JP7724507B2 - Winch device - Google Patents

Description

The present invention relates to a winch device.

Conventionally, forklifts are known that unload cargo from the floor of a transport vehicle, such as a truck, by using a winch device to pull the cargo from the rear end (tail) of the bed. Note that "transport vehicle" refers not only to transport vehicles such as trucks, but also to other devices with a bed on which cargo can be placed, such as ships and containers, and includes devices on which unloading operations can be performed. In Patent Document 1, a forklift's original forks are fitted with a backrest (frame), and a winch attached to the backrest of the fork is used to pull cargo from the bed toward the driver's seat.

Japanese Patent Application Laid-Open No. 2002-167191

However, in the case of Patent Document 1, in order to attach the winch, a sheath fork and a backrest for the sheath fork are required in addition to the fork and backrest that are originally provided by the forklift. This creates the problem of complicated installation and removal procedures.

Furthermore, Patent Document 1 only discloses a configuration in which the driving means of the towing device is integrated adjacent to the winch drum (see paragraph 0015 and Figure 3 of Patent Document 1). This configuration leaves no space for the operator to operate the handle of a manual winch, posing the problem that inexpensive manual winches cannot be used.

Furthermore, the configuration in Patent Document 1 only discloses a configuration that uses a single towing device (see Figure 3 of Patent Document 1). With this configuration, all towing force is concentrated on a single towing rope, and the weight of luggage that can be towed is determined by the strength of that single towing rope, resulting in the problem of requiring a strong towing rope. Another inconvenience is that it is not possible to simultaneously tow multiple pieces of luggage that are not arranged in a single horizontal row on the loading platform in a balanced manner.

An object of the present invention is to provide a winch device that has a simple structure and is attached to a forklift, allowing a load to be easily pulled out from a loading platform manually .

The winch device of the present invention is equipped with a manual or electric drive unit attached to a backrest that moves up and down along the mast of a forklift together with the forks and is positioned outside one end of the backrest in the width direction, and a spool attached to the backrest, to which rotational force is transmitted from the drive unit, winding up a towing member and towing a load connected to the towing member.

This invention provides a winch device that can be attached to a forklift and has a simple structure that allows cargo to be easily pulled from the loading platform either manually or electrically.

1 is a perspective view illustrating a configuration of a winch device according to an embodiment of the present invention. 1 is a plan view illustrating a configuration of a winch device according to an embodiment of the present invention. 1 is a front view illustrating a configuration of a winch device according to an embodiment of the present invention. 10A and 10B are cross-sectional views illustrating a method of fixing a spool and a pulling member according to another example of the spool of the winch device according to the present embodiment. 10A and 10B are plan views illustrating other modes for attaching the bearing used in the winch device according to the present embodiment to the backrest. 10A and 10B are side views illustrating another embodiment for attaching the bearing used in the winch device according to the present embodiment to the backrest. FIG. 1 is a side view illustrating a method for unloading using a winch device according to the present embodiment (part 1). FIG. 10 is a side view (part 2) illustrating a method for unloading using the winch device according to the present embodiment. FIG. 10 is a side view (part 3) illustrating a method for unloading cargo using the winch device according to the present embodiment. FIG. 10 is a plan view illustrating the configuration of a winch device according to a modified example. FIG. 10 is a front view illustrating the configuration of a winch device according to a modified example. FIG. 10 is a cross-sectional view illustrating a mounting fixture for supporting a winch of a winch device according to a modified example.

One embodiment of the present invention will now be described with reference to Figures 1 to 12. Note that all drawings used in the following description are schematic, and the dimensional relationships and ratios of elements shown in the drawings do not necessarily correspond to the actual ones. Furthermore, the dimensional relationships and ratios of elements between multiple drawings do not necessarily correspond to the actual ones. Furthermore, unless otherwise specified in the specification, each element is not limited to one, and multiple elements may be present. Furthermore, substantially identical elements are designated by the same reference numerals in the drawings, and redundant explanations in the specification will be omitted.

<Structure of the winch device>
As shown in Figures 1 and 2, the winch device 10 according to this embodiment includes, as its components, a manual handle type drive unit 20, a rotating shaft 12, a housing 14, a spool 28 (also called a drum), a reducer 18, a pulling member 22, and a transmission shaft 26. However, the present invention is not limited to this, and the reducer may be omitted for applications requiring a relatively small pulling force. The manual handle type drive unit 20 is a source of pulling power. The rotating shaft 12 is an input unit for the pulling power.

In this embodiment, the winch 11 includes, as its components, a housing 14 that protects and mounts the components; a reducer 18 that uses a combination of gears to reduce the rotational speed of the rotating shaft 12 and amplify and output the rotational torque; a transmission shaft 26 that is connected to the output shaft of the reducer 18 via a shaft coupling (not shown) and transmits the rotational torque to the spool 28; and a spool 28 that winds up the towing member 22. The winch 11 winds up the towing member 22 by fixing one end of the towing member 22 to the reeling drum 28A of the spool 28.

