CN220052964U - Device for damping strips of variable length in a ring between two tyre building stations - Google Patents

Abstract

The utility model relates to a device for buffering strips of variable length in a ring between two tire building stations, wherein the device comprises a infeed conveyor and a outfeed conveyor, respectively, defining a pit for receiving the ring, wherein the pit extends in a pit plane, wherein the infeed conveyor and the outfeed conveyor form a gap between an entrance side and an exit side, wherein the device is provided with a ring guide, wherein the ring guide comprises a guide rod which extends transversely to the pit plane through the gap and is freely movable in a vertical direction parallel to the pit plane, wherein the guide rod extends along a guide rod axis, wherein the guide rod is freely movable in an inclined range about an inclined axis perpendicular to the guide rod axis and to the vertical direction.

Description

Device for damping strips of variable length in a ring between two tyre building stations

Technical Field

The present utility model relates to a device for damping strips of variable length in a loop between two tyre building stations.

Background

NL 1020097c 2 discloses a device for tire building. The device forms a loop for buffering intermittent variations in the speed of the strip between the two stations. The device is provided with a first conveyor belt and a second conveyor belt arranged in a V-shape for supporting the strip on both sides of the loop. The device is also provided with a magnet for gently attracting the strip to the conveyor belt as it passes through the loop. The device is placed at least partially underground in a pit. Thus, the apparatus is called a pit conveyor.

Disclosure of Invention

A disadvantage of the known device as disclosed in NL 1020097c 2 is that the conveyor belts are spaced apart, so that no continuous support surface is formed in the bottom part of the loop in the transition from the first conveyor belt to the second conveyor belt. In other words, the strip is unsupported in said bottom part of the loop in the gap between the conveyor belts. When the strip is first guided through the loop, it must be manually lifted across the gap between the first and second conveyor belts, and it needs to be manually held on the second conveyor belt until there is sufficient friction between the strip and the second conveyor belt to prevent the strip from slipping back into the loop.

Moreover, when the known device is in use, the behavior of the strip in the gap between the conveyor belts may not be predictable. Thus, as the strip is further conveyed by the second conveyor belt, the strip may not align and/or be deformed. In particular, the strip may start to swing in a lateral direction. More particularly, when cushioning a strip in which the reinforcing cords are embedded in the body of the strip at an inclined cord angle, such as in a cushioning layer, uneven tension in the strip may cause the strip to swing primarily toward one side.

It is an object of the present utility model to provide a device for a variable length strip in a loop buffered between two tyre building stations, wherein the strip can pass through the loop more uniformly and/or without human intervention.

The utility model provides a device for a strip of variable length in a loop buffered between two tire building stations, wherein the device comprises an infeed conveyor and an outfeed conveyor defining an infeed side and an outfeed side, respectively, for receiving a pit of the loop, wherein the pit extends in a pit plane, wherein the infeed conveyor and the outfeed conveyor are at least partially spaced apart in a horizontal direction parallel to the pit plane to form a gap between the infeed side and the outfeed side, wherein the device is provided with a loop guide between the infeed conveyor and the outfeed conveyor for guiding said strip through said loop in said gap, wherein the loop guide comprises a guide rod extending transversely to the pit plane through the gap and being freely movable in a vertical direction parallel to the pit plane within a guiding range, wherein the guide rod extends along a guide rod axis, wherein the guide rod is freely movable about a tilting axis perpendicular to the guide rod axis and to the vertical direction within a tilting range.

The guide rods may be positioned inside the ring at the gap to nest in the strip in the bottom portion of the ring, rest on the strip, and/or freely follow the strip. The weight, orientation and/or freedom of movement of the guide bar when resting on the straps in the loop may reduce, correct, dampen and/or limit any misalignment and/or wobble of the straps. Thus, the strap may pass through the loop, and more particularly, through the gap, more evenly and/or without human intervention. In particular, the strips may be transferred from the infeed conveyor to the outfeed conveyor more uniformly and/or with improved alignment.

The guide bar may adjust its orientation about the tilt axis to some extent in response to changes in the orientation of the strip on which it rests. Thus, even if the strip is slightly inclined, the guide bar can maintain optimal contact with the strip. Moreover, the tilt range may be limited to limit the tilt of the strip about said tilt axis.

In a preferred embodiment, the guide rod extends along a guide rod axis, wherein the guide rod comprises a shaft extending along the guide rod axis and a roller body mounted concentrically about the shaft and rotatable about the guide rod axis relative to the shaft. Rotation of the roller body may reduce friction between the guide bar and the strip passing along the guide bar.

