FI130966B1

FI130966B1 - Lifting device and machine

Info

Publication number: FI130966B1
Application number: FI20235687A
Authority: FI
Inventors: Kari Toivonen
Original assignee: Kupari Kari Oy
Priority date: 2023-06-19
Filing date: 2023-06-19
Publication date: 2024-06-20
Also published as: FI20235687A1

Abstract

The invention relates to a lifting device for facilitating the operator of a machine (1) to access the cabin (10) of the machine (1), wherein the lifting device (30) comprises a first ladder arrangement (31) and a second ladder arrangement (32); the lifting device (30) comprises an actuator arrangement (33) connected to the first ladder arrangement (31) and to the second ladder arrangement (32); the actuator arrangement (33) is arranged to move the first ladder arrangement (31) in a first vertical direction (D1) and the second ladder arrangement (32) in a second vertical direction (D2) as a response to a force (F) applied by the operator on at least one foothold (311) of the first ladder arrangement (31). The invention relates also to a machine comprising a cabin (10), a machine body (20), and a lifting device (30) as defined above connected to the machine body (20).

Description

LIFTING DEVICE AND MACHINE

FIELD OF THE INVENTION

The present invention relates to lifting devices, and more precisely to a lifting device for facilitating an operator of a machine to access the cabin of the machine.

BACKGROUND OF THE INVENTION

The cabin for an operator in machines, such as heavy vehicles like trucks, is usually so high that the operator, such as the driver, needs to climb to reach the cabin. Therefore the operator needs to be in a good physical shape to be able to perform the climb. Climbing to the cabin repeatedly during the working shift causes physical stress even to an operator being in a good physical shape and increases the risk of getting musculoskeletal diseases and tires the operator. It is commonly known that when tired, people make more mistakes which in turn cause more accidents. It is also time-consuming to climb up to the cabin of the machine several times during the shift, especially if the cabin is located high up from the ground.

There have been some attempts to overcome problems as can be seen from the documents cited below.

Document KR20110053750A discloses an elevating scaffold for a freight car to improve convenience by enabling a passenger to vertically elevate the scaffold n 20 only when the passenger steps on the scaffold.

N

< Document EP0778177A2 discloses a working vehicle containing a chassis

O with a driver's cabin which is eguipped with a step construction with at least one step.

D The step is coupled to a lifting and lowering device which is controllable by means of

T switching devices which are located at least in the vicinity of the step construction. a

J 25 Document DE3618477A1 discloses a lift assigned laterally to the driver's 3 cab of a heavy lorry, by means of which the driver and/or passenger can enter the

O driver's cab from the roadway and/or can return to the roadway from the driver's cab without having to negotiate relatively high steps. The lift is a raisable and lowerable platform, on which the driver can modify his position in a vertical direction while standing. A stationary vertical gripping rod provides the person standing on the platform with support and helps to guide the lift plate. The drive is partly arranged inside the gripping rod.

Document US2016339845A1 discloses a driver lift device lifting a driver to enter an elevated cab on farm equipment or the like. The device includes an elongated post vertically mounted to a vehicle proximate an entry into a cab of the vehicle. Each of a top end and a bottom end of a pole is coupled to the post such that the pole is positioned in parallel spaced relationship to the post. Each of a plurality of rollers is coupled to a housing defining a vertical path through the housing. The pole extends through the vertical path. A foot support is coupled to the housing. A winch is coupled to the top end of the pole. A strap couples the housing to the winch whereby operation of the winch elevates and lowers the foot support on the pole.

A problem with all the above applications is that if the lifting device malfunctions, either the operator is not able to reach the cabin or to get down from the cabin at all. This is because there is only one platform or foothold taking care of lifting and optionally lowering the operator to and from the cabin.

BRIEF DESCRIPTION OF THE INVENTION

An object of the present invention is to provide a lifting device and a machine that overcome the above problems.

