Patent Description:
<CIT> discloses a steering device used to steer a vehicle. The steering device includes an annular rib. The steering device further includes a rotation central portion having the rotation axis of the steering device and a steering unit connected to the rotation central portion. The rib has an annular shape that includes the rotation central portion in plan view of the steering device in the extending direction of the rotation axis of the rotation central portion.

To allow a vehicle operator to drive comfortably, the space around the driver's seat needs to be wide. Examples of widening the space around the driver's seat include reducing the size of the steering device. However, the reduction of the steering device in size necessitates a decrease in the diameter of the annular rib. In the above-described steering device including the annular rib, the diameter of the rib needs to be greater than that of the rotation central portion. Thus, reducing the size of the steering device is difficult.

<CIT> discloses a steering device according to the preamble of claim <NUM>.

It is the object of the invention to provide a steering device having a reduced size and minimally obstructing a line of sight.

The object of the invention is achieved with a steering device according to claim <NUM>. Further advantageous developments of the invention are subject-matter of the dependent claims.

As an advantage of the steering device according to the invention, as compared with when the steering unit includes an annular rib, the width of the entire steering device is reduced. Accordingly, the steering device of the present disclosure has a smaller size than the steering device including the annular rib.

A steering device <NUM> and an industrial vehicle <NUM> according to an embodiment will now be described. The steering device <NUM> of the present embodiment is mounted on the industrial vehicle <NUM>. The "front," "rear," "left," and "right" in the following description refer to the front, rear, left, and right of the industrial vehicle <NUM>, respectively.

As shown in <FIG>, the industrial vehicle <NUM> (vehicle) is a counterbalance forklift. The industrial vehicle <NUM> uses electric power as a power source. The industrial vehicle <NUM> includes a cargo handling device <NUM>, a vehicle body <NUM>, two driven wheels <NUM>, two steered wheels <NUM>, an overhead guard <NUM>, four pillars <NUM>, a driver's seat <NUM>, foot pedals <NUM>, a battery hood <NUM>, a control circuit <NUM>, a cargo handling operation unit <NUM>, a steering column <NUM>, and the steering device <NUM>.

The cargo handling device <NUM> includes a mast <NUM> extending in the up-down direction, forks <NUM> that can be lifted and lowered together with the mast <NUM>, and a lift cylinder <NUM> that lifts and lowers the forks <NUM>. The forks <NUM> are loaded with cargo. The lift cylinder <NUM> is a hydraulic cylinder. As the lift cylinder <NUM> extends and contracts so as to lift and lower the mast <NUM>, the forks <NUM> are lifted and lowered.

The vehicle body <NUM> is located behind the mast <NUM>.

The two driven wheels <NUM> are located at the lower front part of the vehicle body <NUM>. The two driven wheels <NUM> are spaced apart from each other in the left-right direction.

The two steered wheels <NUM> are located at the lower rear part of the vehicle body <NUM>. The two steered wheels <NUM> are adjacent to each other.

The overhead guard <NUM> is located above the vehicle body <NUM>.

The four pillars <NUM> connect the vehicle body <NUM> to the overhead guard <NUM>. The pillars <NUM> extend from the corners of the vehicle body <NUM> toward the overhead guard <NUM>, respectively.

The driver's seat <NUM> is mounted on the vehicle body <NUM>. More specifically, the driver's seat <NUM> is located between the vehicle body <NUM> and the overhead guard <NUM>. An operator of the industrial vehicle <NUM> sits on the driver's seat <NUM>. Thus, the driver's seat <NUM> is located in a driver's cabin V. In the present embodiment, the driver's cabin V is a space surrounded by the vehicle body <NUM>, the overhead guard <NUM>, and the four pillars <NUM>. To facilitate understanding, the operator of the industrial vehicle <NUM> is hereinafter simply referred to as the operator.

The foot pedals <NUM> are located in front of the driver's seat <NUM>. Thus, the foot pedals <NUM> are located in the lower front part of the driver's cabin V. The foot pedals <NUM> includes an accelerator pedal and a brake pedal. When the foot pedals <NUM> are operated, the industrial vehicle <NUM> travels.

