Patent Description:
Conventionally, there has been known a picking truck equipped with a vehicle approach notification device including a first illumination portion and a second illumination portion (see, for example, Patent Literature <NUM>: <CIT>). The first illumination portion is provided on a cab capable of elevation in a vehicle, and irradiates a first notification light toward a road surface behind the vehicle when an elevation position of the cab is lower than a predetermined threshold value, that is, at low lifting height. On the other hand, the second illumination portion is provided on a vehicle body incapable of elevation in the vehicle, and irradiates a second notification light toward the road surface behind the vehicle when an elevation position of the cab is equal to or higher than a threshold value, that is, at high lifting height. According to this vehicle approach notification device and the picking truck, in the case of high lifting height in which the first notification light from the first illumination portion is not delivered to the road surface sufficiently, the second illumination portion irradiates the second notification light toward the road surface instead of the first illumination portion, thereby reliably notifying a person in the vicinity of approach of a vehicle.

However, in the above-described conventional vehicle approach notification device and the picking truck, the first illumination portion or the second illumination portion is turned on even when notification to the rear of the vehicle is unnecessary, so it cannot be said to be efficiently power-saving.

The invention has been made in view of the above circumstances, and an object of the invention is to provide an vehicle approach notification device and a picking truck that have the same notification effect as that of a conventional device but are more power efficient than the conventional device.

The following description serves a better understanding of the present invention. In order to solve the above problems, a first vehicle approach notification device according to the invention includes a first illumination portion for mounting in a cab capable of elevation in a vehicle and irradiating a first notification light toward a road surface behind the vehicle; a second illumination portion for mounting on a vehicle body incapable of elevation in the vehicle and irradiating a second notification light toward the road surface; and a control unit controlling a lighting state of the first illumination portion and the second illumination portion according to a travel state of the vehicle body and an elevation position of the cab. The control unit (<NUM>) turns on or blinks the first illumination portion and turns off the second illumination portion when the vehicle approach notification device (<NUM>) is mounted on the vehicle, the travel state is backward travel and the elevation position is lower than a predetermined threshold value; (<NUM>) turns off the first illumination portion and turns on or blinks the second illumination portion when the vehicle approach notification device (<NUM>) is mounted on the vehicle, the travel state is backward travel or travel stop and the elevation position is equal to or higher than the threshold value; and (3A) turns off the first illumination portion and the second illumination portion when the vehicle approach notification device (<NUM>) is mounted on the vehicle, the travel state is forward travel.

Moreover, in order to solve the above problems, a second vehicle approach notification device according to the invention includes a first illumination portion for mounting in a cab capable of elevation in a vehicle and irradiating a first notification light toward a road surface behind the vehicle; a second illumination portion for mounting on a vehicle body incapable of elevation in the vehicle and irradiating a second notification light toward the road surface; and a control unit controlling a lighting state of the first illumination portion and the second illumination portion according to a travel state of the vehicle body and an elevation position of the cab. The control unit (<NUM>) turns on or blinks the first illumination portion and turns off the second illumination portion when the vehicle approach notification device (<NUM>) is mounted on the vehicle, the travel state is backward travel and the elevation position is lower than a predetermined threshold value; (<NUM>) turns off the first illumination portion and turns on or blinks the second illumination portion when the vehicle approach notification device (<NUM>) is mounted on the vehicle, the travel state is backward travel or travel stop and the elevation position is equal to or higher than the threshold value; and (3B) turns off the first illumination portion and the second illumination portion when the vehicle approach notification device (<NUM>) is mounted on the vehicle, the travel state is travel stop and the elevation position is lower than the threshold value.

Preferably, the control unit of the first and second vehicle approach notification device (2A) turns off the first illumination portion and turns on the second illumination portion when the travel state is backward travel and the elevation position is equal to or higher than the threshold value; and (2B) turns off the first illumination portion and blinks the second illumination portion when the travel state is travel stop and the elevation position is equal to or higher than the threshold value.

Preferably, the first illumination portion and the second illumination portion of the first and second vehicle approach notification devices are provided such that axes of the first notification light and the second notification light intersect on the road surface when the vehicle approach notification device (<NUM>) is mounted on the vehicle and the elevation position is equal to the threshold value.

Preferably, a color of the second notification light of the first and second vehicle approach notification devices is different from a color of the first notification light.