In a further embodiment, the guide rod extends along a guide rod axis, which is arranged at a steering angle relative to the pit plane, wherein the steering angle is adjustable. Preferably, the steering angle is adjustable over a steering range of sixty to one hundred twenty degrees. The steering angle can be adjusted to optimally correct the strip to be deflected sideways.

In another embodiment, the ring guide further comprises a frame, wherein the guide bar is coupled to the frame and is vertically movable relative to the frame within the guide range. The frame may define a degree of freedom of movement that the guide bar has with respect to the strap.

Preferably, the guide bar extends along a guide bar axis, wherein the frame is configured for holding the guide bar, wherein the guide bar axis is at a steering angle with respect to the pit plane. Thus, the orientation of the frame relative to the strap also defines the steering angle of the guide bar axis relative to the strap.

More preferably, the ring guide further comprises a guide base for supporting the frame, wherein the frame is rotatable relative to the guide base about a steering axis extending parallel to the vertical for adjusting the steering angle. By adjusting the frame around the steering axis, the steering angle of the guide bar held by the frame can be adjusted around the same steering axis.

Most preferably, the ring guide further comprises a steering angle adjustment mechanism for adjusting and/or locking the orientation of the frame relative to the guide base. Such a mechanism may, for example, facilitate adjustment in response to a change in the strap or observed behavior of the strap. In addition, the mechanism may lock or fix the orientation, thereby preventing any further unintended adjustment of the steering angle due to the force exerted by the strap on the guide bar during use of the guide bar.

In further embodiments, the frame includes a first post (upper) and a second post on opposite sides of the pit plane, wherein the guide bar has a first distal end and a second distal end opposite the first distal end, the first distal end and the second distal end being coupled to the first post and the second post, respectively. Thus, the guide bar may be supported by and moved along the frame at both distal ends, thereby providing a more stable support for the guide bar by the frame.

Preferably, the guide bar comprises a shaft extending along a guide bar axis, wherein the guide bar further comprises a first coupling member and a second coupling member connected to the shaft at a first distal end and a second distal end, respectively, wherein the first coupling member and the second coupling member facilitate tilting of the shaft relative to the frame about a tilt axis perpendicular to the guide bar axis and vertical within a tilt range. In other words, the guide bar may tilt while remaining coupled to the frame.

In another embodiment, which can also be applied in the device independently of the loop guide, the device comprises a bridge positionable in a bridge position for bridging the gap between the infeed conveyor and the outfeed conveyor. The bridge may be used to support the strip during initial infeed of the leading end of the strip from the infeed conveyor toward the outfeed conveyor. The strip may be supported across the gap by the bridge when the leading end is fed towards the presenting conveyor. Thus, no human intervention is required to transfer the front end across the gap.

Preferably, the bridge is located vertically below the guide bar. The bridge and the guide bar may be located on opposite sides of the strap, i.e. the strap extends between the bridge and the guide bar. In other words, the guide bar may already be positioned above the strip, from where the guide bar may be lowered to a position on the strip resting at the lower part of the ring or nested in the strip.

In a further embodiment, the bridge is independently movable vertically relative to the guide bar between a bridge position and a standby position below and spaced from the ring. Thus, the bridge may be removed from under the strap while the guide bar remains in place, resting on and/or nesting in the strap at the lower portion of the ring. In this way, the bridge can be prevented from interfering with the free hanging portion of the loop.

In a further embodiment, the bridge defines a concave bridge path for the straps in the support ring to cross the gap. The strip may be deflected along the concave bridge portion from an orientation matching the infeed conveyor to an orientation matching the outfeed conveyor.

Preferably, the bridge comprises a plurality of bridge rollers that together define a concave bridge path. The bridge roller may reduce friction between the strip and the bridge as the strip passes over the bridge.

In a further embodiment, each of the infeed conveyor and the outfeed conveyor comprises an inclined section and a vertical section, wherein the inclined sections of the infeed conveyor and the outfeed conveyor are oppositely inclined, wherein the concave bridge path is tangential to the inclined sections of the infeed conveyor and the outfeed conveyor when the bridge is in the bridge position. Thus, the strip can smoothly transition from the infeed conveyor to the bridge and from the bridge to the outfeed conveyor. Thus, the risk of the strap getting stuck is less and the possibility of requiring human intervention is less.

