JP7810088B2 - cargo handling vehicle - Google Patents

Description

This invention relates to a cargo handling vehicle.

A known example of prior art for cargo handling vehicles is the autonomous forklift disclosed in Patent Document 1. The autonomous forklift disclosed in Patent Document 1 is equipped with an obstacle detection device at the lower front end. The obstacle detection device has a two-dimensional, planar detection area using laser light and is capable of detecting objects within the detection area. The obstacle detection device has a planar detection area, detects objects within the detection area as obstacles, and outputs a detection signal to a control device. The side of the detection area farther from the autonomous forklift is set as a deceleration area, and the side closer to the autonomous forklift is set as a stopping area.

Japanese Patent Application Laid-Open No. 2019-105995

However, the autonomous forklift disclosed in Patent Document 1 has a problem in that if raindrops, mud, or other debris adheres to the obstacle detection device, the obstacle detection device may mistakenly recognize the debris as an obstacle.

The present invention was made in consideration of the above-mentioned problems, and its object is to provide a cargo handling vehicle that can prevent foreign objects from adhering to obstacle detection sensors that detect obstacles for forward assistance.

In order to solve the above problems, the present invention provides a loading vehicle having a vehicle body, a loading device provided at the front of the vehicle body, and an obstacle detection sensor provided on the loading device for detecting obstacles in front of the vehicle body, wherein the loading device comprises a mast, a lift bracket that can be raised and lowered relative to the mast, and an attachment provided on the lift bracket, wherein the obstacle detection sensor is provided on the mast and has an openable/closeable cover that covers the obstacle detection sensor, the openable/closeable cover is provided on the lift bracket, and when forward assistance is required, the obstacle detection sensor is opened by raising the lift bracket , and when forward assistance is not required, the obstacle detection sensor is covered by the lowered position of the lift bracket .

In this invention, the obstacle detection sensor is provided on the mast, and an openable cover is provided to cover the obstacle detection sensor. The openable cover opens the obstacle detection sensor when forward assistance is required, and covers the obstacle detection sensor when forward assistance is not required. Therefore, except when forward assistance is required, the cover covers the obstacle detection sensor, thereby preventing foreign matter such as raindrops and mud from adhering to the obstacle detection sensor.

Furthermore , since the openable cover is provided on the lift bracket, when the lift bracket is in a lowered position where forward assistance is not required, the openable cover covers the obstacle detection sensor. When the lift bracket is raised and forward assistance is required, the openable cover rises together with the lift bracket, allowing the obstacle detection sensor to detect an obstacle in front of the vehicle body.

In addition, in the above-described cargo handling vehicle, the openable cover may be configured to have a front cover portion disposed in front of the obstacle detection sensor, and an upper cover portion disposed above the obstacle detection sensor.
In this case, the front cover is disposed in front of the obstacle detection sensor, and the upper cover is disposed above the obstacle detection sensor, which prevents foreign matter such as mud flying from the front while the vehicle is moving from adhering to the obstacle detection sensor, as well as preventing foreign matter such as rainwater falling from above from adhering to the obstacle detection sensor.

The present invention also provides a loading vehicle having a vehicle body, a loading device provided at the front of the vehicle body, and an obstacle detection sensor provided on the loading device for detecting obstacles in front of the vehicle body, wherein the loading device comprises a mast, a lift bracket that can be raised and lowered relative to the mast, and an attachment provided on the lift bracket, wherein the obstacle detection sensor is provided on the mast and is provided with an openable/closeable cover that covers the obstacle detection sensor, an actuator that opens and closes the openable/closeable cover, a control device that controls the actuator, and a signal transmitter connected to the control device that emits a signal to open the openable/closeable cover from the obstacle detection sensor, wherein when the control device receives the signal , it controls the actuator to open the openable/closeable cover from the obstacle detection sensor, and the openable/closeable cover opens the obstacle detection sensor when forward assistance is required and covers the obstacle detection sensor when forward assistance is not required .
In the present invention , the actuator opens and closes the openable cover, and when a signal is sent from the signal transmitter for forward assistance, the control device controls the actuator to open the openable cover, so that the openable cover can be released from the obstacle detection sensor by the signal from the signal transmitter.