The battery hood <NUM> is a wall that defines a battery accommodation portion and the driver's cabin V and can be opened and closed. The battery accommodation portion accommodates a battery which is a power source of the industrial vehicle <NUM>. The battery is, for example, a rechargeable battery. Examples of the rechargeable battery include a lithium-ion rechargeable battery and a lead-acid battery. The battery hood <NUM> is located below the driver's seat <NUM>. The operator opens the battery hood <NUM> by, for example, bringing down the driver's seat <NUM> rearward. The operator takes the battery out of the battery accommodation portion by opening the battery hood <NUM>.

The control circuit <NUM> includes a processor and a memory. Examples of the processor include a central processing unit (CPU), a graphics processing unit (GPU), and a digital signal processor (DSP). The memory includes a random access memory (RAM) and a read-only memory (ROM). The memory stores program codes or instructions configured to cause the processor to execute processes. The memory, or computer readable medium, includes any type of medium that is accessible by general-purpose computers or dedicated computers. The control circuit <NUM> may include a hardware circuit such as an application-specific integrated circuit (ASIC) or a field-programmable gate array (FPGA). The control circuit <NUM>, which is a processing circuit, may include one or more processors that run according to a computer program, one or more hardware circuits (e.g., ASIC or FPGA), or a combination thereof.

The control circuit <NUM> obtains information related to traveling operation and information related to cargo handling operation. Examples of the information related to traveling operation include the travel speed of the industrial vehicle <NUM>, the directions of the steered wheels <NUM>, and the remaining battery life. Examples of the information related to cargo handling operation include a cargo weight, the heights of the forks <NUM>, and a tilt angle.

The cargo handling operation unit <NUM> is used to operate the cargo handling device <NUM>. In the present embodiment, the cargo handling operation unit <NUM> includes multiple (more specifically, three) levers. The cargo handling operation unit <NUM> may be of a button type or a handle type. The cargo handling operation unit <NUM> is located at the front right part of the driver's cabin V. In the present embodiment, the industrial vehicle <NUM> travels and performs cargo handling when operated by the operator.

The steering column <NUM> extends from the front part of the driver's cabin V toward the driver's seat <NUM>. In other words, the steering column <NUM> is located at a position forward of the driver's seat <NUM> (more specifically, at a position in front of the driver's seat <NUM>). The cargo handling operation unit <NUM> is located on the right side of the steering column <NUM>. The steering column <NUM> includes an angle sensor (not shown). The angle sensor detects the rotation angle of the steering device <NUM>. The orientation of each steered wheel <NUM> is changed based on the detection result of the angle sensor.

The steering device <NUM> has a ringless shape without an annular rib. The steering device <NUM> is connected to the steering column <NUM>. The steering device <NUM> is used to steer the industrial vehicle <NUM>.

The steering device <NUM> will now be described in detail.

Referring to <FIG>, the operator rotates the steering device <NUM> with respect to a rotation axis Ax of the steering device <NUM> so as to change the orientation of each steered wheel <NUM>. This allows the operator to adjust the travel direction of the industrial vehicle <NUM>. To facilitate understanding, the rotation axis Ax of the steering device <NUM> is hereinafter simply referred to as the rotation axis Ax. The extending direction of the rotation axis Ax is referred to as the axial direction z. Further, "in plan view of the steering device <NUM> in the axial direction z" may be simply referred to as "in plan view in the axial direction z. " The steering device <NUM> includes a rotation central portion <NUM> and a steering unit <NUM>.

As shown in <FIG>, the rotation central portion <NUM> is circular in plan view in the axial direction z. The rotation central portion <NUM> includes a fixed portion <NUM>, a rotation portion <NUM>, and a display <NUM>.

As shown in <FIG>, the fixed portion <NUM> is columnar. The fixed portion <NUM> extends in the axial direction z. The fixed portion <NUM> is capable of being fixed to the steering column <NUM>. The center axis of the fixed portion <NUM> coincides with the rotation axis Ax.

The rotation portion <NUM> is rotatable relative to the fixed portion <NUM> with respect to the rotation axis Ax. The rotation axis of the rotation portion <NUM> coincides with the rotation axis Ax. The rotation portion <NUM> includes an end wall <NUM> and a circumferential wall <NUM>.