The objects of the invention are achieved by the lifting device and the

D machine which are characterized by what is stated in the independent claims. The

N preferred embodiments of the invention are disclosed in the dependent claims. 3 The invention is based on the idea of providing a lifting device for

T facilitating the operator of a machine to access the cabin of the machine, wherein the

E: 25 lifting device comprises a first ladder arrangement; the first ladder arrangement 5 comprises at least one foothold; the first ladder arrangement is arranged to be moved 3 in a vertical direction, the lifting device comprises a second ladder arrangement

O arranged adjacent and parallel to the first ladder arrangement, the second ladder arrangement comprising at least one foothold and being arranged to be moved in a vertical direction; the lifting device comprises an actuator arrangement connected to the first ladder arrangement and to the second ladder arrangement; the actuator arrangement is arranged to move the first ladder arrangement in a first vertical direction and the second ladder arrangement in a second vertical direction opposite the first vertical direction as a response to a force applied by the operator on the at least one foothold of the first ladder arrangement; and the actuator arrangement is arranged to move the second ladder arrangement in the first vertical direction and the first ladder arrangement in the second vertical direction as a response to a force applied by the operator on the at least one foothold of the second ladder arrangement.

In other words, the actuator arrangement is arranged to move each ladder arrangement automatically when the operator steps with one foot on the foothold of the corresponding ladder arrangement. The second ladder arrangement moves always in an opposite direction to the first ladder arrangement. When the movement of the ladder arrangement has reached its terminal position, the operator can step with another foot on a foothold of the adjacent ladder arrangement, which then continues the movement in the desired direction. The lifting device can be used for escalating to the cabin from the ground but also for lowering to the ground from the cabin. The movement of the ladder arrangements is similar to so called man engine or

Fahrkunst used in mines in 19th century with the exception that in the current invention, the movement is not continuous but only generated as a response to the force applied by the operator to the foothold of a ladder arrangement.

An advantage of the invention is that because there is a second ladder @ arrangement that moves in the opposite direction to the first ladder arrangement, the & operator is able to climb up or down the first and second ladder arrangements in case 8 there is a malfunction in the lifting device. In the worst case, the first ladder

D 25 arrangement is in a position in which all the footholds are parallel or close to parallel = with the footholds of the second ladder arrangement. Even in this case it is possible - to climb up or down the ladder arrangements provided that the distance between two & footholds is not too long for the operator.

N

&

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is described in detail by means of specific embodiments with reference to the enclosed drawings, in which

Figure 1 is schematic side view of a machine comprising a lifting device according to an embodiment of the invention;

Figure 2 is a schematic side view of a lifting device according to an embodiment of the invention;

Figure 3 is a schematic rear view of a lifting device according to an embodiment of the invention, wherein the second ladder arrangement is illustrated as translucent to facilitate understanding of the design; and

Figure 4 is a schematic side view of a lifting device according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The invention relates to a lifting device 30 for facilitating the operator of a machine 1 to access the cabin 10 of the machine 1. For example, the machine 1 is a vehicle, such as a van, a truck, a lorry, a tractor, a loader, an excavator, a locomotive, or a mobile crane; or a stationary machine, such as a fixed crane. The lifting device 30 is also suitable for facilitating raising to other elevated structures such as loading platforms. = 20 First and second ladder arrangement

O

N

A The lifting device 30 comprises a first ladder arrangement 31. The first

O o ladder arrangement 31 comprises at least one foothold 311. The first ladder = arrangement 31 is arranged to be moved in a vertical direction between a lower

E terminal position and an upper terminal position.

K

2 25 The lifting device 30 comprises a second ladder arrangement 32. The 0

SG second ladder arrangement 32 is arranged adjacent and parallel to the first ladder

O

N arrangement 31. The second ladder arrangement 32 comprises at least one foothold

321. The second ladder arrangement 32 is arranged to be moved in a vertical direction between a lower terminal position and an upper terminal position.

In this context, term vertical direction means a direction which is deviated at most 45°, preferably at most 30°, more preferably at most 20°, from an axis that is 5 transversal to a level surface, i.e. parallel with a plumb axis. In other words, the ladder arrangements 31, 32 may be in an inclined position. The inclination may be in any direction depending on the structure of the machine 1.

In other words, the first ladder arrangement 31 and the second ladder arrangement 32 are arranged parallel to each other. Preferably the lateral distance between the first ladder arrangement 31 and the second ladder arrangement is 2 to 20 cm.