In addition, in the above-mentioned loading and unloading vehicle, the signal transmitter may be a height sensor that detects the height of the lift bracket, and may be configured to emit the signal when the height detected by the height sensor exceeds a preset threshold value.
In this case, when the height detected by the height sensor exceeds a preset threshold, the height sensor transmits a signal, so that the opening and closing cover can be opened from the obstacle detection sensor by the height of the lift bracket.

In the cargo handling vehicle, the signal transmitter may be an operation button that can be operated by an operator, and the signal may be transmitted when the operation button is operated.
In this case, when the operator operates the operation button, the operation button transmits a signal, so that the openable cover can be opened from the obstacle detection sensor by the operator operating the operation button.

This invention provides a cargo handling vehicle that can prevent foreign objects from adhering to obstacle detection sensors that detect obstacles for forward assistance.

1 is a perspective view of a forklift according to a first embodiment. 1 is a perspective view of a main part of a forklift according to a first embodiment. FIG. 1 is a schematic configuration diagram of a forklift according to a first embodiment. 1A is a diagram showing the opening and closing cover when forward assistance is required, and FIG. 1B is a diagram showing the opening and closing cover when forward assistance is not required. 10A is a diagram showing the opening/closing cover when front assistance is required for the forklift truck according to the second embodiment, and FIG. 10B is a diagram showing the opening/closing cover when front assistance is not required. FIG. 10 is a schematic configuration diagram of a forklift according to a second embodiment. FIG. 10 is a schematic configuration diagram of a forklift according to a third embodiment. FIG. 10 is a schematic configuration diagram of a forklift according to a fourth embodiment.

(First embodiment)
A forklift as a cargo handling vehicle according to a first embodiment will be described below with reference to the drawings. Note that the terms "front/back,""left/right," and "up/down" that specify directions are based on the state in which the forklift operator is seated in the driver's seat and facing the forward direction of the forklift.

As shown in FIG. 1, the forklift 10 is equipped with a load handling device 12 at the front of the vehicle body 11. A driver's seat 13 is provided near the center of the vehicle body 11. Drive wheels 14 are provided at the front of the vehicle body 11, and steerable wheels 15 are provided at the rear of the vehicle body 11. A counterweight 16 is provided at the rear of the vehicle body 11, and is used to adjust the vehicle weight and achieve weight balance within the vehicle body 11. The forklift 10 of this embodiment is an engine forklift. Note that for ease of explanation, the load supported by the load handling device 12 is not shown in FIG. 1.

The vehicle body 11 is provided with a head guard 17 that covers the upper part of the driver's seat 13. A tilt cylinder (not shown) operated by hydraulic oil is installed between the vehicle body 11 and the loading device 12. Operation of the tilt cylinder causes the loading device 12 to tilt in the forward and backward directions with the lower end of the loading device 12 as a fulcrum.

As shown in Figures 1 and 2, the cargo handling apparatus 12 has a pair of left and right outer masts 18. The pair of left and right outer masts 18 are equipped with a pair of left and right inner masts 19 that can be raised and lowered inside the outer masts 18. The inner masts 19 are equipped with lift brackets 21 that rise and fall along the inner masts 19.

The upper ends of the outer masts 18 are connected by outer upper beams 22 (see Figure 1). The lower parts of the outer masts 18 are connected by outer lower beams 23 (see Figures 1 and 2). The outer masts 18, outer upper beams 22, and outer lower beams 23 form a mast. An outer middle beam 24 is provided above the outer lower beams 23, connecting the outer masts 18. A mast support member 25 is attached to the lower rear surface of the outer masts 18. The mast support member 25 is supported by the mast support surface of the front axle (not shown) of the vehicle body 11. The upper ends of the inner masts 19 are connected by inner upper beams 26 (see Figure 1). The lower parts of the inner masts 19 are connected by an inner lower beam (not shown).

The lift bracket 21 allows various attachments to be attached and detached. The lift bracket 21 is equipped with a pair of upper and lower finger bars 28, 29 and a connecting member 30 that connects both ends of the pair of upper and lower finger bars 28, 29. The upper finger bar 28 is the upper finger bar, and the lower finger bar 29 is the lower finger bar. The finger bars 28, 29 are members that respectively engage a pair of left and right forks 31.