In another embodiment, which may also be applied in the device independently of the loop guide, the device further comprises a lateral limiter at one side of the pit plane for limiting movement of the strip in a lateral direction perpendicular to the pit plane at said one side of the pit plane. As previously described, when cushioning a strip in which the reinforcing cords are embedded in the body of the strip at an inclined cord angle, such as in a cushioning layer, uneven tension in the strip may cause the strip to swing primarily toward one side. By providing a lateral limiter at said one side, oscillations due to said uneven tension in the strip may be reduced, corrected, suppressed and/or prevented.

Preferably, the lateral limiter comprises a limiter bar extending vertically beside the pit plane. The restrictor bar may physically abut the strap along one longitudinal side edge of the strap.

More preferably, the restrictor bar is rotatable about a restrictor bar axis extending in a vertical direction. By rotating the restrictor bar, friction between the strap and the restrictor bar may be reduced as the strap passes along the restrictor bar.

In further embodiments, the lateral limiter further comprises a limiter base, wherein the limiter bar is movable laterally relative to the limiter base. Different batches of strips may have different widths. Thus, the lateral position of the lateral limiter may be adjusted to accommodate different widths of the strap.

Preferably, the lateral limiter further comprises a limiter driver for driving the movement of the limiter bar in lateral direction with respect to the limiter base. Thus, the lateral position of the restrictor bar may be automatically adjusted when switching to a different width of the strip or when a previously set lateral position of the restrictor bar has proven to be suboptimal. In addition, the lateral position of the restrictor bar may be continuously adjusted in response to an edge sensor at the device or upstream/downstream of the device.

The various aspects and features described and illustrated in the specification can be applied separately whenever possible. These individual aspects may be the subject of the divisional patent application.

Drawings

The utility model will be elucidated on the basis of exemplary embodiments shown in the schematic drawings, in which:

fig. 1 and 2 show side views of an apparatus for cushioning a variable length strip in a loop, at the beginning of cushioning and during cushioning, respectively, according to an exemplary embodiment of the present utility model;

fig. 3 shows a cross-section of the device according to line III-III in fig. 2; and

fig. 4 shows an isometric view of a ring guide of the device according to fig. 1 and 2.

Detailed Description

Fig. 1 and 2 show an apparatus 1 according to an exemplary embodiment of the utility model for cushioning a strip 9 of variable length in a loop L between two tire building stations (not shown). For example, when one of the tire building stations has a continuous process (e.g., an extruder or a winding station) and the other of the tire building stations has a discontinuous process (e.g., a cutter or a splice), the strip 9 may be subjected to intermittent speed variations between the two tire building stations.

In this example, the stripe 9 is a buffer layer (buffer ply). The buffer layer comprises an elastomer or rubber body, in particular a sheet-like body, with embedded reinforcing cords, in particular steel reinforcing cords. The reinforcement cords are arranged at an inclined cord angle to the longitudinal direction of said strip 9.

As shown in fig. 1, the device 1 comprises a infeed conveyor 2 and a outfeed conveyor 3 defining an entrance side F1 and an exit side F2, respectively, of the pit V for receiving the loop L. The term "pit" relates to the shape defined by the pit V in the strip 9 as the strip 9 travels along the loop L. This does not necessarily mean that the pit V is recessed into the ground. Pit V may be located, for example, at least partially underground (i.e., below the ground level of the factory floor) or entirely above ground level. The pit V extends in a pit plane P. In this example, pit plane P is vertical or substantially vertical, or extends parallel to vertical Z. Pit plane P has a first side S1 and a second side S2 opposite to first side S1.

Each conveyor 2, 3 is provided with a wheel or pulley and an endless conveyor belt extending around said wheel or pulley. Each conveyor 2, 3 may also be provided with a holding element, such as a magnet or a vacuum cup (not shown), to attract or hold the strip 9 to or towards the respective conveyor belt. The force exerted by the holding element on the strip 9 is small enough to allow the strip 9 to separate from the conveyors 2, 3, thereby transferring the strip 9 from the infeed conveyor 2 to the outfeed conveyor 3.

Each conveyor 2, 3 further comprises an inclined section 21, 31 and a vertical section 22, 32. The inclined sections 21, 31 of the infeed conveyor 2 and the outfeed conveyor 3 are inclined inversely. In particular, the inclined sections 21, 31 are positioned in V-shaped or groove-shaped orientations to form correspondingly shaped sections of the ring L and/or the pit V. The vertical sections 22, 32 of the infeed conveyor 2 and outfeed conveyor 3 are spaced apart from each other and are parallel or substantially parallel in the vertical direction Z. Thus, the vertical sections 22, 32 define a gap G between the entrance side F1 and the exit side F2 in a horizontal direction X parallel to the pit plane P. In other words, the strip 9 is not supported by the conveyors 2, 3 in said gap G. In at least one configuration of the device 1, the bottom portion of the loop L is a free hanging portion, as shown in fig. 2.