In this embodiment, the forklift 90 equipped with the winch device 10 is positioned near the end of the loading platform 42 of the transport device 40 on the side where the load 32 is loaded or unloaded, with the winch device 10 facing the load 32. The end of the towing member 22 of the winch device 10 that is not fixed to the hoisting drum 28A of the spool 28 is pulled out from the spool 28 and connected to a pallet 30 loaded on the loading platform upper surface 42A of the transport device 40, thereby towing the load 32 during unloading operations. Note that the use of the winch device according to the present invention is not limited to this, and a winch device attached to a forklift can also be used, for example, to pull loads placed on the floor in a factory or warehouse.

(palette)
The pallet 30 used in this embodiment is a forklift pallet with fork insertion ports. The dimensions of the pallet 30 are 1100 mm x 1100 mm x 144 mm, which is the JIS standard. However, the structure and dimensions of the pallet used with the winch device of the present invention are not limited to this and can be any as long as it can be mounted on a transportation device and can be pulled horizontally on a loading platform. For example, a sheet pallet is also possible. Furthermore, if the cargo has a handle to which a towing member can be connected, such as by tying a rope around it, the pallet may be bulk cargo that is not mounted on a pallet or the like.

Furthermore, the width along the width direction (vertical direction in Figure 2) of the loading platform 42 of the transport device 40 according to this embodiment is sufficient to line up two rows of JIS standard-sized pallets 30 side by side with ample space to spare. However, the width of the transport device that unloads using the winch device according to the present invention is not limited to this, and can be determined by the specifications of the transport device, as long as the transport device has a loading platform and end faces at the loading platform end where cargo is loaded and unloaded.

(Overall overview of the winch device)
In this embodiment, the overall size of the winch device 10 and the sizes of each of its components are shown in Fig. 1. The overall size of the winch device and the sizes of each of its components according to the present invention are not limited to this and can be set as appropriate as long as they can be attached to a forklift, but it is preferable to make them as small as possible so as not to excessively obstruct the forklift driver's field of vision or to not protrude too far from the body of the forklift, thereby compromising safety during driving.

In addition, in the present invention, the materials of the components that make up each part of the winch device may be selected appropriately, such as metal or resin, as long as they are strong enough to withstand the external forces applied when towing a load. Furthermore, the components that make up the winch device can be fastened together by any fastening method, such as screws or welding, depending on the combination of their respective materials.

(backrest)
The backrest 94 according to this embodiment is a component of the forklift 90 that is attached to the mast 92 of the forklift 90 and moves up and down along the mast together with the forks 98. The backrest 94 is a component provided to prevent the cargo 32 placed on the forks 98 from directly colliding with the mast 92 and being damaged, or from falling to the rear of the mast 92. An upper rail 96A and a lower rail 96B are provided below the backrest 94.

In this embodiment, the upper rail 96A and the lower rail 96B are considered to be components that make up the backrest 94, and all other components that move up and down in conjunction with the up and down movement of the backrest are considered to be components that make up the backrest 94. In this invention, the backrest refers to the entire part that moves up and down together with the forks. Note that while this embodiment exemplifies a case where there are two rails, the present invention is not limited to this, and the number of rails can be one or more.

As shown in Figure 3, the upper rail 96A and lower rail 96B in this embodiment protrude slightly forward of the backrest 94 and extend parallel to each other across the entire width of the backrest 94. Additionally, a single upper horizontal crosspiece 94A is provided at the top of the backrest 94, parallel to the upper rail 96A and above the upper rail 96A, across the entire width of the backrest 94, in the same plane as the frame of the backrest 94. Note that in Figure 3, components other than the winch device 10, backrest 94, and fork 98 have been omitted for clarity.

The upper rail 96A and lower rail 96B are components that engage with the raised portions of the L-shaped forks 98, thereby moving the engagement position of the forks 98 laterally and adjusting the spacing and position of the forks. In this embodiment, the upper end of the upper rail 96A in Figure 3 fits into an inverted U-shaped recess provided at the upper end of the fork raised portion 98A, thereby engaging the fork raised portion 98A with the upper rail 96A.

(Drive unit)
1 and 2, the manual handle type drive unit 20 according to this embodiment is attached to the outer surface of the housing 14, which is directly attached to the backrest 94 of the forklift 90, and is positioned outside either the left or right end in the width direction of the backrest 94. However, in the present invention, the attachment position of the drive unit is not limited to this, and for example, a housing attachment plate that protrudes forward may be attached to the frame of the backrest, a housing may be attached to the outer surface of the housing, and the drive unit may be attached to the outer surface of the housing.

The manual handle type drive unit 20 of this embodiment is a manual handle type. The manual handle of the manual handle type drive unit 20 is provided on the outer surface of the housing 14 and is attached to the other end of the rotating shaft 12, which is connected to the gear shaft of the input gear of the reducer 18 housed inside the housing 14. It is possible to drive the rotating shaft 12 and apply rotational torque by rotating around the rotating shaft 12 in a vertical plane.

In this embodiment, the manual handle type drive unit 20 is located on the outer surface of one end (lower side in FIG. 2) of the backrest 94 of the forklift 90 in the width direction (up and down direction in FIG. 2), outside the forks 98. Note that in the present invention, the drive unit may also be located on the other end (upper side in FIG. 2) of the backrest in the width direction, outside the forks. Note that in the present invention, the position on the outer surface of the backrest where the drive unit is located is not limited to the outer side of the forks in the width direction, but may also be inside the forks.

