to a predeterminable extent.

Preferably, the guide path is provided with a profiled contour.

Preferably, the shaped profile is such that the position of the chain or table roller can be adapted according to the phase angle of the reversing member.

Preferably, the profiled contour is formed by lands which are arranged at a predeterminable mutual distance, as seen in the direction of movement of the drive chain.

Preferably, the distance of the lands is adapted to the pitch of the drive chain.

Preferably, the height of the respective table top decreases as seen in the direction of movement of the drive chain.

This object is achieved by a drive system for escalators and moving walkways, comprising at least one drive motor, optionally cooperating with a gear arrangement; at least one drive chain designed as a plate chain and provided with a pitch, wherein each bedplate or tread plate adopts at most two chain links; a reversing member for driving the chain; and a device for changing the speed of the drive chain and correspondingly its components in the entry and/or exit region in the vicinity of the respective reversing member, wherein single or several chain links or single or several rollers/chain rollers cooperating with the drive chain can be guided out of their direction of movement to a predeterminable extent in the region of the reversing member, so that a speed reduction/increase is achieved which overall reduces the speed variations in the entry and/or exit region of the drive chain.

In contrast to the state of the art, the object of the invention is to make it possible to effectively eliminate the speed difference between the drive chain and the reversing member in the entry region on the one hand and optionally in the exit region on the other hand, in that the single or several chain links, respectively at least one roller or chain roller of the drive chain, are moved out of their direction of movement before entering the reversing member or after leaving the reversing member, which is preferably designed as a sprocket. The entry/exit area cannot be considered as a point, but it covers a certain area-depending on the chain pitch-either in front of or behind the respective reversing member.

Depending on the sprocket phase, the speed is affected by the change in radius. The desired constant speed is thus corrected. In the case of chain drives for escalators and moving walkways, the chain is generally guided through a path that has an almost constant curve shape in the current state of the art before entering the sprocket.

The present invention takes advantage of the fact that the position of the upstream link/chain roller or roller as a function of sprocket phase can be influenced. In these positions, where higher speeds are geometrically caused by chain engagement, one or several of the mentioned chain links, respectively rollers or chain rollers, will be influenced by the curve shape of the upstream or downstream path, so that a speed reduction/increase is achieved, which overall reduces the speed variations in the entry/exit area of the drive chain. At the same time, a balancing of the polygon effect is achieved, since the speed regulation is no longer felt as a collision by the user of the escalator or moving walkway. The safe operation and the service life of the components of the escalator or moving walkway can be significantly increased. The polygon effect, caused by the larger chain pitch of the pallet or tread chain and having a negative influence on the counter-rotating member designed as a sprocket and optionally on the handrail wheel, is almost eliminated by the subject matter of the present invention. The economically positive effect of a larger chain pitch (lower chain price) can thus be effectively integrated into existing drive systems.

The chain pitch, which is in fact in line with the current state of the art, is achieved with 3 links of about 133mm per pallet or tread for a typical pallet or tread length of about 400 mm. The number of teeth on the periphery of the respective reversing element is adapted thereto, for example by Z17, but it can also vary depending on the diameter of the respective reversing element. Due to the high elasticity of the drive chain, the polygon effect can be practically ignored in determining the chain size if z ≧ 19 and if a smaller pitch is set at higher speeds. However, the z < 17 sprocket should be provided only for manual operation or only for a slow running chain.

The chain pitch can in principle be increased in two steps. Another possible chain pitch under the same conditions (approximately 400mm of tread length of the pallet or tread) may be 200mm on the one hand and 400mm on the other hand, i.e. two links per pallet or tread or one link per pallet or tread. The respective tooth numbers of the counter-rotating members used, in particular of the sprockets, are in this case approximately z-12 or z-6 (depending on the diameter of the counter-rotating members).