The end wall <NUM> has a disk shape in which its thickness direction coincides with the axial direction z. The center of the end wall <NUM> overlaps the rotation axis Ax in plan view in the axial direction z. The end wall <NUM> includes an insertion hole 53a through which the fixed portion <NUM> is inserted. The end wall <NUM> is a connection end that is connected to the industrial vehicle <NUM>. The fixed portion <NUM> is connected to the steering column <NUM> through the insertion hole 53a of the end wall <NUM> so as to connect the steering device <NUM> to the industrial vehicle <NUM>.

The circumferential wall <NUM> extends in the axial direction z from the outer circumference of the end wall <NUM>. The circumferential wall <NUM> includes a connection circumferential wall <NUM> and a protruding circumferential wall <NUM>.

The protruding circumferential wall <NUM> is tubular. The protruding circumferential wall <NUM> extends from an end of the connection circumferential wall <NUM> in the axial direction z. In the axial direction z, this end is located opposite an end of the connection circumferential wall <NUM> to which the end wall <NUM> is connected. The protruding circumferential wall <NUM> is connected to the end wall <NUM> by the connection circumferential wall <NUM>. The protruding circumferential wall <NUM> includes an end 56a located opposite the connection circumferential wall <NUM> in the axial direction z. This end is hereinafter referred to as the opening end 56a. The opening end 56a is circular in plan view in the axial direction z.

An outer circumferential surface 56b of the protruding circumferential wall <NUM> is farther from the rotation axis Ax than an outer circumferential surface 55a of the connection circumferential wall <NUM>. The outer circumferential surface 56b of the protruding circumferential wall <NUM> is inclined to become closer to the rotation axis Ax as the outer circumferential surface 56b becomes farther from the end wall <NUM> in the axial direction z.

The end wall <NUM> and the inner circumferential wall of the circumferential wall <NUM> define an accommodation recess <NUM>. The accommodation recess <NUM> accommodates at least part of the fixed portion <NUM>.

A rotation mechanism RF is disposed between the fixed portion <NUM> and the rotation portion <NUM>. The rotation mechanism RF allows the rotation portion <NUM> to rotate relative to the fixed portion <NUM>. The rotation mechanism RF is, for example, a planetary gear mechanism. Instead, the rotation mechanism RF may be a bearing mechanism or may be a sliding mechanism using lubricating oil.

The display <NUM> is a display device that can be seen from the driver's seat <NUM>. The display <NUM> displays a display content such as the information related to the traveling state or cargo handling state of the industrial vehicle <NUM>. The display <NUM> displays the display content based on, for example, an instruction from the control circuit <NUM>.

The display <NUM> is accommodated in the accommodation recess <NUM>. In the present embodiment, the display <NUM> is fixed to the fixed portion <NUM>. The display <NUM> is circular in plan view in the axial direction z. More specifically, the display <NUM> has a disk shape perpendicular to the rotation axis Ax. The center of the display <NUM> coincides with the center of the rotation central portion <NUM> in plan view in the axial direction z. In other words, the center of the display <NUM> overlaps the rotation axis Ax in plan view in the axial direction z.

The steering unit <NUM> pivots about the rotation axis Ax of the rotation central portion <NUM>. The steering unit <NUM> is connected to the rotation central portion <NUM>. The steering unit <NUM> is fixed to the rotation portion <NUM>. This allows the operator to rotate the rotation portion <NUM> by operating the steering unit <NUM>. In plan view in the axial direction z, the steering unit <NUM> protrudes from the rotation central portion <NUM> in a radial direction y. The radial direction y is one of the directions that are perpendicular to the axial direction z. The direction that is perpendicular to the axial direction z and the radial direction y is hereinafter referred to as the width direction x.

When the protruding direction of the steering unit <NUM>, namely, the radial direction y is parallel to the left-right direction of the industrial vehicle <NUM>, the steering unit <NUM> is located at a neutral position. When the steering unit <NUM> is located at the neutral position, the rotation angle of the steering device <NUM> is <NUM>°.

The steering unit <NUM> includes an arm <NUM> and a grip <NUM>.