The lift bracket 21 is equipped with a pair of left and right forks 31 and a backrest 32. The left and right forks 31 lift up and support the load. The backrest 32 supports the rear of the load supported by the pair of left and right forks 31.

A pair of lift cylinders 33, which are operated by the supply and discharge of hydraulic oil, are installed upright on the outer lower beams 23 of the outer masts 18. The lift cylinders 33 are equipped with a cylinder body 34 and a rod (not shown) that extends and retracts relative to the cylinder body 34. The upper end of the rod is attached to the inner upper beam 26 of the inner mast 19. When the rod of the lift cylinder 33 rises, the inner mast 19 rises relative to the outer mast 18, and the lift bracket 21 rises relative to the inner mast 19.

In this embodiment, an obstacle detection sensor 35 for detecting obstacles ahead of the forklift 10 is provided on the outer lower beam 23 of the outer mast 18. In other words, the obstacle detection sensor 35 is provided on the mast. In this embodiment, the obstacle detection sensor 35 is a laser range finder (LRF: light-wave distance meter). The obstacle detection sensor 35 is a range finder that measures distance by emitting a laser to the surrounding area and receiving light reflected from the area where the laser hits, and can obtain information about the shape of objects present ahead of the forklift 10 as surrounding objects.

In this embodiment, a two-dimensional laser range finder is used that emits a laser while changing the horizontal irradiation angle. The obstacle detection sensor 35 is fixed to the front of the forklift 10 and can scan the laser light horizontally to detect the direction and distance to an object as a point cloud. As shown in Figure 1, a detection range E of the obstacle detection sensor 35 is set.

As shown in FIG. 3, the forklift 10 is equipped with a control device 36 on its body 11. The control device 36 controls each part of the forklift 10. The control device 36 includes a CPU 37 and a storage unit 38 consisting of RAM, ROM, etc. The control device 36 may also include dedicated hardware, such as an application-specific integrated circuit (ASIC), that executes at least some of the various processes. The control device 36 may be configured as a circuit including one or more processors that operate according to a computer program, one or more dedicated hardware circuits such as an ASIC, or a combination thereof. The storage unit 38 stores program code or instructions configured to cause the CPU 37 to execute processes. The storage unit 38 stores various programs for controlling each part of the forklift 10.

In this embodiment, the forklift 10 is equipped with an alarm 39 connected to the control device 36. The alarm 39 is, for example, a display monitor capable of displaying an alarm, or it may be a warning buzzer that emits an alarm sound. The alarm 39 is controlled by the control device 36. When the obstacle detection sensor 35 detects an obstacle in front of the forklift 10, the alarm 39 issues a warning under the control of the control device 36.

In this embodiment, an openable cover 40 is provided to cover the obstacle detection sensor 35. The openable cover 40 is provided to open the obstacle detection sensor 35 when forward assistance is required for the forklift 10, and to cover the obstacle detection sensor 35 when forward assistance is not required. The openable cover 40 is provided on the lift bracket 21, and covers the obstacle detection sensor 35 when the lift bracket 21 is in the lowered position, and opens the obstacle detection sensor 35 when the lift bracket 21 is raised.

The opening/closing cover 40 has a front cover portion 41 positioned in front of the obstacle detection sensor 35, an upper cover portion 42 positioned above the obstacle detection sensor 35, and side cover portions 43 positioned to the sides of the obstacle detection sensor 35. When the lift bracket 21 is lowered to the lowered position, the front cover portion 41 is located in front of the obstacle detection sensor 35, the upper cover portion 42 is close to the top of the obstacle detection sensor 35, and the side cover portions 43 are located on both sides of the obstacle detection sensor 35. Therefore, when the lift bracket 21 is in the lowered position, the opening/closing cover 40 covers the front, top, and left and right sides of the obstacle detection sensor 35, except for the area behind the obstacle detection sensor 35.

The openable cover 40 rises as the lift bracket 21 rises. As the lift bracket 21 rises, the openable cover 40 rises to a height that opens the obstacle detection sensor 35, allowing the laser of the obstacle detection sensor 35 to scan without being blocked by the openable cover 40. In this embodiment, the openable cover 40 opens the obstacle detection sensor 35 when the fork 31 is 50 cm or higher above the ground. The openable cover 40 opens the obstacle detection sensor 35 when forward assistance is required for the forklift 10, and covers the obstacle detection sensor 35 when forward assistance is not required.