According to some embodiments the first ladder arrangement 31 comprises at least two footholds 311 spaced apart in the vertical direction; and the second ladder arrangement 32 comprises at least two footholds 321 spaced apartin the vertical direction. More than one foothold 311, 321 allows covering a greater vertical distance than only one foothold 311, 321 while keeping the distance between the footholds 311, 321 such that they are still convenient for the operator to use as normal step ladders.

According to some embodiments, each two consecutive footholds 311 of the first ladder arrangement 31 are spaced 10 to 30 cm apart; and each two consecutive footholds 321 of the second ladder arrangement 32 are spaced 10 to 30 & cm apart. This is to keep the distance between the footholds 311, 321 such that they

N are still convenient for the operator to use as normal step ladders. Preferably, the = distance between the footholds 311 of the first ladder arrangement 31 is the same as = 25 the distance between the footholds 321 of the second ladder arrangement 32. : The number of footholds 311 in each ladder arrangement 31, 32 depends 2 on the vertical distance that is desired to be covered with the lifting device 30, usually 3 the vertical distance between the cabin 10 and the ground G.

N According to some embodiments, the distance between the lower terminal position and the upper terminal position is 10 to 30 cm. In this way, when the ladder arrangements 31, 32 comprise more than one foothold 311, 321 and when the operator steps on the first foothold 311 of the first ladder arrangement 31, the first ladder arrangement 31 moves in the desired direction, and the movement of the first ladder arrangement 31 is such that the operator can step on the second foothold 321 of the second ladder arrangement 32, which then continues the movement in the desired direction until the operator is able to reach the desired destination, i.e. the cabin or the ground.

Preferably, when the ladder arrangements 31, 32 comprise at least two footholds 311, 321, the distance between the lower terminal position and the upper terminal position and the distance between the footholds 311 and 321 are selected such that in the terminal position of the first ladder arrangement 31, the first foothold 311 of the first ladder arrangement 31 is aligned with the second foothold 321 of the second ladder arrangement 32, and in the terminal position of the second ladder arrangement 32, the first foothold 321 of the second ladder arrangement 32 is aligned with the second foothold 311 of the first ladder arrangement 31. In this context, aligned means that the distance between the footholds 311, 321 in a vertical projection is less than 2 cm. In this context, the first foothold means the uppermost or the lowest foothold, and the second foothold means second to uppermost or second to lowest, correspondingly.

Actuator

The lifting device 30 comprises an actuator arrangement 33. The actuator & arrangement 33 is connected to the first ladder arrangement 31 and to the second

N ladder arrangement 32. According to some embodiments, the actuator arrangement = 33 comprises an electric motor, a hydraulic actuator, or a pneumatic actuator.

I 25 The actuator arrangement 33 is arranged to move the first ladder a

N arrangement 31 in a first vertical direction D1 and the second ladder arrangement 32 2 in a second vertical direction D2 opposite the first vertical direction D1 as a response

S to a force F applied by the operator on the at least one foothold 311 of the first ladder

N arrangement 31.

The actuator arrangement 33 is further arranged to move the second ladder arrangement 32 in the first vertical direction D1 and the first ladder arrangement 31 in the second vertical direction D2 as a response to a force F applied by the operator on the atleast one foothold 321 of the second ladder arrangement 32.

According to some embodiments, the actuator arrangement 33 comprises a single actuator arranged to move both the first ladder arrangement 31 and the second ladder arrangement 32. In this embodiment, the first ladder arrangement 31 and the second ladder arrangement 32 are connected to a single power transmission arrangement arranged to transmit power between the actuator 33 and the firstladder arrangement 31 and between the actuator 33 and the second ladder arrangement 32.

In this way, synchronized movement of the ladder arrangements 31, 32 can be ensured.

According to some other embodiments, the actuator arrangement 33 comprises a dedicated actuator for each ladder arrangement 31, 32. In this embodiment, actuators dedicated for each ladder arrangement 31, 32 are preferably connected to each other to allow synchronized operation of the actuators.

According to some embodiments, the actuator arrangement 33 comprises more than one actuator dedicated for each ladder arrangement 31, 32, wherein all actuators are arranged to move in synchronization. This may be necessary if the ladder arrangements 31, 32 comprise many footholds, i.e. the ladder arrangements 31, 32 are heavy.