In plan view in the axial direction z, the arm <NUM> extends from the rotation central portion <NUM> (more specifically, protruding circumferential wall <NUM>) in the radial direction y. In plan view in the axial direction z, the arm <NUM> is U-shaped. In plan view in the axial direction z, the arm <NUM> opens toward the rotation central portion <NUM>. The arm <NUM> opens in the radial direction y toward the rotation axis Ax. The arm <NUM> includes two connection side portions <NUM>, <NUM> (first connection side portion <NUM> and second connection side portion <NUM>) and a merge side portion <NUM>.

The connection side portions <NUM>, <NUM> extend in a curved manner. The cross-section of each of the connection side portions <NUM>, <NUM> is a cross-section of a local surface in which the extending curve of the connection side <NUM>, <NUM> is a normal. The connection side portion <NUM> includes a first end 72a, a second end 72b, a connection inner surface 72c, and a connection outer surface 72d. The connection side portion <NUM> includes a first end 73a, a second end 73b, a connection inner surface 73c, and a connection outer surface 73d.

The first ends 72a, 73a are connected to the rotation portion <NUM>. More specifically, the first ends 72a, 73a are connected to the protruding circumferential wall <NUM>. In plan view in the axial direction z, the first ends 72a, 73a are spaced apart from each other in the width direction x.

In plan view in the axial direction z, the connection side portions <NUM>, <NUM> extend in the radial direction y from the rotation portion <NUM>. More specifically, in plan view in the axial direction z, the connection side portions <NUM>, <NUM> extend in the radial direction y from the protruding circumferential wall <NUM>, to which the first ends 72a, 73a are fixed.

The connection inner surface 72c is one of the surfaces of the connection side portion <NUM>. The connection inner surface 73c is one of the surfaces of the connection side portion <NUM>. The connection inner surface 72c and the connection inner surface 73c face each other in the width direction x. Thus, the connection side portions <NUM>, <NUM> are spaced apart from each other in the width direction x. The connection inner surfaces 72c, 73c are connected to the outer circumferential surface 56b of the protruding circumferential wall <NUM>.

In plan view of the steering device <NUM> in the width direction x, the connection side portions <NUM>, <NUM> overlap each other. As the connection side portions <NUM>, <NUM> become farther from the rotation axis Ax in the radial direction y, the connection side portions <NUM>, <NUM> extend so as to become farther from the end wall <NUM> of the rotation portion <NUM>. Thus, the distance between the arm <NUM> and the end wall <NUM> in the axial direction z increases as the distance from the rotation central portion <NUM> in the radial direction y increases. The first connection side portion <NUM> includes an inflection point between the first end 72a and the second end 72b. The first connection side portion <NUM> includes an inflection point between the first end 73a and the second end 73b. At each inflection point, the curvature in the axial direction z is <NUM>.

The connection outer surface 72d is located opposite the connection inner surface 72c in the width direction x. The connection outer surface 73d is located opposite the connection inner surface 73c in the width direction x. In plan view in the axial direction z, the connection outer surfaces 72d, 73d define the outer edge of the arm <NUM>. The distance between the connection outer surface 72d and the connection outer surface 73d in the width direction x decreases as the distance from the rotation central portion <NUM> (more specifically, rotation axis Ax) in the radial direction y increases. Thus, the width of the arm <NUM> decreases as the arm <NUM> becomes farther from the rotation central portion <NUM> in the radial direction y. The width of a member refers to the length of the member in the width direction x. When the width of a member differs depending on the position, the maximum width of the entire member is referred to as the maximum width.

The merge side portion <NUM> is a member to which the second ends 72b, 73b are connected. The merge side portion <NUM> is an end of the arm <NUM> extending in the radial direction y. The merge side portion <NUM> is a tip of the arm <NUM> located opposite the rotation central portion <NUM>. The merge side portion <NUM> is an end of the arm <NUM> separated from the rotation central portion <NUM> in the radial direction y. The merge side portion <NUM> includes a merge inner surface 74a and a merge outer surface 74b.

The merge inner surface 74a is one of the surfaces of the merge side portion <NUM>. The merge inner surface 74a connects the connection inner surface 72c to the connection inner surface 73c. The merge inner surface 74a faces the outer circumferential surface 56b of the protruding circumferential wall <NUM>. In plan view in the axial direction z, the connection inner surfaces 72c, 73c and the merge inner surface 74a define a notch. The notch and the outer circumferential surface 56b of the protruding circumferential wall <NUM> define a through portion <NUM>. The through portion <NUM> extends through the steering unit <NUM> (more specifically, arm <NUM>) in the axial direction z. Thus, the steering unit <NUM> includes the through portion <NUM>. Further, the arm <NUM> includes the through portion <NUM>.