Next, the operation of the forklift 10 of this embodiment will be described. When the forklift 10 performs loading and unloading operations, the forks 31 scoop up and support the load. When the forklift 10 travels with the forks 31 supporting a load, depending on the size of the load, the field of vision of the operator of the forklift 10 may be obstructed, and for example, the operator may not be able to fully visually confirm the condition ahead of the forklift 10.

As shown in Figure 4(a), in this embodiment, when the forklift 10 is traveling with the forks 31 at a height above the ground of 50 cm or more, the openable cover 40 opens the obstacle detection sensor 35, and the obstacle detection sensor 35 scans with a laser. When an obstacle is detected within the detection range E of the obstacle detection sensor 35, the control device 36 activates the alarm 39 to issue a warning. The operator of the forklift 10 is aware of the presence of an obstacle ahead of the forklift 10 due to the warning from the alarm 39.

Next, we will explain what happens when the forks 31 are not supporting a load. As shown in Figure 4(b), when the forks 31 are not supporting a load, the lift bracket 21 is lowered to the lowered position. When the lift bracket 21 is in the lowered position, the openable cover 40 covers the front, top, and left and right sides of the obstacle detection sensor 35. This prevents raindrops, muddy water, and other foreign matter from adhering to the obstacle detection sensor 35. Note that for ease of explanation, portions of the openable cover 40 are broken away in Figures 4(a) and 4(b), so only the right side cover portion 43 is shown, but the left side cover portion 43 is not.

Even when the forklift 10 is traveling with the lift bracket 21 lowered to the lowered position, the front cover portion 41 of the openable cover 40 is positioned in front of the obstacle detection sensor 35, protecting the front of the obstacle detection sensor 35 from foreign objects such as mud flying in from the front. Furthermore, the upper cover portion 42 of the openable cover 40 prevents raindrops from adhering to the obstacle detection sensor 35 during rainfall. Note that while the forks 31 are clear of the road surface G when the lift bracket 21 is lowered, the forks 31 can be brought into contact with the ground by further lowering the lift bracket 21.

The forklift 10 of this embodiment has the following advantages.
(1) The obstacle detection sensor 35 is provided on the mast, and an openable cover 40 is provided to cover the obstacle detection sensor 35. The openable cover 40 opens the obstacle detection sensor 35 when forward assistance is required, and covers the obstacle detection sensor 35 when forward assistance is not required. Therefore, except when forward assistance is required, the openable cover 40 covers the obstacle detection sensor 35, thereby preventing foreign matter such as raindrops and mud from adhering to the obstacle detection sensor 35.

(2) Because the openable cover 40 is attached to the lift bracket 21, when the lift bracket 21 is in the lowered position, the openable cover 40 covers the obstacle detection sensor 35. When the lift bracket 21 is raised and forward assistance is required, the openable cover 40 rises along with the lift bracket 21, allowing the obstacle detection sensor 35 to detect an obstacle in front of the vehicle body 11.

(3) The openable cover 40 has a front cover portion 41 that is positioned in front of the obstacle detection sensor 35, and an upper cover portion 42 that is positioned above the obstacle detection sensor 35. This prevents foreign matter such as mud that is blown in from the front while the vehicle is in motion from adhering to the obstacle detection sensor 35. It also prevents foreign matter such as rainwater that falls from above from adhering to the obstacle detection sensor 35.

Second Embodiment
Next, a forklift according to a second embodiment will be described. This embodiment differs from the first embodiment in that the openable cover is opened and closed by an actuator. In this embodiment, the same components as those in the first embodiment will be referred to and the same reference numerals will be used.

As shown in Figures 5(a) and 5(b), the forklift 50 is equipped with an openable cover 51 that covers the obstacle detection sensor 35. The openable cover 51 is box-shaped and is pivotally supported by a support member 52 provided behind the obstacle detection sensor 35. The support member 52 is attached to the outer lower beam 23. The support member 52 is equipped with an actuator 53 that swings the openable cover 51 back and forth to open and close it. In this embodiment, the actuator 53 is an electric motor.