O

N According to some embodiments, the first vertical direction D1 is a

N direction away from the ground G and the second vertical direction D2 is a direction = towards the ground G. This embodiment is used, when the operator desires to reach = 25 the cabin 10, i.e. the lifting device 30 lifts the operator upwards. a - According to some embodiments, the first vertical direction D1 is a & direction towards the ground G and the second vertical direction D2 is a direction

N away from the ground G. This embodiment is used, when the operator desires to exit

N the cabin 10, i.e. the lifting device 30 lowers the operator downwards.

Power transmission

According to some embodiments, the lifting device 30 comprises a first pulley 34a, a second pulley 35a, and a belt 36a wrapped around the first pulley 34a and the second pulley 35a. The actuator arrangement 33 is connected to the first pulley 34a. The first ladder arrangement 31 and the second ladder arrangement 32 are connected to the belt 36a. In other words, the power transmission is implemented with a belt drive. In this embodiment, the torque transmitted from the actuator arrangement 33 to the first pulley 34a can be adjusted by adjusting the tightness of the belt 36a around the first pulley 34a and the second pulley 35a.

According to some alternative embodiments, the lifting device 30 comprises a first sprocket 34b, a second sprocket 35b, and a chain 36b meshing with the first sprocket 34b and the second sprocket 35b. The actuator arrangement 33 is connected to the first sprocket 34b. The first ladder arrangement 31 and the second ladder arrangement 32 are connected to the chain 36b. In other words, the power transmission is implemented with a belt drive.

According to some alternative embodiment, the actuator arrangement 33 comprises a first linear actuator 331 and a second linear actuator 332. For example, the linear actuators 331, 332 are hydraulic actuators or pneumatic actuators. The first linear actuator 331 is connected to the first ladder arrangement 31 and the second linear actuator 332 is connected to the second ladder arrangement 32. According to further embodiments, the firstlinear actuator 331 and the second linear actuator 332

O are connected, for example hydraulically or pneumatically, to each other to allow a synchronized movement of the linear actuators 331, 332 in opposite directions. 2

D Force detector

E 25 According to some embodiments, the lifting device 30 comprises a first

N force detector 37, a second force detector 38, and a control device 39. The first force & detector 37 is connected to the first ladder arrangement 31. The second force detector

N 38 is connected to the second ladder arrangement 32. The control device 39 is

N connected to the first force detector 37, to the second force detector 38, and to the actuator arrangement 33. The first force detector 37 is arranged to detect the force applied by the operator on the at least one foothold 311 of the first ladder arrangement 31. The second force detector 38 is arranged to detect the force applied by the operator on the atleast one foothold 321 of the second ladder arrangement 32.

The control device 39 is arranged to control the operation of the actuator arrangement 33 based on the force detected by the first force detector 37 or the second force detector 38. In this way, the operation of the lifting device 30 can be controlled more precisely and the structure of the lifting device 30 can be made simpler. Instead of controlling the operation of the actuator arrangement 33 with the force detectors 37, 38 and the control device 39, the lifting device can comprise a mechanical means (not shown in the figures) for sensing the force F applied on the foothold 311, 321 and operating the actuator arrangement 33.

Disabling operation

According to some embodiments, the lifting device 30 comprises disabling means 41 connected to the actuator arrangement 33 for disabling the operation of the lifting device 30 by the operator. In this way, the lifting device 30 can be used only for entering the cabin 10, for example. When the operator desires to exit the cabin 10, they can disable the operation of the lifting device 30 and climb down the first ladder arrangement 31 and the second ladder arrangement 32 just as they were normal step ladders. When the operator desires to enter the cabin 10, they can then enable the operation of the lifting device 30. The disabling means 41 can also be used to disable the operation of the lifting device 30 due to a situation too dangerous to use the lifting & device, for example. For example, the disabling means comprises a power switch.