The subject matter of the invention can in principle be used for all types of escalators or moving walkways, but is preferably used for the drive chain of escalators or moving walkways which can be used inside buildings. Thus, not only the effect of a larger chain pitch, but also the combination of this effect with appropriate measures to reduce the polygon effect, results in an economically advantageous solution, in particular for drive arrangements for department store escalators and moving walkways.

Drawings

The subject matter of the invention is illustrated in the drawings and described below with the aid of exemplary embodiments. Wherein:

fig. 1 is a diagrammatic illustration of a drive chain reversing area of an escalator;

FIG. 2 is a schematic, diagrammatic view of a drive system according to the present invention with respect to a drive chain entry region;

FIG. 3 is an enlarged view of the area where the drive chain enters the reversing member;

fig. 4 is a diagrammatic illustration of the guide path in the exit area of the drive chain.

Detailed Description

Fig. 1 shows the reversing area of an escalator, which is only schematically shown. The drive chain 1 is shown as a plate chain and in this embodiment comprises a number of chain rollers, the direction of movement of which changes in the direction indicated by the arrow, while being located in respective grooves 3 of a reversing element 4 designed as a sprocket. When engaging the sprocket, the chain rollers 2 and the sprocket 4 teeth have different speeds to cause impact. The rotational effect is caused by the angular momentum transferred from the sprocket 4 to the chain links and thus to the escalator platens (not shown). After the drive chain 1 has disengaged from the sprocket 4, this angular momentum is temporarily retained due to the inertia of the system, resulting in a so-called curling (curling) of the drive chain 1.

This is symbolically characterized by the arrows going up and down. This angular momentum is reduced by the friction in the drive chain 1, in particular the impact between the drive chain 1 and the guide, if a chain guide element is provided. Such impacts are perceptible as noise, which may irritate the user of the escalator, since he cannot specifically identify the noise.

Fig. 2 is a diagrammatic schematic view of a drive system according to the invention, which can be used for example in an escalator. Only the main parts, such as the plate chain 1 comprising the chain rollers 2, and the reversing element 4, which is designed as a sprocket and comprises the guide grooves 5 for the chain rollers 2, are shown. According to the invention, a guide path 6 is provided before the chain roller 2 enters the reversing member 4, which guide path is provided with a curved table top 7 in this example. Since the direction of movement of the chain roller 2 is changed in the upward direction in the region of the curved land 7, the chain is shortened in this region, and a change in speed (V ═ non-constant) is obtained in this region. The phase before and after the chain roller(s) 2 have entered the reversing member 4 is specified. The subject of the invention makes use of the fact that the position of the upstream chain roller 2 as a function of the phase of the reversing member 4 can be influenced. At such a position, in which the higher speed is geometrically predetermined by the chain engagement, at least one chain roller 2 will be influenced in its position by the curved table 7 of the guide path 6, so that a speed reduction or increase is obtained, which overall reduces the speed variation in the entry region 8 and thus the polygon effect (polygon effect).

Fig. 3 illustrates another possibility to influence the speed of the drive chain 1 'also comprising chain rollers 2'. The figure shows a sprocket 4 'with guide grooves 5' for the chain rollers 2 'driving the chain 1'. The chain rollers 2 'are guided on a guide path 6' arranged in the entry region of the drive chain 1 'in a linear direction towards the reversing member 4'. Between the guide path 6 'and the reversing element 4', a curve-like means 7 'is provided, by means of which the chain roller 2' is dropped down from the direction of linear movement and thus precisely engages in the guide groove 5 'in the entry region 8'. This method of reducing the polygon effect can be used for both the drive chain 1' having a chain pitch of 133mm (the number of teeth of the reversing member is 17) and the chain pitch of P-200 mm (Z-12). It is economically advantageous for chain pitches greater than 133mm due to reduced chain cost.