In Figure 3, the manual handle type drive unit 20 according to this embodiment is composed of a roughly cylindrical grip portion extending horizontally and a rectangular pillar-shaped arm portion standing vertically. The arm portion of the manual handle type drive unit 20 is inserted into a radial through-hole provided at the outer end (right end in Figure 3) of the rotating shaft 12, allowing it to be fixed at any position.

For this reason, the length from the grip of the arm of the manual handle drive unit 20 to the rotating shaft 12 can be adjusted as needed to apply an appropriate rotational torque to the rotating shaft 12 depending on the load of the cargo being towed. Note that, in the present invention, the shape and dimensions of the housing 14 and the manual handle drive unit 20 are not limited to these and can be set as needed.

In addition, in this embodiment, the rotational movement of the rotary shaft 12 is driven by operating the manual handle of the manual handle type drive unit 20 so as to rotate around the rotary shaft 12, but the present invention is not limited to this. For example, by providing a ratchet mechanism at the connection between the rotary shaft and the manual handle, the rotational movement of the rotary shaft can be driven intermittently in the same direction by repeatedly rotating the manual handle partially.

In this embodiment, the method of engaging the rotating shaft 12 with the arm of the manual handle drive unit 20 involves providing a radial through-hole for inserting the arm at the outer end (right end in Figure 3) of the rotating shaft 12, and providing an axial through-hole for inserting a locking pin at the apex of the outer end (right tip in Figure 3) of the rotating shaft 12, which reaches the through-hole for inserting the arm. Furthermore, multiple engagement holes are provided at intervals on the outer surface of the arm of the manual handle drive unit 20 (the surface facing the outside of the arm rectangular pillar when the grip of the manual handle drive unit 20 is extended horizontally outward as shown in Figure 3).

Then, insert the arm portion into the arm insertion through-hole of the rotating shaft 12 to a position where the length from the grip of the manual handle type drive unit 20 to the rotating shaft 12 is appropriate for the load of the cargo being towed. Next, insert the locking pin into the locking pin insertion through-hole and drop it into the locking hole in the arm portion, thereby removably fixing the manual handle type drive unit 20 to the rotating shaft 12.

However, in the present invention, the method of engaging the rotating shaft with the arm of the drive unit is not limited to this. For example, the head of the rotating shaft could be shaped like a hexagonal pillar, similar to the shape of a nut head, and the tip of the arm of the manual handle could be provided with a structure similar to a socket wrench that fits into the hexagonal pillar of the head of the rotating shaft, and the socket part could be fitted into the hexagonal pillar of the head of the rotating shaft, allowing the manual handle drive unit to be detachably fixed to the rotating shaft.

In addition, in this embodiment, the winch device 10 is driven by applying torque as input rotation to the rotating shaft 12 through manual operation of the manual handle type drive unit 20, but the present invention is not limited to this. For example, the winch device 10 may be driven using a power generating device or tool that can apply torque to the rotating shaft 12, such as an electric motor equipped with an appropriate rotation control device or an electric wrench. In other words, while the manual handle type drive unit 20 in this embodiment is manual, the drive unit of the present invention may be either manual or electric.

(rotation axis)
In this embodiment, the rotating shaft 12, which is a component of the winch 11, is a cylindrical member. However, in the present invention, the shape of the rotating shaft is not limited to this, and it may be, for example, a cylindrical, prismatic, crankshaft-like, or any other shape as long as it can transmit driving force to the components connected to both ends. A manual handle-type drive unit 20 is attached to the outer end (the right end in Figure 3) of the rotating shaft 12, which an operator can grip to operate the rotational movement.

When rotational power is directly applied to the rotating shaft 12 by the manual handle drive unit 20, rotational torque is transmitted to the input portion of the reducer 18 connected to the inside of the rotating shaft 12 (left side in Figure 3). In this manner, in the winch 11 of this embodiment, the manual handle drive unit 20, rotating shaft 12, reducer 18, transmission shaft 26, and spool 28 are connected in this order, and rotational force is transmitted sequentially from the manual handle drive unit 20 to each component. The spool 28 of the winch 11 winds up the towing member 22, towing and moving the cargo 32 placed on the loading platform upper surface 42A of the transportation device 40 connected to the towing member 22.

(housing)
The housing 14 according to this embodiment rotatably supports the rotating shaft 12 by means of bearings 24 provided on the wall surface of the through-hole. A reducer 18 is installed in the internal space of the housing 14, and the gear shaft of the input gear of the reducer 18 is connected to the rotating shaft 12 that penetrates the wall surface of the housing 14. In this embodiment, the housing 14 is a rectangular parallelepiped enclosure.

In this embodiment, the exterior shape of the housing 14 is a substantially sealed enclosure surrounded by plate-like members on all sides, but the present invention is not limited to this. As long as it can properly fix or support the reducer, rotating shaft, etc., prevents workers from coming into contact with moving parts such as the reducer gear or rotating shaft, and prevents external foreign objects from getting caught in the gear and damaging it, it may, for example, not have a plate-like member surrounding the entire periphery but may be shelf-like, made up of a single plate or multiple plate-like members.