The opening/closing cover 51 has a front cover portion 54, a rear cover portion 55, an upper cover portion 56, and a pair of side cover portions 57. When the opening/closing cover 51 covers the obstacle detection sensor 35, the front cover portion 54 is located in front of the obstacle detection sensor 35, and the rear cover portion 55 is located behind the obstacle detection sensor 35. When the opening/closing cover 51 covers the obstacle detection sensor 35, the upper cover portion 56 is located above the obstacle detection sensor 35, and the pair of left and right side cover portions 57 are located on both the left and right sides of the obstacle detection sensor 35. Note that for ease of explanation, a portion of the opening/closing cover 51 has been cut away in Figures 5(a) and 5(b), so only the right side cover portion 57 is shown, but the left side cover portion 57 is not.

As shown in FIG. 6, the actuator 53 that opens and closes the open/close cover 51 is connected to and controlled by the control device 36. The forklift 50 of this embodiment is equipped with a load sensor 58 for detecting the presence or absence of a load on the forks 31. The load sensor 58 corresponds to a signal transmitter and is connected to the control device 36, and the signal from the load sensor 58 is transmitted to the control device 36. A load threshold is set in advance in the control device 36, and when the load detected by the load sensor 58 is equal to or greater than the threshold, the control device 36 determines that a load is present on the forks 31.

The forklift 50 of this embodiment is equipped with a direction lever (not shown) that can be operated by the operator to switch between forward and reverse. The direction lever can be switched to one of three positions: a forward position, which is switched to when the forklift 10 is moving forward; a reverse position, which is switched to when moving backward; and a neutral position. The direction lever is equipped with a lever sensor 59 that transmits a signal indicating the position of the direction lever to the control device 36. The lever sensor 59 corresponds to a signal transmitter. In this embodiment, when the control device 36 determines that a load is present and receives a signal from the lever sensor 59 indicating that the position of the direction lever is in the forward position, the control device 36 controls the actuator 53 so that the open/close cover 51 opens the obstacle detection sensor 35.

This embodiment achieves the same effects as effects (1) and (3) of the first embodiment. Furthermore, when forward assistance is required, i.e., when the forklift 50 is supporting a load and moving forward, the obstacle detection sensor 35 can be opened from the openable cover 51 to detect obstacles. Regardless of the position of the lift bracket 21, when forward assistance is not required, the openable cover 51 can prevent foreign matter such as raindrops and mud from adhering to the obstacle detection sensor 35.

(Third embodiment)
Next, a forklift according to a third embodiment will be described. This embodiment differs from the first embodiment in that the openable cover is opened and closed by an actuator and in that the openable cover is opened and closed depending on the lift height. Furthermore, some of the configuration of this embodiment, including the openable cover, is the same as that of the second embodiment. In this embodiment, the same configuration as that of the first and second embodiments will be referred to, and the same reference numerals will be used.

As shown in Figure 7, the forklift 60 of this embodiment is equipped with a height sensor 61 that detects the height of the lift bracket 21, and the height sensor 61 corresponds to a signal transmitter. The signal from the height sensor 61 is transmitted to the control device 36. A height threshold is set in advance in the control device 36, and when the height detected by the height sensor 61 is equal to or greater than the threshold, the control device 36 controls the actuator 53 to open the opening/closing cover 51. The height threshold is set in advance in the control device 36, but the threshold can also be changed.

When the height detected by the height sensor 61 is below the threshold, the openable cover 51 covers the obstacle detection sensor 35, and the openable cover 40 prevents raindrops, mud, and other foreign matter from adhering to the obstacle detection sensor 35. When the height detected by the height sensor 61 is above the threshold, the openable cover 51 opens the obstacle detection sensor 35, and the obstacle detection sensor 35 detects obstacles in front of the forklift 50 by scanning with laser light.

This embodiment achieves the same effects as effects (1) and (3) of the first embodiment. Furthermore, the lift height threshold can be changed, and the openable cover 40 can prevent foreign objects from adhering to the obstacle detection sensor 35 depending on the environment in which the forklift 60 is used.