In fig. 4, the guide path 6 "is shown mainly in the exit area of the reversing member of the drive chain 1, which takes the position of the chain roller 2 as the phase angle of the sprocket 4And adapted accordingly so that a noise reduction is obtained. For this purpose, the table tops 9, which are dependent on the chain pitch, are arranged at a predeterminable distance 1 in the region of the guide path 6 ″. The height h of each table 9 is the phase angle of the chain wheel 4And simulates the upward and downward movement of the drive chain 1, the latter being caused by the curling of the drive chain 1 in the exit region. The height h of the individual table tops 9 can be different, depending on the angular momentum to be reduced and seen in the direction of movement of the drive chain 1, i.e. it can optionally be reduced in the direction of movement of the drive chain 1. The distance 1' of the individual table tops 9 is adapted to the respective chain pitch of the drive chain used.

Claims (11)

1. A drive system for escalators and moving walkways comprising at least one drive motor, optionally in conjunction with a gear arrangement; at least one drive chain (1, 1') designed as a plate chain and provided with a pitch, wherein each plate or tread plate uses at most two chain links; a reversing member (4) for driving the chain (1); and a device (7, 7 ', 9) for varying the speed of the drive chain (1, 1') and correspondingly of the parts (2) thereof in an entry and/or exit region in the vicinity of the respective reversing member (4), wherein single or several chain links or single or several rollers/chain rollers cooperating with the drive chains (1, 1') can be guided out of their direction of movement to a predeterminable extent in the region of the reversing element (4) so that a speed reduction/increase is achieved, which overall reduces the speed variations of the drive chains (1, 1') in and/or out of the area, and the drive system comprises a guide path (6') on a first side of the chain, which first side is the side of the chain on which the reversing member is located, guiding the chain links/rollers/chain rollers; and a curved table top (7 ') by means of which the chain links/rollers/chain rollers are guided (7 '), and which curved table top (7 ') serves to guide the chain links/rollers/chain rollers from a second side of the chain, opposite to the first side.

2. Drive system according to claim 1, characterized in that the means are formed by a guide path (6, 6 ', 6 ") arranged in the conveying area of the escalator or moving walkway and arranged before the respective reversing element (4, 4 ') seen in the direction of movement of the drive chain (1, 1 ') in functional relationship with means (7, 7 ', 9) for reducing the effective chain length in the area of the guide path (6, 6 ', 6").

3. Drive system according to claim 1 or 2, characterized in that the guide path (6, 6 ") is provided with at least one curved table (7, 9) by means of which the chain links, respectively the roller/chain roller (2) or the chain links, respectively the roller/chain roller (2) can be guided upwards.

4. Drive system according to claim 1 or 2, characterized in that the guide path (6 ') is in an active relationship with at least one curved member (7'), whereby the chain link, respectively the roller/chain roller (2) or the chain link, respectively the roller/chain roller (2) can be guided downwards.

5. Drive system according to claim 1 or 2, characterized in that only such chain links engaging in the respective reversing member (4 '), respectively such roller/chain roller (2'), can be guided out of its direction of movement before their engagement.

6. Drive system according to claim 1 or 2, characterized in that a guide path (6 ") is provided in the exit region of the at least one reversing element (4), by means of which the chain or the table rollers (2) connected to the drive chain (1) can be guided out of its direction of movement over a predeterminable distance (L) and to a predeterminable extent (h).

7. Drive system according to claim 1 or 2, characterized in that the guide path (6 ") is provided with a profiled contour (9).

8. A drive system according to claim 7, characterised in that the profile (9) is shaped so as to be dependent on the phase angle (C) of the reversing element (4)) To adapt the position of the chain or table rollers (2).

9. Drive system according to claim 7, characterized in that the profiled contour (9) is formed by table tops which are arranged at a predeterminable mutual distance (1') as seen in the direction of movement of the drive chain (1).

10. Drive system according to claim 1 or 2, characterized in that the distance (1') of the tables (9) is adapted to the pitch of the drive chain (1).

11. Drive system according to claim 1 or 2, characterized in that the height (h) of the table tops decreases as seen in the direction of movement of the drive chain (1).