In addition, while the housing 14 is made of resin in this embodiment, the present invention does not limit the housing material to this, and any material, such as metal or wood, may be used as long as it has the required robustness. Furthermore, when the housing is made of resin, it is lighter than when made of metal, making it easier to attach and detach from a forklift.

(reducer)
The reducer 18 according to this embodiment is configured by combining an input gear that is a spur gear with a small number of teeth and an output gear that is a spur gear with a large number of teeth, and when housed and installed inside the housing 14, is disposed adjacent to the manual handle type drive unit 20 on the outer surface (i.e., the outer side) of one end (lower side in FIG. 2) in the width direction (vertical direction in FIG. 2) of the backrest 94. Rotational power generated by the manual handle type drive unit 20, which is attached to the outer surface of the housing 14, is input to the input gear of the reducer 18 via the rotating shaft 12.

However, in the present invention, the configuration of the reducer is not limited to this, and for example, a paradox planetary gear mechanism using an internal gear can be used. By using a paradox planetary gear mechanism, a relatively large output rotational torque can be obtained even with a relatively small input rotational torque from human power via the manual handle drive unit 20. In addition, because the input and output shafts of the reducer are aligned, the reducer can be made smaller, which helps to make the winch device more compact and lightweight.

Note that although a speed reducer 18 is used in this embodiment, a speed reducer is not required in the present invention when the towed load is relatively light or when the rotational torque applied to the rotating shaft by the drive unit is sufficiently large.

In addition, while in this embodiment the rotating shaft 12 and the input shaft of the reducer 18 are arranged in a straight line, the present invention is not limited to this. For example, by connecting the rotating shaft to the input shaft of the reducer via a bevel gear, the rotating shaft can be attached at an appropriate angle, such as a 45-degree angle, to the input shaft of the reducer. This increases the degree of freedom in the attachment angle of the drive unit relative to the reducer, i.e., the options for the standing position of the operator operating the handle of the drive unit.

(Transmission shaft and bearing)
The transmission shaft 26 according to this embodiment is connected to the output shaft of the reducer 18. As shown in Fig. 3, the transmission shaft 26 extends along the width direction (left-right direction in Fig. 3) of the backrest 94. The transmission shaft 26 is rotatably supported by a bearing 24 provided on the front surface of an upper horizontal beam 94A of the backrest 94.

One end of the transmission shaft 26 is connected to the gear shaft of the output gear (not shown) of the reducer 18, and the other end is connected to the rotating shaft of the spool. While the present embodiment illustrates an example in which the number of bearings 24 is three, the present invention is not limited to this. The number of bearings can be any number greater than or equal to one, as long as it can suppress lateral vibration of the shaft accompanying rotation of the transmission shaft within an acceptable range and suppress deflection of the shaft due to reaction force from the towing member within an acceptable range. The transmission shaft 26 transmits rotational power generated by the manual handle-type drive unit 20 to the spool 28.

(spool)
3 , in this embodiment, two spools 28 are attached to the transmission shaft 26 at a distance from each other and are connected to the gear shaft of the output gear (not shown) of the reducer 18 via the transmission shaft 26, thereby receiving rotational force. The spools 28 are attached to the backrest 94 via the transmission shaft 26. The spools 28 are fixed to the transmission shaft 26 and reel in the towing member 22 in conjunction with the rotation of the transmission shaft 26. The spools 28 tow the load connected to the towing member 22.

However, in the present invention, the method of engaging the spool and transmission shaft is not limited to this. For example, a ratchet mechanism (not shown) may be interposed between the spool and transmission shaft, so that when the towing member wound on the spool is pulled from the spool to engage with the pallet, the spool is pulled by the towing member and rotates, but this rotation is not transmitted to the transmission shaft, and therefore the handle of the drive unit does not rotate with it.

In addition, while in this embodiment, two spools 28 are attached to the transmission shaft 26, the present invention is not limited to this and any number greater than one may be used depending on the application. If the number of spools attached to the transmission shaft is increased and the number of towing members is increased accordingly, the reaction force of the towing force acting on the transmission shaft when towing cargo is distributed to the positions of each spool, mitigating the concentration of localized force on the transmission shaft. This reduces the strength required of the transmission shaft and also reduces the number of bearings on the transmission shaft.

(Traction member)
In this embodiment, the pulling member 22 is fixed by being attached at one end (the right end in FIG. 2) to a substantially cylindrical hoisting drum (not shown) of the spool 28, and is connected to the load 32 by engaging an engaging portion (not shown) provided at the other end (the left end in FIG. 2) with an engaged portion (not shown) on the load 32. As the pulling member 22 in this embodiment, a belt is used, as shown in FIG. 2 in a state where it is wound around the spool 28.

However, the present invention is not limited to this, and any pulling member of any shape or material may be used, such as a wire, rope, steel cable, or chain, as long as it is long, thin, and flexible enough to be wound around a spool and has the required tensile strength. In this embodiment, the number of pulling members is two, but the present invention is not limited to this, and the number of pulling members can be one or more, depending on the number of spools attached to the transmission shaft.