In order to solve the above problems, a first picking truck according to the invention includes a vehicle body including a travel device; a mast provided behind the vehicle body; a cab capable of elevation along the mast; a first illumination portion provided in the cab and irradiating a first notification light toward a road surface behind a vehicle; a second illumination portion provided on the vehicle body and irradiating a second notification light toward the road surface; and a control unit controlling a lighting state of the first illumination portion and the second illumination portion according to a travel state of the vehicle body and an elevation position of the cab. The control unit (<NUM>) turns on or blinks the first illumination portion and turns off the second illumination portion when the travel state is backward travel and the elevation position is lower than a predetermined threshold value; (<NUM>) turns off the first illumination portion and turns on or blinks the second illumination portion when the travel state is backward travel or travel stop and the elevation position is equal to or higher than the threshold value; and (3A) turns off the first illumination portion and the second illumination portion when the travel state is forward travel.

Moreover, in order to solve the above problems, a second picking truck according to the invention includes a vehicle body including a travel device; a mast provided behind the vehicle body; a cab capable of elevation along the mast; a first illumination portion provided in the cab and irradiating a first notification light toward a road surface behind a vehicle; a second illumination portion provided on the vehicle body and irradiating a second notification light toward the road surface; and a control unit controlling a lighting state of the first illumination portion and the second illumination portion according to a travel state of the vehicle body and an elevation position of the cab. The control unit (<NUM>) turns on or blinks the first illumination portion and turns off the second illumination portion when the travel state is backward travel and the elevation position is lower than a predetermined threshold value; (<NUM>) turns off the first illumination portion and turns on or blinks the second illumination portion when the travel state is backward travel or travel stop and the elevation position is equal to or higher than the threshold value; and (3B) turns off the first illumination portion and the second illumination portion when the travel state is travel stop and the elevation position is lower than the threshold value.

Preferably, the control unit of the first and second picking trucks (2A) turns off the first illumination portion and turns on the second illumination portion when the travel state is backward travel and the elevation position is equal to or higher than the threshold value; and (2B) turns off the first illumination portion and blinks the second illumination portion when the travel state is travel stop and the elevation position is equal to or higher than the threshold value.

The first illumination portion of the first and second picking trucks may be provided on a head guard of the cab.

The first illumination portion and the second illumination portion of the first and second picking trucks are preferably provided such that axes of the first notification light and the second notification light intersect on the road surface when the elevation position is equal to the threshold value.

Preferably, a color of the second notification light for the first and second picking tracks is different from a color of the first notification light.

According to the invention, it is possible to provide an vehicle approach notification device and a picking truck that have the same notification effect as that of a conventional device but are more power efficient than the conventional device.

Hereinafter, embodiments of a vehicle approach notification device and a picking truck according to the invention will be described with reference to the accompanying drawings.

<FIG> shows a picking truck <NUM> according to an embodiment of the invention. As shown in the drawing, the picking truck <NUM> according to this embodiment includes a vehicle body <NUM> having a travel device, legs <NUM>, <NUM> aligned left and right and a mast <NUM> provided at the rear of the vehicle body <NUM>; and a cab <NUM> capable of elevation along the mast <NUM>. The cab <NUM> includes an operation panel <NUM> including various levers operated by an operator, a fall guard <NUM> for preventing the operator from falling; a pair of left and right forks <NUM>, <NUM> extending rearward; and a head guard <NUM> that covers an operator's head. The forks <NUM>, <NUM> are provided on a floor plate of the cab <NUM>.

The picking truck <NUM> according to this embodiment further includes a control unit <NUM>, a first illumination portion <NUM>, and a second illumination portion <NUM> which constitute a vehicle approach notification device <NUM>; an elevation position detection portion <NUM>; and a travel state detection portion <NUM>.

The first illumination portion <NUM> is composed of an LED light that irradiates a first notification light L1 toward a road surface F behind the vehicle. An image of the first notification light L1 appearing on the road surface F may be circular with an ambiguous outline, or it may be spot-shaped, line-shaped, or arrow-shaped with a clear outline by the action of lens or slit provided in the first illumination portion <NUM>. Moreover, the color of the first notification light L1 is preferably a color that stands out against the road surface F in order to enhance the notification effect. In this embodiment, the color of the first notification light L1 is blue.

The first illumination portion <NUM> is provided at a rear end of the head guard <NUM> via a suitable bracket (not shown). The first illumination portion <NUM> is provided such that its irradiation direction (that is, an axis of the first notification light L1) forms an angle θ1 with respect to a vertical line P.

The second illumination portion <NUM> is composed of an LED light that irradiates a second notification light L2 toward the road surface F behind the vehicle. Similar the image of the first notification light L1, an image of the second notification light L2 appearing on the road surface F may be circular with an ambiguous outline, or it may be spot-shaped, line-shaped, or arrow-shaped with a clear outline. Also, the color of the second notification light L2 is preferably a color that stands out against the road surface F, and more preferably different from the color of the first notification light L1 in order to enhance the notification effect. In this embodiment, the color of the second notification light L2 is red.