(Fourth embodiment)
Next, a forklift according to a fourth embodiment will be described. This embodiment differs from the first embodiment in that an openable cover is opened and closed by an operator. Furthermore, some of the configuration of this embodiment, including the openable cover, is the same as that of the second embodiment. In this embodiment, the same configuration as that of the first and second embodiments will be referred to and the same reference numerals will be used.

As shown in FIG. 8 , the forklift 70 of this embodiment is equipped with an open/close operation button 71 for opening and closing the open/close cover 51. The open/close operation button 71 corresponds to a signal transmitter. The signal from the open/close operation button 71 is transmitted to the control device 36. The open/close operation button 71 may be provided, for example, on a loading/unloading lever (lift lever, tilt lever, etc.) or on an instrument panel (not shown). When the operator presses the open/close operation button 71, the control device 36 transmits a signal to the control device 36. In response to the signal from the open/close operation button 71, the control device 36 controls the actuator 53 to open the open/close cover 51. The open/close cover 51 can be released from the obstacle detection sensor 35 by the operator operating the operation button 71.

The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the invention. For example, the following modifications may be made:

The first openable cover described above includes a front cover, an upper cover, and a pair of side cover portions, but is not limited to this. For example, the openable cover may include only a front cover portion, or may include only a front cover portion and an upper cover portion.
Although the second cover is described as being opened and closed by swinging back and forth by an actuator, this is not limited to this. The cover may be opened and closed by moving up and down or reciprocating. Furthermore, the actuator for opening and closing the cover may be a means other than an electric motor or a hydraulic cylinder.

10, 50, 60, 70 Forklift (cargo handling vehicle)
REFERENCE SIGNS LIST 11 Vehicle body 12 Load handling device 18 Outer mast 19 Inner mast 21 Lift bracket 23 Outer lower beam 31 Fork 33 Lift cylinder 35 Obstacle detection sensor 36 Control device 39 Warning device 40, 51 Opening and closing cover 41, 54 Front cover portion 42, 56 Upper cover portion 43, 57 Side cover portion 53 Actuator 55 Rear cover portion 58 Load sensor 59 Lever sensor 61 Lift height sensor 71 Operation button

Claims (5)

The car body and
a loading device provided at the front of the vehicle body;
an obstacle detection sensor provided in the cargo handling device for detecting an obstacle in front of the vehicle body,
The cargo handling device is a cargo handling vehicle including a mast, a lift bracket that can be raised and lowered relative to the mast, and an attachment provided on the lift bracket,
the obstacle detection sensor is provided on the mast;
an opening/closing cover for covering the obstacle detection sensor;
The opening/closing cover is provided on the lift bracket, and when forward assistance is required, the opening/closing cover opens the obstacle detection sensor by raising the lift bracket , and when forward assistance is not required, the opening/closing cover covers the obstacle detection sensor by lowering the lift bracket . The opening and closing cover is
a front cover portion disposed in front of the obstacle detection sensor;
2. The cargo handling vehicle according to claim 1 , further comprising an upper cover portion disposed above the obstacle detection sensor . The car body and
a loading device provided at the front of the vehicle body;
an obstacle detection sensor provided in the cargo handling device for detecting an obstacle in front of the vehicle body,
The cargo handling device is a cargo handling vehicle including a mast, a lift bracket that can be raised and lowered relative to the mast, and an attachment provided on the lift bracket,
the obstacle detection sensor is provided on the mast;
an opening/closing cover for covering the obstacle detection sensor;
an actuator that opens and closes the open/close cover;
a control device for controlling the actuator;
a signal transmitter connected to the control device and configured to transmit a signal for opening the openable cover from the obstacle detection sensor,
When the control device receives the signal, the control device controls the actuator to open the openable cover from the obstacle detection sensor,
The cargo handling vehicle is characterized in that the openable cover opens the obstacle detection sensor when front assistance is required, and covers the obstacle detection sensor when front assistance is not required . 4. The loading vehicle according to claim 3, wherein the signal transmitter is a height sensor that detects the height of the lift bracket, and transmits the signal when the height detected by the height sensor exceeds a preset threshold value . 4. The cargo handling vehicle according to claim 3 , wherein the signal transmitter is an operation button operable by an operator, and transmits the signal when the operation button is operated.