(Another example of a method for engaging the spool with the traction member)
In this embodiment, the spool 28 and the pulling member 22 can be engaged in a manner different from the above-described method. That is, as shown in Fig. 4, one end of the pulling member 22 is fixed to the reel 28A of the spool 28 by shaving a portion of the periphery of the cylindrical reel 28A along the axial direction to make it flat, and then providing three screw holes in the flat portion 28A1, and folding back one end of the belt of the pulling member 22 to form a double portion 22A. The unity of the double portion 22A is enhanced by sewing the double portion 22A together at the seam 23 using a resin thread.

Then, screw holes are formed in the double portion 22A at positions (portions) facing the screw holes formed in the flat portion 28A1 of the winding drum 16A by pressing heated metal against it to melt it. The screw holes in the double portion 22A of the belt are then aligned with the screw holes in the flat portion 28A1, and the double portion 22A of the belt is then fastened to the flat portion 16A1 with screws 17 as fasteners, thereby fixing it in place.

Compared to fastening methods such as using adhesive to attach the belt ends to the round surface of the hoisting drum 16A, this method firmly secures the belt and prevents it from coming loose in the high summer temperatures that can cause the adhesive to melt. Even if a strong force is applied to the belt when towing a heavy load, there is little risk of the belt coming loose from the hoisting drum 16A.

Furthermore, in the other examples of this embodiment described above, even if the belt of the traction member 22 is wound around the hoisting drum 16A in multiple layers, a portion of the periphery of the hoisting drum 16A is thinned by the flat portion 16A1, so the thickness of the double portion 22A located in that portion prevents it from protruding from other portions, stabilizing the operation of the winch device 10 while the belt is wound around it. Note that the double portion of the belt, the seam portion, and the flat portion of the hoisting drum are not required in the present invention, and only some of these may be used.

As shown in Figure 4, the top of the screw 17 has a flat portion 17A with a surface perpendicular to the axial direction. The portion below the flat portion 17A of the top is hemispherical (dome-shaped), but this is not limited to this in the present invention, and it may also be shaped like a truncated cone, for example. Therefore, a corner 17B is formed at the boundary between the flat portion 17A of the head and the portion below it. When the belt is wound around the screw, the corner 17B bites into the belt, making it difficult for the wound belt to loosen. Note that the corner is not essential in the present invention.

In the present invention, the towing member may be connected to the pallet by, for example, directly tying the towing member to the leg of the pallet, or by using a towing aid such as a hook. Furthermore, depending on the number of spools provided, the towing member may be connected to one leg in the center of the pallet's width, or to both legs on the left and right sides of the width, or to any part of the wall or top surface of the pallet 30, and the connection position on the pallet is arbitrary. Furthermore, when cargo is placed on a sheet pallet, the towing member may be connected to the sheet pallet by, for example, a towing aid that clamps the edge of the sheet pallet.

(How to attach the bearing to the backrest)
In this embodiment, the bearing 24 is attached directly to the front surface of the upper horizontal bar 94A of the backrest 94, but in the present invention, the attachment position and attachment method of the bearing are not limited to this. For example, as shown in Figures 5 and 6, a mounting fixture 50 may be attached to the lower rail 96B, and the bearing 24 may be attached to the attachment surface of the support portion 52 of the attached mounting fixture 50.

Specifically, the mounting fixture 50 has a plate-shaped support portion 52, a first protrusion 54 extending downward from the end of the support portion 52, and a second protrusion 56 extending downward from near the center of the support portion 52, spaced apart from the first protrusion 54.

In the example shown in Figure 5, a plate-shaped connecting plate 58 is provided at one end (right side in Figure 5) of the support part 52 of the mounting fixture 50 in the width direction (left and right direction in Figure 5). Although not shown, the connecting plate 58 can be fixed to the support part 52 by screwing, for example, at the lower end of the connecting plate 58 in Figure 5, while in contact with the right end face of the support part 52. The reducer 18 and manual handle-type drive unit 20 are attached to the right side of the connecting plate 58 in Figure 5 by bolting, welding, etc.

The mounting fixture 50 shown in Figure 5 functions in the same way as the components that make up the backrest 94. That is, the mounting surface of the support portion 52 of the mounting fixture 50 corresponds to the front side of the upper cross beam 94A, upper rail 86A, or lower rail 96B of the backrest 94. In addition, the manual handle drive unit 20 attached to the right side of the connecting plate 58 fixed to the support portion 52 of the mounting fixture 50 in Figure 5 corresponds to the drive unit located on the outer surface of the backrest 94. The upper cross beam 94A, upper rail 96A, and lower rail 96B correspond to the mounted members in this invention.

In addition, in Figure 5, the bearing 24 can be attached to the upper surface of the plate-shaped support portion 52 of the mounting fixture 50 by bolting, welding, etc. Although not shown, a plate-shaped mounting portion extending vertically along the up-down direction may be provided on the right end surface of the support portion 52 in Figure 6, and the bearing 24 may be attached to the front surface of the mounting portion by bolting, welding, etc.

