Patent Grant
11691654
The present invention relates to a cableway carriage.
Cableway carriages are used for the yarding of cut lumber. Cableway carriages include the type that performs carriage by way of aerial lifting (Patent Literature 1) and the type that performs carriage through skidding (Patent Literature 2). In the case of the type that performs carriage through skidding, a cableway carriage of the so-called single-drum type, where the carriage is made to move using a single winch, is subject to the following problems.
For example, when lifting a load, there is the problem that the cableway carriage then moves in the direction in which the wire rope is pulled before the end of the lumber rises. When the cableway carriage moves thus in the driven direction, it becomes difficult for a force to act in the direction in which the end of the lumber is made to float, and when there is an obstacle such as a rock or a stump in particular, the problem then arises that the lumber can no longer be moved without getting past the obstacle. When the wire rope is pulled forcibly using a winch starting from this state, the tensile force is then high, and hence there is the problem that when this tensile force exceeds the obstacle, the lumber suddenly flies from the obstacle, which is extremely dangerous.
Meanwhile, lowering a load constitutes a further problem in that, because the cableway itself is on a descending slope, the carriage vigorously slips downward under the weight of the cableway carriage itself and due to the pulling by the winch, which is dangerous, and there is the problem that the end of the lumber does not rise. Furthermore, due to the inclined surface, there is the problem that the lumber slipping downward ahead of the carriage also represents a danger. The steeper the surface, the more dangerous the resulting situation. For this reason, a single-drum cableway carriage has conventionally been unsuitable for use in lowering a load.
The present invention was conceived in view of such problems, and an object of the present invention is to provide a single-drum-type cableway carriage that can also be safely used without danger for lumber-yarding which involves either the raising of a load or the lowering of a load over gentle slopes and steep surfaces.
The present invention adopts the following means to achieve the foregoing object.
A cableway carriage according to the present invention is a cableway carriage for carrying a load by utilizing a cableway that has a main cable, and a rope including a trigger, the cableway carriage including:
a base member;
a main cable braking member that has a braking face that comes into contact with the main cable and that is secured to the base member;
a first lever that has a first fulcrum serving as a center of rotation and secured to the base member, a first lever braking face provided in a position facing the braking face, a biasing member that biases the first lever braking face in a direction of separation from the braking face, and a drive pulley capable of applying a force in the direction in which the first lever braking face is brought close to the braking face by the tensile force of the rope, and
a second lever that has a second fulcrum secured to the base member and serving as a center of rotation, and a first lever pressing part capable of pressing the first lever in the direction in which the first lever braking face is separated from the braking face,
wherein, when the trigger, which indicates that the load has reached a predetermined height, presses the second lever, the second lever causes the first lever to separate the first lever braking face from the braking face.
In the case of the cableway carriage according to the present invention, basically, when a tensile force due to a load is being applied to the rope, as long as the first lever braking face of the first lever is not separated from the braking face as a result of the trigger pressing the second lever upward, that is, as long as an optimal state for lifting and carrying the load has not been assumed, there is no movement of the cableway carriage, thus affording the cableway carriage superior safety and enabling same to be used for either lifting a load or lowering a load. Furthermore, because the cableway carriage is immediately subjected to braking if the load undergoes an operation other than the intended movement caused by driving using the rope, skidding with a superior level of safety can be implemented.
Furthermore, in the cableway carriage according to the present invention, the second lever may have a surface with which the trigger comes into contact that is formed having a convex, curved surface.
By adopting this configuration, it is possible to cause the second lever to apply a force to the first lever to move the first lever braking face in the direction of separation from the braking face, irrespective of whether the direction of the tensile force of the rope due to the load is the travel direction of the cableway carriage or the direction opposite to the travel direction.
Moreover, in the cableway carriage according to the present invention, at least a portion of the second lever may be formed as two parallel plates between which the first lever is arranged in an intersecting manner.
By adopting this configuration, the likelihood of the first and second levers twisting can be reduced. Furthermore, the likelihood of the intersecting state between the first and second levers being released can be reduced.
Moreover, in the cableway carriage according to the present invention, at least a portion of the second lever may be formed as two parallel plates between which the rope is arranged.
By adopting this configuration, a trigger attached to the rope is capable of reliably pressing the second lever upward.