As shown by comparing fig. 1 and 2, the length of the strips 9 in the loop L can be changed by allowing more strips 9 to accumulate in the gap G. Fig. 1 shows the device 1 at a minimum capacity (i.e. with a minimum length of the loop L), for example during initial feeding of the strip 9 into the device 1. Fig. 2 shows a device 1 with a loop L having a larger capacity and/or length for cushioning strips 9 than the minimum capacity of fig. 1.

As further shown in fig. 1, the device 1 is provided with a loop guide 4 between the infeed conveyor 2 and the outfeed conveyor 3 for guiding the strip 9 through the loop L in said gap G. As best seen in fig. 4, the ring guide 4 comprises a guide bar 41 which is freely movable in a vertical direction Z parallel to the pit plane P within a guide range R1. The guide rods 41 extend transversely or transversely to the pit plane P through the gap G. In the context of the present utility model, the term "lateral" is to be interpreted as extending at an oblique or right angle with respect to the pit plane P. In particular, the guide bar 41 extends along a guide bar axis A1 arranged at a steering angle H with respect to the pit plane P. The steering angle H may be selected within a steering range R2 of sixty to one hundred twenty degrees. In this example, the steering angle H may be adjusted within the steering range R2 in a manner that will be discussed in more detail below.

The guide bar 41 includes a shaft 42 extending along a guide bar axis A1. In this example, the guide bar 41 further comprises a roller body 43 mounted concentrically about the shaft 42 and rotatable relative to the shaft 42 about the guide bar axis A1. The guide rod 41 has a first distal end 44 and a second distal end 45 opposite the first distal end 44. The guide bar 41 further comprises a first coupling member 46 and a second coupling member 47 connected to the shaft 42 at a first distal end 44 and a second distal end 45, respectively.

As further shown in fig. 4, the ring guide 4 is provided with a frame 5 for facilitating movement of the guide bar 41 relative to the ring L. In this example, the frame 5 comprises a first upright 51 and a second upright 52 located on opposite sides of the pit plane P. The posts 51, 52 are parallel or substantially parallel to each other. The uprights 51, 52 are interconnected at the top by crossbars or crossbars 53 to give rigidity to the frame 5. One or more additional crossbars or crossbars 54 may be provided near the bottom of frame 5.

The guide rods 41 are connected to, coupled to, suspended from the frame 5 and/or supported by the frame 5. In this example, the first distal end 44 is coupled to a first post 51 and the second distal end 45 is coupled to a second post 52. In particular, the first and second coupling members 46, 47 are coupled to the first and second uprights 51, 52, respectively. The coupling has several degrees of freedom of movement to allow the guide bar 41 to move relative to the frame 5. In particular, the guide bar 41 is movable in the vertical direction Z relative to the frame 5 within the guide range R1. In addition, the guide bar 41 is free to move, rotate or tilt about a tilt axis A2 perpendicular to the guide bar axis A1 and the vertical Z within the tilt range R3. The range of inclination R3 may be relatively small relative to the horizontal, for example less than twenty degrees or less than ten degrees. The links 46, 47 may be loosely fitted around the posts 51, 52 to provide the required freedom of movement to allow for the aforementioned tilting.

As shown in fig. 4, the frame 5 is configured to hold the guide bar 41 with the guide bar axis A1 at the above-described steering angle H with respect to the pit plane P. The ring guide 4 further comprises a guide base 40 for supporting the frame 5. The frame 5 is rotatable relative to the guide base 40 about a steering axis A3 extending parallel to the vertical direction Z to adjust the steering angle H described above. In this example, the steering axis A3 coincides with the first upright 51.

The adjustment of the steering angle H may be performed manually, semi-automatically or automatically. In this example, steering angle adjustment mechanisms 48, 49 are provided for manually adjusting and/or locking the orientation of the frame 5 relative to the guide base 40. The steering angle adjustment mechanism 48, 49 may include a nut 48 and a threaded spindle 49 that engages the nut 48 to produce relative movement between the nut 48 and the threaded spindle 49 as the threaded spindle 49 rotates. However, it is obvious that many other types of mechanisms may be suitable for obtaining steering angle adjustment or steering angle locking. Alternatively, an adjustment actuator or adjustment drive may be provided to automate the adjustment.