Also, in Figure 5, a gap through which the vertical portion of the fork 98 passes is formed on the side of the support part 52 of the mounting fixture 50 closer to the vertical portion of the fork 98 (left side in Figure 6). That is, the bearing 24 is supported on the upper surface of the support part 52 at a position further toward the tip (right side in Figure 6) than the vertical portion of the fork 98 by the amount of the gap. Therefore, even if the vertical portion of the fork 98 moves left and right along the upper rail 96A, it does not interfere with the support part 52. In other words, while the bearing 24 is supported on the upper surface of the support part 52 closer to the tip of the vertical portion of the fork 98, the vertical portion of the fork 98 can slide widthwise inside the gap.

As shown in Figure 6, the second protrusion 56 of the mounting fixture 50 has a bolt hole 56A that penetrates perpendicularly to the plate surface. A female thread is formed in the bolt hole 56A, and the male thread of the shank of the pressure bolt 60 is inserted into the bolt hole 56A for screw connection.

As shown in Figure 6, when the pressure bolt 60 is screwed into the bolt hole 56A, the tip side (left side in Figure 6) opposite the head of the pressure bolt 60 presses against the front surface of the upper part of the lower rail 96B, pressing it against the first protrusion 54, thereby fixing the mounting fixture 50 to the lower rail 96B. Note that in the present invention, the mounting position of the mounting fixture is not limited to this, and it may be fixed to, for example, the upper horizontal rail 94A of the backrest or the upper rail.

The configuration of the mounting fixture 50 in Figure 6 is merely one example. In the present invention, for example, a mounting arm may branch off from a single fastening portion to provide multiple mounting surfaces. Conversely, if mounting strength is required, multiple fastening portions may be provided for a single mounting surface. Furthermore, either one component or multiple components may be attached to a single mounting surface.

In the present invention, the mounting height of the bearing may be the height of the upper cross rail 94A of the backrest 94, which is above the upper rail 96A, as in bearing 24 in Figure 3, or the height of the upper rail 96A, or the height of the lower rail 96B. In other words, the mounting height of the bearing can be adjusted as needed. Furthermore, the support part of the mounting fixture can be shaped so that the height of the mounting surface is changed by bending the middle part upward or downward and then bending it horizontally again, or the middle part can be twisted so that the mounting surface faces to the side.

Here, in an example that does not use a mounting fixture, such as the winch device 10 according to this embodiment in Figure 1, the placement position of the winch 11 in the width direction and the attachment position of the winch 11 to the backrest 94 coincide in that they are on the same end side. However, as in the example in Figure 5 that uses a mounting fixture, in the present invention, the placement position of the winch 11 in the width direction and the attachment position of the winch 11 to the backrest 94 do not necessarily have to coincide.

In this way, the towing height of the winch device of the present invention can be changed depending on, for example, the dimensions of the load to be towed or the height at which the load is placed. Furthermore, by providing an appropriately shaped mounting fixture, all of the components that make up the winch of the present invention can be detachably attached to the forklift using the mounting fixture, without having to drill screw holes or other holes in the forklift's original components.

In the installation method illustrated in Figures 5 and 6, the manual handle drive unit 20, reducer 18, and spool 28 are all attached to the backrest 94 via the mounting fixture 50, which can be attached to the workpiece by clamping the lower rail 96B of the workpiece using the tightening force of the pressure bolt 60. Therefore, when installing or removing the winch device 10 of this embodiment, there is no need to modify the original components of the forklift 90.

As a result, even those who are not experts in forklift manufacturing and repair (for example, even forklift users) can easily attach and detach the winch device of this embodiment. Furthermore, when the winch function is no longer needed, the winch device can be removed and the forklift can be returned to its original, basic configuration without the winch device, allowing it to be used again. This is advantageous in that it reduces the burden of having to modify the basic configuration of the forklift in advance, for example, when installing a winch device on a forklift.

(Unloading method)
Next, a method for unloading cargo using the winch device 10 according to this embodiment will be described with reference to FIGS.

In this embodiment, a case is described in which pallets 30 carrying cargo 32 are stacked in two rows along the width direction on the loading platform 42 of the transportation device 40, but the present invention is not limited to this. The cargo may be stacked in a single row, or in three or more rows depending on the style of packaging.

Furthermore, in the present invention, it is not necessary for the cargo to be placed on a wooden or plastic platform-type pallet device; it may be placed on another pallet device, such as a sheet pallet. Alternatively, if the cargo is in a form that allows it to be connected to a towing member, it may be placed directly on the floor of the transportation device without being placed on a pallet device, and the towing member may be connected and the cargo unloaded.

As shown in Figure 7, first, the operator 80 of the forklift 90 positions the forklift 90, with the winch device 10 attached, at any position in the width direction of the rear end of the transport device 40. Next, the operator 80 adjusts the position of the forklift 90 so that the row of pallets 30 and the forklift 90 overlap in a straight line in the towing direction. Then, the operator 80 moves the backrest 94 of the forklift 90 up and down to align the height of the spool 28 with the height of the pallets 30.

Next, the operator 80 gets off the forklift 90 and pulls the tip of the towing member 22 of the winch device 10, unwinding it from the spool 28. Once it reaches the front part of the foremost pallet 30 on the loading platform 42, the operator engages the tip of the towing member 22 with the support post on the front side of the pallet 30. Note that in the present invention, a worker other than the operator 80 may operate the winch device 10 without the operator 80 getting off the forklift 90. In other words, the operator 80 of the forklift 90 and the worker performing the unloading work may work together.