The second illumination portion <NUM> is provided behind the vehicle body <NUM> via a suitable bracket (not shown). The second illumination portion <NUM> is provided such that its irradiation direction (that is, an axis of the second notification light L2) forms an angle θ2 with respect to the vertical line P (where θ2>θ1).

As shown in <FIG>, the control unit <NUM> is configured to change the lighting states of the first illumination portion <NUM> and the second illumination portion <NUM> according to an elevation position H of the cab <NUM> detected by the elevation position detection portion <NUM> and a travel state of the vehicle body <NUM> detected by the travel state detection portion <NUM>.

Note that although the control unit <NUM> is provided inside the vehicle body <NUM> as shown <FIG>, the position of the control unit <NUM> may be changed arbitrarily. For example, the control unit <NUM> may be provided in the cab <NUM>. Moreover, in <FIG>, the elevation position detection portion <NUM> and the travel state detection portion <NUM> are provided inside the vehicle body <NUM>, but their positions may also be changed arbitrarily.

The operation of the picking truck <NUM> and the vehicle approach notification device <NUM> according to this embodiment will be described in more detail with reference to <FIG>, <FIG> and <FIG>.

In this case, the control unit <NUM> turns on or blinks the first illumination portion <NUM> (turns on in this embodiment) and turns off the second illumination portion <NUM>. As a result, a blue image by the first notification light L1 appears on the road surface F. Moreover, an example of "when the elevation position H is lower than a threshold value Hth" is when the elevation position H is equal to a lower limit value Hmin, as shown in (A) of <FIG>.

A distance D1 from tips of the forks <NUM>, <NUM> to a center of the image of the first notification light L1 is referred to as a "first irradiation distance". As shown in (C) of <FIG>, a first irradiation distance D1 changes according to the elevation position H. More specifically, the first irradiation distance D1 becomes longer as the elevation position H becomes higher.

In this embodiment, the threshold value Hth is <NUM>. The threshold value Hth is set to a value such that the second notification light L2 is not blocked by the cab <NUM> when the elevation position H is equal to the threshold value Hth.

In this case, the control unit <NUM> turns off the first illumination portion <NUM> and turns on or blinks the second illumination portion <NUM> (turns on in this embodiment). As a result, a red image by the second notification light L2 appears on the road surface F.

A distance D2 from the tips of the forks <NUM>, <NUM> to a center of the image of the second notification light L2 is referred to as a "second irradiation distance". In this embodiment, the threshold value Hth and the angles θ1 and θ2 are determined such that the first irradiation distance D1 and a second irradiation distance D2 are equal (see <FIG> and <FIG> of <NUM>) when the elevation position H is equal to the threshold value Hth. That is, in this embodiment, axes of the first notification light L1 and the second notification light L2 intersect on the road surface F when the elevation position H is equal to the threshold value Hth. As a result, it is possible to prevent the image of the notification light from instantaneously moving when the elevation position H becomes equal to the threshold value Hth, thereby preventing a person in the vicinity from losing sight of the image.

As shown in (C) of <FIG>, according to the picking truck <NUM> and the vehicle approach notification device <NUM> of this embodiment, the second irradiation distance D2 does not change even if the elevation position H changes between the threshold value Hth and an upper limit Hmax. Thus, according to the picking truck <NUM> and the vehicle approach notification device <NUM> of this embodiment, there will always be sufficient notification light delivered to the road surface F. In other words, according to the picking truck <NUM> and the vehicle approach notification device <NUM> of this embodiment, it is possible to prevent a decrease in the notification effect in the case of high lifting height.

Further, according to the picking truck <NUM> and the vehicle approach notification device <NUM> of this embodiment, the color of the image appearing on the road surface F changes according to the elevation position H. While the operator of the picking truck <NUM> tends to be less aware of people around him in the case of high lifting height, according to the picking truck <NUM> and the vehicle approach notification device <NUM> of this embodiment, people in the surroundings will become aware of the high lifting height based on the color of the image appearing on the road surface F and be more cautious of the surroundings, thereby preventing contact with the picking truck <NUM> by themselves.

In this case, the control unit <NUM> turns off the first illumination portion <NUM> and the second illumination portion <NUM> regardless of the elevation position H (see (A) of <FIG>). As a result, the power consumption in the first illumination portion <NUM> and the second illumination portion <NUM> becomes substantially zero.

Since the first illumination portion <NUM> and the second illumination portion <NUM> are configured to irradiate light to the road surface F behind the vehicle, they hardly contribute to preventing contact between the picking truck <NUM> traveling forward and a person in the vicinity. Thus, turning off the first illumination portion <NUM> and the second illumination portion <NUM> at forward travel for the purpose of reducing power consumption does not affect the notification effect.