As shown in fig. 1, the device 1 further comprises a bridge 6 positionable in a bridge position W1 for bridging the gap G between the infeed conveyor 2 and the outfeed conveyor 3. The bridge 6 is located below the guide bar 41 in the vertical direction Z. The bridge 6 is independently movable in the vertical direction Z relative to the guide bar 41 between a bridge position W1, shown in fig. 1, and a standby position W2, shown in fig. 2, which is located below and spaced from the ring L. The bridge 6 defines a concave bridge path C for supporting the strips 9 in the ring L across the gap G. In this example, the bridge 6 comprises a plurality of bridge rollers 61 that together define a concave bridge path C. Alternatively, the concave bridge path C may be defined by a conveyor belt or another suitable type of conveying element. Note that in the bridge position W1 of fig. 1, the concave bridge path C is tangential or substantially tangential to the inclined sections 21, 31 of the infeed conveyor 2 and the outfeed conveyor 3.

As shown in fig. 3, the device 1 further comprises a lateral limiter 7 at the first side S1 of the pit plane P. The lateral limiter 7 is configured for limiting the movement of the strip 9 in a lateral direction Y perpendicular to the pit plane P in a limiter position B at said first side S1 of the pit plane P. In this example, the lateral limiter 7 comprises a limiter bar 71 extending in the vertical direction Z beside the pit plane P. The limiter bar 71 is arranged for directly abutting or contacting the longitudinal side edges of the strips 9 in said limiter position B. The restrictor lever 71 is rotatable about a restrictor lever axis A4 extending in the vertical direction Z.

In this example, the lateral limiter 7 further comprises a limiter base 70 for supporting the limiter bar 71 in the limiter position B. The limiter bar 71 is movable in the lateral direction Y relative to the limiter base 70 between a limiter position B shown in solid lines in fig. 3 and an alternative limiter position C shown in broken lines in fig. 3. The restrictor lever 71 may be moved manually, semi-automatically or automatically. In this example, the lateral limiter 7 is provided with a limiter driver 72 for driving the movement of the limiter bar 71 in the lateral direction Y relative to the limiter base 70.

A method for buffering a variable length strip 9 in a loop L using the above-described device 1 will now be briefly described with reference to fig. 1 to 4.

Fig. 1 shows the situation where the strip 9 has been fed into the pit V above the infeed conveyor 2 and extends, conveys or transfers across the gap G towards the outfeed conveyor 3 to be fed from the pit V. The guide rods 41 are nested on or supported by the resting strip 9 in the inner or bottom part of the loop L. When the capacity of the device 1 varies between the situation shown in fig. 1 and the situation shown in fig. 2, the guide bar 41 is allowed to freely follow the loop L or move together with the loop L within the guiding range R1. In particular, the guide bar 41 can rest on the strip 9 under its own weight (i.e. under the influence of gravity).

As shown in fig. 4, before or during guiding, the steering angle H of the guide bar 41 can be adjusted to optimally compensate and/or correct misalignment of the strip 9 in the lateral direction Y.

In addition, as shown in fig. 1, the bridge 6 may already be positioned in the bridge position W1 to bridge the gap G between the infeed conveyor 2 and the outfeed conveyor 3 before the strip 9 is extended across the gap G between the infeed conveyor 2 and the outfeed conveyor 3. In this way the strip 9 can be extended, transported or transferred across the gap G between the infeed conveyor 2 and the outfeed conveyor 3, while the strip 9 is supported by the bridge 6. Thus, no manual intervention is required to extend the strip 9 across the gap G.

As shown in fig. 2, once the strip 9 has been extended across the gap G, the bridge 6 can be moved in the vertical direction Z from a bridge position W1 away from the strip 9 to a standby position W2 located below the loop L and spaced from the loop L.

At any time during the above-mentioned passage of the guide strip 9 through the device 1, the movement of the strip 9 in the lateral direction Y can be limited in the manner described above using the lateral limiter 7. Before or during the passage of the guide strip 9 through the gap, the limiter bar 71 can be moved in the lateral direction Y to the optimal limiter position B1, B2.

It should be understood that the above description is included to illustrate the operation of the preferred embodiments and is not intended to limit the scope of the utility model. Many variations that are apparent to those of skill in the art are still within the scope of the utility model in light of the above discussion.