Next, as shown in FIG. 8 , the operator 80 activates the manual handle drive unit 20 of the winch device 10 to pull the pallet 30 and pull it out to a position on the loading platform 42 where the forks of the forklift 90 can be inserted. Next, the operator 80 disengages the towing member 22 from the pallet 30 and removes the towing member 22 from the pallet 30. The operator 80 then rewinds the towing member 22 and stores the tip end on the spool 28.

Next, as shown in Figure 9, the operator 80 gets on the forklift 90 and raises or lowers the backrest 94 to adjust the height of the forks 98 so that they can be inserted into the pallet 30. The operator 80 then uses the forklift 90 to remove the extracted pallet 30 from the loading platform 42 of the transportation device 40 and transport it to the specified location.

The above series of steps explained using Figures 7 to 9 are repeated to sequentially unload the pallets 30 loaded on the loading platform 42. Note that in the present invention, the order of the unloading rows can be arbitrary; unloading of one row may be completed before unloading of another row, or unloading may be performed randomly from multiple rows. In this manner, the unloading method according to this embodiment can be configured. According to the unloading method according to this embodiment, cargo can be easily removed from the loading platform 42 of the transportation device 40.

Furthermore, with the unloading method according to this embodiment, the operator 80 of the forklift 90 can unload the cargo by himself. In other words, the labor required for the unloading work can be reduced. Therefore, even if it is difficult to secure a worker in addition to the operator 80, or even if the number of workers required for the unloading work is limited, the unloading work can be carried out smoothly.

(Action and effect)
In this embodiment, the manual handle type drive unit 20, which is one of the components of the winch 11, is attached to a backrest 94 that is originally provided on the forklift 90, and is positioned outside one end in the width direction of the backrest 94. In this way, the components of the winch 11 can be attached to the forklift 90 without the need to add additional members in addition to the fork 98 and backrest 94 that are originally provided on the forklift 90, such as the sheath fork and backrest for the sheath fork shown in Japanese Patent Application Laid-Open No. 2002-167191.

As a result, a winch device 10 can be provided that has a simple structure and can easily pull out cargo 32 from the loading platform 42. In other words, due to its simple structure, it is easy to attach to a forklift 90, can efficiently pull out multiple cargoes 32 from the loading platform 42, and can be easily operated by the operator 80 (worker) using a manual handle.

Furthermore, when a manual handle drive unit 20 is used as the means for generating rotational power in the winch 11, as in this embodiment, the configuration of the manual handle that can be connected to other components of the winch 11 and the location of the manual handle on the forklift 90 must be considered with safety in mind. In this regard, prior art, such as Japanese Patent Application Laid-Open No. 2002-167191, discloses a winch in which all components are integrated and placed inside a pair of forks, but does not disclose the configuration of the manual handle that can be connected to separate components of the winch or the location of the manual handle on the forklift.

However, in this embodiment, the manual handle drive unit 20 is positioned outside one widthwise end of the backrest 94 of the forklift 90 and on the outside of the forks 98. This allows the operator to rotate the manual handle from a position on the outside of the forks 98, thereby improving the safety and operability of the winch device 10 compared to, for example, when the operator is positioned inside the forks 98 or reaches inside the forks 98 to rotate the manual handle.

In addition, in this embodiment, the housing 14 that houses the relatively bulky reducer 18, a component of the winch 11, is also provided on the outer surface of the widthwise end of the backrest 94, similar to the manual handle drive unit 20. This makes it less likely that the components of the winch 11 will interfere with the pallet inserted into the forks 98 or the cargo 32 on the pallet.

<Other embodiments>
Although the present invention has been described by the embodiments disclosed above, the descriptions and drawings forming part of this disclosure should not be understood as limiting the present invention. It should be considered that various alternative embodiments, examples, and operating techniques will become apparent to those skilled in the art from the present invention.

(Modification)
Next, a winch device 10A according to a modified example will be described with reference to Figures 10 to 12. The winch 11 according to the modified example includes a manual handle type drive unit 20, a rotating shaft 12, a connecting shaft 27, a housing 14, a reducer 18, and a spool 28, similar to the present embodiment.

However, in this modified example, the reducer 18 is positioned in the center of the width of the backrest 94, rather than at the end of the width of the backrest 94 as in this embodiment; the reducer 18 and spool 28 are therefore closer together, eliminating the need for the transmission shaft 26. Instead, a connecting shaft 27 is added to connect the rotating shaft 12 and the reducer 18; and the spool 28 is housed in the housing 14 together with the reducer 18. Below, we will mainly explain the configuration that differs from this embodiment, and will omit redundant explanations of the configuration that is similar to this embodiment.

As shown in Figure 10, the speed reducer 18 in this modified example is located at the center of the width direction (vertical direction in Figure 10) of the backrest 94, separate from and not adjacent to the manual handle type drive unit 20, and the rotational force generated by the manual handle type drive unit 20 is input via the rotation shaft 12 and the connecting shaft 27.