In addition, in the cableway carriage according to the present invention, the second lever may be configured such that a moving member for preventing the rope from disengaging from the second lever is slidably attached in the longitudinal direction of the second lever.
By adopting this configuration, the rope can be prevented from disengaging from the second lever.
Moreover, in the cableway carriage according to the present invention, the braking face may be provided to a member that is exchangeable for the main cable braking member.
By adopting this configuration, the braking face can be easily exchanged even when worn.
Moreover, in the cableway carriage according to the present invention, the first lever braking face may be provided to a member that is exchangeable for the first lever.
By adopting this configuration, the first lever braking face can be easily exchanged even when worn.
In addition, in the cableway carriage according to the present invention, below the drive pulley, a correction base pulley that, even when the rope is driven by a load in a direction opposite to the travel direction, corrects the line of the rope with respect to the drive pulley to the direction in which force is applied to the first lever in the direction in which the first lever braking face is brought close from the braking face, may be included.
By adopting this configuration, even in a case where the rope is pulled in either the travel direction or in the direction opposite to the travel direction, a force can be applied to the first lever in the direction in which the first lever braking face is brought close from the braking face, thereby enabling reliable braking.
A cableway carriage 100 according to the present invention will be described in detail in conjunction with the drawings.
The cableway carriage 100 according to the present invention uses a cableway that includes a main cable 110 that suspends the cableway carriage 100 and a rope (including wire) 120 that moves the cableway carriage 100, and is used as a single-drum type cableway carriage for controlling movement by means of a single winch. The cableway carriage 100 is particularly suitable for yarding cut lumber as a load by means of skidding.
As illustrated in
The base member 1 is formed from a highly rigid plate such as an iron plate and is a member for securing the main cable braking member 10, the first lever 20, the second lever 30, and the base pulley 41, and the like, but there are no particular limitations on the form of the base member 1.
The main cable braking member 10 is a member that is disposed adjacent to the main cable 110, and because the main cable 110 is sandwiched between the main cable braking member 10 and the first lever 20, the relative position of the cableway carriage 100 with respect to the main cable 110 is secured. In the present embodiment, a surface that includes a block-shaped mass and lies opposite the main cable 110 forms a braking face 11. The braking face 11 is disposed in a position in which a slight gap from the main cable 110 is formed, in a state enabling movement of the cableway carriage 100, that is, in a state where force from the cableway carriage 100 is not applied to the main cable 110. Because the braking face 11 comes to be worn away through abrasion, a braking face part 11a may be removably provided using a bolt or the like to the main cable braking member 10 as illustrated in
The first lever 20 is disposed on the opposite side from the main cable braking member 10, with the main cable 110 interposed therebetween, and has a function for securing the cableway carriage 100 to the main cable 110 by sandwiching the main cable 110 together with the main cable braking member 10. As illustrated in
As illustrated in
The base pulleys (41 to 44) are pulleys which are directly attached to the base member 1 and which are for guiding the main cable 110 and rope 120. The base pulleys include a first base pulley 41 and a second base pulley 42, which guide the main cable 110, a third base pulley 43 for guiding the rope 120, and a correction base pulley 44 for correcting the direction of the rope 120 with respect to the drive pulley 26. The first base pulley 41 and second base pulley 42 are pulleys for suspending the cableway carriage 100 that are arranged on both sides of the main cable braking member 10 and arranged such that the main cable 110 is slightly below the braking face 11. The third base pulley 43 is disposed to the right of the first fulcrum 21 such that the upper surface of the third base pulley 43 is above the lower surface of the first pulley 25 so that the rope 120 makes contact with the lower surface of the first pulley 25. The correction base pulley 44 is configured so that the tensile force of the rope 120 effectively acts downward with respect to the drive pulley 26 even when the rope 120 is pulled in the direction opposite to the travel direction, and is disposed such that the right side surface of the correction base pulley 44 is located substantially below the left side surface of the drive pulley 26.
Furthermore, a cover for covering the front surface is optionally provided, and a block and a pulley that guide the main cable 110 or the rope 120 may suitably also be provided.