In summary, the utility model relates to a device and a method for damping strips of variable length in a loop between tire building stations, wherein the device comprises a infeed conveyor and a outfeed conveyor defining a pit for receiving the loop, wherein the pit extends in a pit plane, wherein the infeed conveyor and the outfeed conveyor form a gap between an entrance side and an exit side, wherein the device is provided with a loop guide, wherein the loop guide comprises a guide bar extending transversely to the pit plane through the gap and being freely movable in a vertical direction parallel to the pit plane, wherein the guide bar extends along a guide bar axis, wherein the guide bar is freely movable in a tilting range about a tilting axis perpendicular to the guide bar axis and to the vertical direction.

List of reference numerals:

1, a device;

2 feeding the conveyor;

21 inclined sections;

22 vertical sections;

3 gives the conveyor;

31 an inclined section;

32 vertical sections;

a 4-ring guide;

40 guiding the base;

41 guide rods;

42 shafts;

43 roller body;

44 a first distal end;

45 a second distal end;

46 a first coupling;

47 a second coupling member;

49 steering angle adjustment mechanism;

5, a frame;

51 a first upright;

52 a second upright;

53 beams;

54 cross beams;

a 6-bridge;

61 bridge rolls;

7 a lateral limiter;

70 a restrictor base;

71 a restrictor lever;

72 limiter driver;

9 strips;

a1, a guide rod axis;

a2 tilt axis;

a3 a steering axis;

a4 restrictor lever axis;

b1 limiter position;

b2 alternative limiter position;

c a concave bridge path;

f1 entrance flanks;

f2 off the side;

g gap;

h steering angle;

an L ring;

a P pit plane;

r1 guide range;

r2 steering range;

r3 tilt range;

s1, a first side;

s2 a second side;

v pit;

w1 bridge position;

a W2 standby position;

x is horizontal;

y side direction;

z is vertical.

Claims (10)

1. An apparatus for buffering strips of variable length in a loop between two tyre building stations, characterized in that the apparatus comprises an infeed conveyor and an outfeed conveyor defining an infeed side and an outfeed side, respectively, for receiving a pit of the loop, wherein the pit extends in a pit plane, wherein the infeed conveyor and the outfeed conveyor are at least partially spaced apart in a horizontal direction parallel to the pit plane to form a gap between the infeed side and the outfeed side, wherein the apparatus is provided with a loop guide between the infeed conveyor and the outfeed conveyor for guiding the strips through the loop in the gap, wherein the loop guide comprises a guide rod extending transversely to the pit plane through the gap and being free to move in a vertical direction parallel to the pit plane within a guiding range, wherein the guide rod extends along a guide rod axis, wherein the guide rod is free to move about a tilting axis perpendicular to the guide rod axis and the vertical tilting axis within a tilting range.

2. The apparatus of claim 1, wherein the guide rod extends along a guide rod axis, wherein the guide rod includes a shaft extending along the guide rod axis and a roller mounted concentrically about the shaft and rotatable relative to the shaft about the guide rod axis.

3. The device of claim 1, wherein the guide rod extends along a guide rod axis, the guide rod axis being disposed at a steering angle relative to the pit plane, wherein the steering angle is adjustable.

4. A device according to claim 3, wherein the steering angle is adjustable over a steering range of sixty to one hundred twenty degrees.

5. The apparatus of claim 1, wherein the loop guide further comprises a frame, wherein the guide bar is coupled to the frame and movable in the vertical direction relative to the frame within the guide range.

6. The apparatus of claim 5, wherein the guide rod extends along a guide rod axis, wherein the frame is configured to hold the guide rod, wherein the guide rod axis is at a steering angle relative to the pit plane.

7. The apparatus of claim 6, wherein the ring guide further comprises a guide base for supporting the frame, wherein the frame is rotatable relative to the guide base about a steering axis extending parallel to the vertical to adjust the steering angle.

8. The apparatus of claim 7, wherein the ring guide further comprises a steering angle adjustment mechanism for adjusting or locking an orientation of the frame relative to the guide base.

9. The apparatus of claim 5, wherein the frame comprises a first post and a second post on opposite sides of the pit plane, wherein the guide rod has a first distal end and a second distal end opposite the first distal end, the first distal end and the second distal end being coupled to the first post and the second post, respectively.

10. The device of claim 9, wherein the guide bar comprises a shaft extending along the guide bar axis, wherein the guide bar further comprises first and second coupling members connected to the shaft at the first and second distal ends, respectively, wherein the first and second coupling members facilitate tilting of the shaft relative to the frame about tilt axes perpendicular to the guide bar axis and the vertical tilt axis over a range of tilt.