The merge outer surface 74b is located opposite the merge inner surface 74a at least in the radial direction y. The merge outer surface 74b connects the connection outer surface 72d to the connection outer surface 73d. In plan view in the axial direction z, the merge outer surface 74b is the outer edge of the arm <NUM>. In the present embodiment, the connection outer surface 72d, 73d and the merge outer surface 74b define the outer edge of the arm <NUM> in plan view in the axial direction z.

The width of the merge side portion <NUM> is less than or equal to a maximum width W2 of the rotation central portion <NUM>. The maximum width of the merge side portion <NUM> is equal to the distance between the second ends 72b, 73b in the width direction x. Thus, a maximum width W1 of the arm <NUM> is equal to the distance between the connection outer surfaces 72d, 73d in the width direction x. The maximum width W1 of the arm <NUM> is less than the maximum width W2 of the rotation central portion <NUM>. The width of the arm <NUM> decreases from the rotation central portion <NUM> toward the merge side portion <NUM>. The maximum width W1 of the arm <NUM> may be equal to the maximum width W2 of the rotation central portion <NUM>. That is, the maximum width W1 of the arm <NUM> only needs to be less than or equal to the maximum width W2 of the rotation central portion <NUM>. In the present embodiment, the maximum width W2 of the rotation central portion <NUM> is equal to the diameter of the outer circle of the protruding circumferential wall <NUM> of the rotation central portion <NUM>.

The grip <NUM> is held by the operator to operate the steering device <NUM>. In plan view in the axial direction z, the grip <NUM> is circular. The maximum width of the grip <NUM> is less than or equal to the maximum width W2 of the rotation central portion <NUM>. The width of the grip <NUM> is less than the maximum width W1 of the arm <NUM>. The grip <NUM> of the present embodiment is a knob that generally has the shape of an oval sphere. The maximum width of the grip <NUM> is equal to the diameter of the grip <NUM> in plan view in the axial direction z.

The grip <NUM> is connected to the arm <NUM>. More specifically, the grip <NUM> is connected to the merge side portion <NUM>. Thus, the width of the arm <NUM> decreases from the rotation central portion <NUM> toward the grip <NUM>.

The grip <NUM> extends from the arm <NUM> so as to become farther from the end wall <NUM>. More specifically, the grip <NUM> extends in the axial direction z from the merge side portion <NUM>. The grip <NUM> extends at least in the axial direction z so as to become farther from the end wall <NUM>. The grip <NUM> is rotatable about its rotation axis relative to the arm <NUM>. The rotation axis of the grip <NUM> is parallel to the axial direction z. More specifically, the grip <NUM> is connected to the arm <NUM> by a rotation mechanism. The rotation mechanism may be, for example, a planetary gear mechanism, a bearing mechanism, or a sliding mechanism. In plan view in the axial direction z, the grip <NUM> protrudes from the merge side portion <NUM> in the radial direction y. The diameter of the grip <NUM> is less than the maximum width W1 of the arm <NUM>. Thus, the maximum width of the steering unit <NUM> is the maximum width W1 of the arm <NUM>. To facilitate understanding, the maximum width of the steering unit <NUM> in the present embodiment may be referred to as the maximum width W1.

The larger one of the maximum width W1 of the steering unit <NUM> and the maximum width W2 of the rotation central portion <NUM> is a maximum width W3 of the entire steering device <NUM>. Since the maximum width W1 of the steering unit <NUM> is less than the maximum width W2 of the rotation central portion <NUM>, the maximum width W3 of the entire steering device <NUM> is the maximum width W2 of the rotation central portion <NUM>.

Relationship between Steering Device <NUM> and Industrial Vehicle <NUM>.

The surroundings of the steering device <NUM> in the driver's cabin V will now be described. The distance from the rotation axis Ax to the grip <NUM> is referred to as the protruding length R. The protruding length R is an indicator that indicates the degree to which the steering unit <NUM> of the steering device <NUM> protrudes in the radial direction y.