The cableway carriage 100 constituted as above is used as follows. First, as illustrated in
When a tensile force is not acting on the rope 120 from the lumber 200 in this state, that is, in a state where the lumber 200 is not completely suspended, the first lever 20 is biased in a clockwise rotation direction by the biasing member 50. For this reason, the first lever braking face 24 is not in contact with the main cable 110 and is not in a state of braking the main cable 110. Hence, the cableway carriage 100 is capable of moving freely along the main cable 110.
When the rope 120 is driven from this state and a lifting force is applied to the lumber 200 by the rope 120, the weight W of the lumber 200 then exerts a tensile force T on the rope 120. In this case, weight W=tensile force T. The drive pulley 26 applies a downward force due to the tensile force T applied to the rope 120 and, as indicated by the arrow in
When the rope 120 is also driven from this state, the cableway carriage 100 is secured to the main cable 110, and hence the load can be lifted up in a state where the position of the cableway carriage 100 on the main cable 110 is secured rather than the cableway carriage 100 being pulled along as per the prior art.
Furthermore, when the rope 120 is driven from this state, the second lever 30 is then rotated clockwise, as illustrated in
The relationships between the forces at such time are as follows. As illustrated in
T: the tensile force acting on the rope 120
F: the force with which the second lever 30 is rotated counterclockwise by the trigger 60
H: the drag at the point of contact between the first lever 20 and the second lever 30
a: the distance between the first fulcrum 21 and the point of application of the drive pulley 26
b: the distance between the first fulcrum 21 and the point of application which is the point of contact between the first lever 20 and the second lever 30
c: the distance between the second fulcrum and the point of application which is the point of contact between the first lever 20 and the second lever 30
d: the distance between the second fulcrum and the point of application which is the point of contact between the trigger 60 and the second lever 30
α: the angle between a and the main cable
β: the angle between b and the main cable
γ: the angle between c and the main cable, and
δ: the angle between d and the main cable,
the balance equation for the vertical component of the rotational moment of the first lever 20 is
T·α·cos α=H·b·cos β,
Therefore, the relationship between tensile force T of the rope 120 and the upward pressing force F of the trigger 60 at a braking release starting point P at which, when the rope 120 is driven, the trigger 60 causes the second lever 30 to rotate clockwise and the first lever 20 is made to rotate clockwise via the first lever pressing part 32 (a position in which there is no longer a pressing force from the first lever pressing part 32 due to the pressing force on the second lever 30 from the trigger 60, thereby enabling free movement on the rope; see
F=(a·cos α×c·cos γ)/(b·cos β×d·cos δ)
Thus, when a force exceeding the sum (W+F) of the weight W of the lumber 200 and the upward pressing force F of the trigger 60 is applied to the rope 120, the second lever 30 exceeds the braking release starting point and rises, and the first lever 20 rotates clockwise so as to release the braking face, thereby enabling free movement.
Note that, when a<b at the first lever 20 and c<d at the second lever 30, F can be a smaller force than W. However, α, β, γ, and δ vary according to the rotation of the first lever 20 and second lever 30, and hence, within the range of motion of both levers, it is important that β and γ on the long side be 90° or less.
During movement, when lifting a load, the cableway carriage 100 itself basically does not rise due to its own weight, and the lumber 200 also travels at a lag to the cableway carriage 100, and therefore motion according to the foregoing principles readily occurs.
In contrast, when lowering a load, the main cable 110 may slip downward by the distance that the rope 120 is driven or more due to the weight of the cableway carriage 100 itself. When the cableway carriage 100 slips downward, because the cableway carriage 100 is then ahead of the movement of the lumber 200, the trigger 60 then drops below the braking release starting point. Hence, the first lever 20 is no longer subject to the pressing force from the second lever 30 and rotates counterclockwise due to the action of a tensile force. Thus, the cableway carriage 100 is subjected to braking and the braking action comes into effect due to its slight slip downward. As a result of experimentation, it is ascertainable that braking generally comes into effect at about 10 to 20 cm. When, as mentioned earlier, the rope 120 is continuously driven starting from this braking state, the lumber 200 is pulled once again, and due to the trigger 60, the second lever 30 reaches the braking release starting point, thereby enabling the cableway carriage 100 to move as a load.