The rotary shaft 12 is directly supplied with rotational power generated by the manual handle drive unit 20 by the manual handle drive unit 20. The connecting shaft 27 connects the rotary shaft 12 to which the rotational power has been applied and the input shaft of the reducer 18 inside the housing 14, thereby transmitting the rotational power.

Specifically, as shown in Figures 11 and 12, the housing 14 according to the modified example is placed on the upper surface of the support portion 52 at the top of the mounting fixture 50. Note that in Figure 11, components other than the winch device 10A, backrest 94, and fork 98 have been omitted from the illustration for clarity. As shown in Figure 12, the mounting fixture 50 according to the modified example has a plate-shaped support portion 52, a first protrusion 54 extending downward in Figure 12 from the end of the support portion 52, and a second protrusion 56 extending downward from near the center of the support portion 52, spaced apart from the first protrusion 54.

As shown in FIG. 12, the second protrusion 56 of the mounting fixture 50 has a bolt hole 56A that penetrates perpendicularly to the plate surface. A female thread is formed in the bolt hole 56A, and the male thread of the shank of the pressure bolt 60 is inserted and screwed into it. As shown in FIG. 12, when the pressure bolt 60 is screwed into the bolt hole 56A, the tip side opposite the head of the pressure bolt 60 (left side in FIG. 12) presses against the front surface of the upper part of the upper rail 96A, pressing it against the first protrusion 54, thereby fixing the mounting fixture 50 to the upper rail 96A. Note that the mounting position of the mounting fixture is not limited to this, and it may be fixed to, for example, the upper cross rail 94A or lower rail 96B of the backrest.

The reduction gear 18 and spool 28 are installed in the internal space of the housing 14 according to this modified example. The spool 28 is installed inside the housing 14 so that it can rotate freely. The spool 28 is attached adjacent to the reduction gear 18 on the left side of the reduction gear 18 in Figure 11. The spool 28 is directly connected to the output shaft of the reduction gear 18.

The rotating shaft of the spool 28 is directly connected to the gear shaft of an output gear (not shown) that protrudes toward the spool 28 from the reducer 18, which is located to the right of the spool 28 in Figure 11. Rotational force is applied to the spool 28 from the manual handle-type drive unit 20 via the rotating shaft 12, connecting shaft 27, and reducer 18.

Figure 11 shows an example in which a spool 28 with a traction member 22 attached is positioned at the position of the opening 14A formed in the front of the housing 14. The spool 28 can wind up the traction member 22 and also unwind it to pull out the traction member 22 from the opening 14A. Note that in the present invention, the position of the housing 14 and the position of the spool 28 in the width direction can be changed as appropriate.

The towing member 22 according to the modified example has one end (the right end in FIG. 10) attached and fixed to the substantially cylindrical hoisting drum (not shown) of the spool 28, and is connected to the cargo 32 by engaging an engaging portion (not shown) provided on the other end (the left end in FIG. 10) with an engaged portion (not shown) on the cargo 32. The rest of the structure of the winch device 10A according to the modified example is the same as the structure of the winch device 10 according to the present embodiment described using FIGS. 1 to 10, so repeated explanations will be omitted.

(Effects of Modified Example)
As with the present embodiment, the winch device 10A according to the modified example also has a simple structure and can easily pull out the load 32 from the loading platform 42. Furthermore, in the modified example, the reducer 18 is attached to the center of the backrest 94 in the width direction. This makes it easier to stabilize the center of gravity of the entire forklift 90 compared to, for example, when the reducer 18 is attached to an end of the backrest 94 in the width direction. Other effects of the modified example are the same as those of the present embodiment.

In addition, the present invention can also be constructed by partially combining the configurations illustrated in the attached drawings. As stated above, the present invention includes various embodiments not described above, and the technical scope of the present invention is defined only by the invention-specifying matters in the claims that are appropriate from the above description.

10, 10A Winch device 11 Winch 12 Rotating shaft 14 Housing 14A Opening 17 Screw 17A Flat portion 17B Corner portion 18 Reducer 20 Manual handle type drive unit (drive unit)
22 Traction member 22A Double portion 23 Seam portion 24 Bearing 26 Transmission shaft 27 Connecting shaft 28 Spool 28A Winding drum portion 28A1 Flat portion 30 Pallet 32 Luggage 40 Transportation device 42 Cargo bed 42A Cargo bed upper surface 50 Mounting fixture 52 Support portion 54 First protrusion 56 Second protrusion 56A Bolt hole 58 Connecting plate 60 Presser bolt (bolt)
80 Operator 90 Forklift 92 Mast 94 Backrest 94A Upper cross bar 96A Upper rail (mounting member)
96B Lower rail (mounting member)
98 Fork 98A Fork riser

Claims (2)

a bearing attached to a backrest that moves up and down along the mast of the forklift together with the forks;
a shaft whose both ends are supported by the bearings;
a spool provided on the shaft and around which a towing member is wound to tow the connected load toward the fork ;
a reducer connected to one end of the shaft and provided on the outer side of the backrest in the width direction ;
a handle connected to the outside of the reducer for manually rotating the shaft via the reducer ;
A winch device comprising: The bearing is attached to the backrest via a mounting fixture that can be attached to a mounting member by clamping the mounting member using the fastening force of a bolt.
The winch device according to claim 1 .