N According to some embodiments, the cabin 10 comprises a door 11 having = a closed position and an open position. The machine 1 comprises a door position = 25 sensing means (not shown in the figures) connected to the lifting device 30 for sensing a a the position of the door 11. The lifting device 30 is arranged to disable the operation 2 of the actuator arrangement 33 when the door 11 is in the closed position. In this way, 2 the lifting device cannot be used unless the door is open. This will prevent accidental

R operation of the lifting device 30 for example due to an external object applying force on the foothold 311, 321 during the operation of the machine 1.

Selection of direction

According to some embodiments, the actuator arrangement 33 is arranged to move the firstladder arrangement 31 from the lower terminal position to the upper terminal position as a response to the application of force F on the at least one foothold 311 of the first ladder arrangement 31 when the first ladder arrangement 31 is in the lower terminal position. In these embodiments, the actuator arrangement 33 is also arranged to move the first ladder arrangement 31 from the upper terminal position to the lower terminal position as a response to the application of force F on the at least one foothold 311 of the first ladder arrangement 31 when the first ladder arrangement 31 is in the upper terminal position. In these embodiments, the actuator arrangement 33 is also arranged to move the second ladder arrangement 32 from the lower terminal position to the upper terminal position as a response to the application of force F on the at least one foothold 321 of the second ladder arrangement 32 when the second ladder arrangement 32 is in the lower terminal position. In these embodiments, the actuator arrangement 33 is also arranged to move the second ladder arrangement 32 from the upper terminal position to the lower terminal position as a response to the application of force F on the atleast one foothold 321 of the second ladder arrangement 32 when the second ladder arrangement 32 is in the upper terminal position. In other words, the operation direction of the lifting device depends on the position of the ladder arrangements 31, 32 as well as the foothold 311, 321 on which the operator applies the force F, and the operation direction is

JN selected automatically based on the foothold 311, 321 on which the operator applies

S the force F. 8 Preferably, in the previous embodiment, the actuator arrangement 33 is

D 25 arranged to disregard the continued application of force F after the ladder = arrangement 31, 32 has reached the terminal position until the user removes the force - F and applies it again. In other words, the actuator arrangement 30 is arranged to stop & operation when the ladder arrangement 31, 32 reaches the terminal position and until & the force F is applied again either on the foothold 311, 321 of the same ladder

N 30 arrangement 31, 32, or on the foothold 311, 321 of the other ladder arrangement 31, 32. This is to prevent the operation direction of the lifting device 30 from being reversed immediately when the ladder arrangement 31, 32 reaches the terminal position.

According to some other embodiments, the lifting device 30 comprises selecting means 40 connected to the actuator arrangement 33 for selecting the first vertical direction D1 between a direction away from the ground G and a direction towards the ground G. In this way, thelifting device can be switched between upwards and downwards movement so that it can be used for both entering the cabin 10 and exiting the cabin 10. For example, the selecting means 40 comprises a switch.

Machine

The invention relates also to a machine. The machine comprises a cabin 10, a machine body 20, and a lifting device 30 as defined above connected to the machine body 20.

According to some embodiments, the machine 1 is a vehicle, such as a van, a truck, a lorry, a tractor, a loader, an excavator, or a locomotive; or a stationary machine, such as a crane.

The invention has been described above with reference to the examples shown in the figures. However, the invention is in no way restricted to the above examples but may vary within the scope of the claims.

O

N

O

N

O

I o

I

[an a

K

00 ©

LO

O

N

O

N

Claims

1. Alifting device for facilitating the operator of a machine (1) to access the cabin (10) of the machine (1), wherein the lifting device (30) comprises a first ladder arrangement (31); the first ladder arrangement (31) comprises at least one foothold (311); and the first ladder arrangement (31) is arranged to be moved in a vertical direction between a lower terminal position and an upper terminal position, characterized inthat the lifting device (30) comprises a second ladder arrangement (32) arranged adjacent and parallel to the firstladder arrangement (31), the second ladder arrangement (32) comprising at least one foothold (321) and being arranged to be moved in a vertical direction between a lower terminal position and an upper terminal position; the lifting device (30) comprises an actuator arrangement (33) connected to the first ladder arrangement (31) and to the second ladder arrangement (32); the actuator arrangement (33) is arranged to move the first ladder arrangement (31) in a first vertical direction (D1) and the second ladder arrangement (32) in a second vertical direction (D2) opposite the first vertical direction (D1) as a response to a force (F) applied by the operator on the at least one foothold (311) of S the first ladder arrangement (31); and © the actuator arrangement (33) is arranged to move the second ladder = arrangement (32) in the first vertical direction (D1) and the first ladder arrangement = (31) in the second vertical direction (D2) as a response to a force (F) applied by the i 25 operator on the at least one foothold (321) of the second ladder arrangement (32). 3