Furthermore, whether a load is being lifted or lowered, when a strong tensile force on the rope 120 is maintained at the moment an obstacle is exceeded, and when lowering is performed over a temporary steep surface, and so forth, the lumber 200 may fly ahead of the cableway carriage 100. Under such circumstances, the following operations ensue. When the lumber 200 is ahead of the cableway carriage 100, the rope 120 is pulled strongly. Hence, the first lever 20 is no longer subject to the pressing force from the second lever 30 and rotates counterclockwise due to the action of a tensile force. Thus, the cableway carriage 100 is subjected to braking and is secured. Therefore, the advancement of the lumber 200 suddenly stops and advancement is prevented beyond a certain point. Accordingly, because the lumber 200 is greatly prevented from advancing, the lumber 200 can be safely carried. Starting from this state, the lumber 200 is driven and braking is released by the trigger 60, thereby restarting movement.
After such carriage of the lumber 200 to the intended destination has ended, an unloading operation ensues as follows. The lumber 200 reaches the destination, the driving of the rope 120 is stopped, and when the lumber 200 drops slightly, the trigger 60 drops below the braking release starting point and the cableway carriage 100 is subjected to braking. When the tensile force on the rope 120 is relaxed in this state, the lumber 200 then drops to the degree that the tensile force is relaxed. Therefore, when the lumber 200 drops, unloading can be performed safely while the cableway carriage 100 remains secured.
In the case of the cableway carriage 100 according to the present invention, the weight of the load is likely applied from a direction other than a vertically downward direction at each stage, namely, loading, yarding movement, and unloading. However, when there is a load in the travel direction from a vertically downward direction, a force is reliably applied in a counterclockwise direction to the drive pulley 26 of the first lever 20, as illustrated in
However, when there is a load in the direction opposite to the travel direction from a vertically downward direction, because the drive pulley 26 is then pulled in a vertically downward direction by the correction base pulley 44 as illustrated in
As mentioned earlier, with the cableway carriage 100 according to the present invention, because the cableway carriage 100 can be prevented from dropping due to its own weight not only when a load is lifted but even when a load is lowered, same can also be suitably used for lowering a load.
Furthermore, even when a load suddenly flies in the travel direction or a load slips due to a steep slope, the cableway carriage 100 is subjected to braking, thereby enabling a load to be carried more safely.
Furthermore, the cableway carriage 100 according to the present invention has a disengagement prevention mechanism for the rope 120, and it is therefore possible, in a state where the cableway carriage 100 is secured, to also intercept a load in a horizontal direction other than the travel direction of the cableway carriage 100, that is, when the load is not under the main cable 110 line. In particular, because a load can be intercepted in the position in which the cableway carriage 100 is secured, by securing the cableway carriage 100 in the position desired for interception, carriage to substantially below the cableway carriage 100, which is in a preferable position, can be suitably performed.
Note that the present invention is not limited to or by the configurations of the embodiment, rather, changes may suitably be made within a scope not departing from the spirit of the present invention.
Although a case where lumber 200 is used as the load is described in the foregoing embodiment, a load other than lumber may also be used. The present invention may also be used for aerial carriage.
Furthermore, as illustrated in
As illustrated in the foregoing embodiment, the present invention can be utilized as a carrying tool for lumber and can be used for carrying loads in the fields of civil engineering, architecture, warehousing, and transportation.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2018-048911 | Mar 2018 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2019/005838 | 2/18/2019 | WO |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2019/176456 | 9/19/2019 | WO | A |
| Number | Name | Date | Kind |
|---|---|---|---|
| 690660 | Ney | Jan 1902 | A |
| 1599456 | Burks | Sep 1926 | A |
| 4125919 | Dumont | Nov 1978 | A |
| 4238038 | Fikse | Dec 1980 | A |
| 8333155 | Cylvick | Dec 2012 | B2 |
| 8708109 | Steele | Apr 2014 | B2 |
| 10023208 | Brown | Jul 2018 | B2 |
| Number | Date | Country |
|---|---|---|
| 396918 | Nov 1993 | AT |
| 103818830 | May 2014 | CN |
| 203740909 | Jul 2014 | CN |
| 233277 | Feb 1986 | DE |
| 10229554 | Jan 2004 | DE |
| 0262372 | Apr 1988 | EP |
| Number | Date | Country | |
|---|---|---|---|
| 20210039690 A1 | Feb 2021 | US |