Also in this case, the control unit <NUM> turns off the first illumination portion <NUM> and the second illumination portion <NUM> (see (B) of <FIG>). As a result, the power consumption in the first illumination portion <NUM> and the second illumination portion <NUM> becomes substantially zero.

There is a low possibility that a person in the vicinity will come into contact with the picking truck <NUM> that is at travel stop. That is, there is little need to turn on the first illumination portion <NUM> and the second illumination portion <NUM> at travel stop. Thus, turning off the lights of the first illumination portion <NUM> and the second illumination portion <NUM> at travel stop for the purpose of reducing power consumption does not affect the notification effect.

In this case, the control unit <NUM> turns off the first illumination portion <NUM> and turns on or blinks (in this embodiment, turns on) the second illumination portion <NUM> (see (B) of <FIG>). As a result, a red image by the second notification light L2 appears on the road surface F.

As described above, there is a low possibility that a person in the vicinity will come into contact with the picking truck <NUM> that is at travel stop. However, when anyone in the vicinity should happen to come into contact with the picking truck <NUM> in the case of high lifting height, the cab <NUM> may shake and the operator working at height may be in danger of falling. In other words, the need for notification is higher in the case of high lifting height than in the case of low lifting height. This is the reason why the second illumination portion <NUM> is turned on even if the vehicle is at travel stop.

To summarize (<NUM>) to (<NUM>), the control unit <NUM> controls the lighting states of the first illumination portion <NUM> and the second illumination portion <NUM> as shown in the table below.

Thus, according to the picking truck <NUM> and the vehicle approach notification device <NUM> of this embodiment, by turning off both or one of the first illumination portion <NUM> and the second illumination portion <NUM> within a range in which the notification effect does not decrease, power consumption in the first illumination portion <NUM> and the second illumination portion <NUM> can be reduced.

The embodiment of the vehicle approach notification device and the picking truck according to the invention has been described above, but the configuration of the invention is not limited thereto.

For example, in the invention, when the travel state is travel stop and the elevation position H is equal to or higher than the threshold value Hth, it is preferable that the second illumination portion <NUM> operates in a lighting state different from the case where the travel state is backward travel and the elevation position H is equal to or higher than the threshold value Hth. For example, in the case where the second illumination portion <NUM> is turned on when the travel state is backward travel and the elevation position H is equal to or higher than the threshold value Hth, the second illumination portion <NUM> is preferably blinking when the travel state is travel stop and the elevation position H is equal to or higher than the threshold value Hth, as shown in Table <NUM> and <FIG>. According to this configuration, it is possible to notify a person in the vicinity whether the vehicle is at travel stop or at backward travel. Other examples of different lighting states of the second illumination portion <NUM> include turning on light with different colors, blinking with different frequencies, and the like.

Moreover, in the invention, the first illumination portion <NUM> may be provided at any position on the cab <NUM>.

Further, in the invention, when the elevation position H is equal to the threshold value Hth, the first irradiation distance D1 and the second irradiation distance D2 do not necessarily have to match.

Also, the color (blue) of the first notification light L1 and the color (red) of the second notification light L2 described above are merely examples. For example, in the invention, the colors of the first notification light L1 and the second notification light L2 may be the same.

Claim 1:
A vehicle approach notification device (<NUM>), comprising:
a first illumination portion (<NUM>) for mounting in a cab (<NUM>) capable of elevation in a vehicle and for irradiating a first notification light (L1) toward a road surface (F) behind the vehicle when the vehicle approach notification device (<NUM>) is mounted on the vehicle;
a second illumination portion (<NUM>) for mounting on a vehicle body (<NUM>) incapable of elevation in the vehicle and for irradiating a second notification light (L2) toward the road surface (F) behind the vehicle when the vehicle approach notification device (<NUM>) is mounted on the vehicle; and
a control unit (<NUM>) for controlling a lighting state of the first illumination portion (<NUM>) and the second illumination portion (<NUM>) according to a travel state of the vehicle body (<NUM>) and an elevation position (H) of the cab (<NUM>),
wherein the vehicle approach notification device (<NUM>) is characterized in that
the control unit (<NUM>) is configured such that
it turns on or blinks the first illumination portion (<NUM>) and turns off the second illumination portion (<NUM>) when the travel state is backward travel and the elevation position (H) is lower than a predetermined threshold value;
it turns off the first illumination portion (<NUM>) and turns on or blinks the second illumination portion (<NUM>) when the travel state is backward travel or travel stop and the elevation position (H) is equal to or higher than the threshold value; and
it turns off the first illumination portion (<NUM>) and the second illumination portion (<NUM>) when the travel state is forward travel.