S 2. Alifting device according to claim 1,characterized inthatthe & actuator arrangement (33) is an electric motor, a hydraulic actuator, or a pneumatic actuator.

3. A lifting device according to any one of the preceding claims, characterized inthat the lifting device (30) comprises a first force detector (37) connected to the first ladder arrangement (31), a second force detector (38) connected to the second ladder arrangement (32), and control device (39) connected to the first force detector (37), to the second force detector (38), and to the actuator arrangement (33); the first force detector (37) is arranged to detect the force applied by the operator on the at least one foothold (311) of the first ladder arrangement (31); the second force detector (38) is arranged to detect the force applied by the operator on the at least one foothold (321) ofthe second ladder arrangement (32); and the control device (39) is arranged to control the operation of the actuator arrangement (33) based on the force detected by the first force detector (37) or the second force detector (38).

4. A lifting device according to any one of the preceding claims, characterized in that the distance between the lower terminal position and the upper terminal position is 10 to 30 cm.

5. A lifting device according to any one of the preceding claims, characterized inthat & 20 the first ladder arrangement (31) comprises at least two footholds (311)

N . . . . > spaced apart in the vertical direction; and O o the second ladder arrangement (32) comprises at least two footholds = (321) spaced apart in the vertical direction. E K 00 © 0 0 N O N

6. Alifting device according toclaim5,characterized inthat each two consecutive footholds (311) of the first ladder arrangement (31) are spaced 10 to 30 cm apart; and each two consecutive footholds (321) of the second ladder arrangement (32) are spaced 10 to 30 cm apart.

7. A lifting device according to any one of the preceding claims, characterized inthatthe first vertical direction (D1) is a direction away from the ground (G) and the second vertical direction (D2) is a direction towards the ground (G).

8. A lifting device according to any one of the previous claims, characterized inthat the actuator arrangement (33) is arranged to move the first ladder arrangement (31) from the lower terminal position to the upper terminal position as a response to the application of force F on the at least one foothold (311) of the first ladder arrangement (31) when the first ladder arrangement (31) is in the lower terminal position; the actuator arrangement (33) is arranged to move the first ladder arrangement (31) from the upper terminal position to the lower terminal position as a response to the application of force F on the at least one foothold (311) of the first & 20 ladder arrangement (31) when the first ladder arrangement (31) is in the upper N terminal position; O = the actuator arrangement (33) is arranged to move the second ladder T arrangement (32) from the lower terminal position to the upper terminal position as E: a response to the application of force F on the at least one foothold (321) of the second 5 25 ladder arrangement (32) when the second ladder arrangement (32) is in the lower 3 terminal position; and N the actuator arrangement (33) is arranged to move the second ladder arrangement (32) from the upper terminal position to the lower terminal position as a response to the application of force F on the at least one foothold (321) of the second ladder arrangement (32) when the second ladder arrangement (32) is in the upper terminal position.

9. A lifting device according to any one of claims 1 to 8, characterized in that the lifting device (30) comprises selecting means (40) connected to the actuator arrangement (33) for selecting the first vertical direction (D1) between a direction away from the ground (G) and a direction towards the ground (G).

10. A lifting device according to any one of the preceding claims, characterized in that the lifting device (30) comprises disabling means (41) connected to the actuator arrangement (33) for disabling the operation of the lifting device (30) by the operator.

11. A machine comprising a cabin (10), a machine body (20), and a lifting device (30) according to any one of the preceding claims connected to the machine body (20).

12. A machine according to claim 11, characterized in that the machine (1) is a vehicle, such as a van, a truck, or a tractor; or a stationary machine, such as a crane. O N O N O I o I [an a K 00 © 0 0 N O N