As shown in <FIG>, the maximum width W3 of the entire steering device <NUM> is less than the protruding length R of the steering device <NUM>. Thus, when, in particular, the steering device <NUM> is located at the neutral position, the steering device <NUM> does not overlap the front side of the driver's seat <NUM>. This improves the operator's visibility of the front side. Further, the rotation central portion <NUM> is circular in plan view in the axial direction z. Thus, even if the steering device <NUM> is rotated, the shape of the rotation central portion <NUM> changes slightly. This improves the visibility of the steering device <NUM>. Furthermore, the cargo handling operation unit <NUM> is located on the right side of the steering device <NUM> and located closer to the operator than the steering device <NUM>. This allows the operator to operate the cargo handling operation unit <NUM> with the right hand while operating the steering device <NUM> with the left hand.

As shown in <FIG>, in the industrial vehicle <NUM>, a distance D1 between the steering device <NUM> and the driver's seat <NUM> needs to be greater than a certain distance for the battery hood <NUM> to be opened. The distance D1 indicates how wide the driver's cabin V is. In the present embodiment, when the steering device <NUM> is located at the neutral position, the distance between the steering device <NUM> and the driver's seat <NUM> is the maximum. Thus, the distance D1 between the steering device <NUM> and the driver's seat <NUM> can be increased by adjusting the position of the steering unit <NUM>.

A case where the industrial vehicle <NUM> includes a ring-shaped steering device <NUM> instead of the steering device <NUM> of the present embodiment will now be described with reference to <FIG>. The components of the ring-shaped steering device <NUM> that correspond to those of the steering device <NUM> are given the same reference numbers, and will not be described. The protruding length of the ring-shaped steering device <NUM> and the protruding length R of the steering device <NUM> of the present embodiment are equal to each other and thus both referred to as the protruding length R to facilitate understanding.

The steering unit <NUM> of the ring-shaped steering device <NUM> includes the arm <NUM> and the grip <NUM>. The arm <NUM> of the ring-shaped steering device <NUM> includes an annular rib <NUM>. The rib <NUM> is located at the tip of a portion of the arm <NUM> that extends from the rotation central portion <NUM>.

In plan view in the axial direction z, the center of the rib <NUM> overlaps the rotation axis Ax. In plan view in the axial direction z, the rotation central portion <NUM> is located in the rib <NUM>. That is, the diameter of the rib <NUM> is greater than that of the rotation central portion <NUM>. Thus, the rib <NUM> defines the outer edge of the ring-shaped steering device <NUM> in plan view in the axial direction z. Accordingly, if the thickness of the rib <NUM> is ignored, the width of the ring-shaped steering device <NUM> coincides with the diameter of the rib <NUM>. Therefore, the width of the ring-shaped steering device <NUM> corresponds to the maximum width W1 of the steering unit <NUM>.

The steering performance of the steering devices <NUM>, <NUM> is determined by the torque of the rotation central portion <NUM> relative to a force applied to the grip <NUM> by the operator. The relationship between the force and the torque is determined by the distance from the rotation central portion <NUM> to the grip <NUM> in the radial direction y (determined by the radius of the rib <NUM> in the ring-shaped steering device <NUM> of the comparative example).

The distance D1 between the steering device <NUM>, <NUM> and the driver's seat <NUM> is determined by the maximum width W3 of the entire steering device <NUM>, <NUM>. Thus, the space around the driver's seat <NUM> can be increased by reducing the maximum width W3 of the entire steering device <NUM>, <NUM>.

However, in the ring-shaped steering device <NUM>, a decrease in the diameter of the rib <NUM> decreases the distance from the rotation central portion <NUM> to the rib <NUM> (grip <NUM>), namely, the protruding length R of the ring-shaped steering device <NUM>. Thus, a change in the diameter of the rib <NUM> (more specifically, a decrease in the diameter of the rib <NUM>) adversely affects the steering performance of the industrial vehicle <NUM>. This makes it difficult to reduce the size of the ring-shaped steering device <NUM> and improve the steering performance of the ring-shaped steering device <NUM>.

Referring to <FIG>, for example, the industrial vehicle <NUM> including the ring-shaped steering device <NUM> has a lower visibility of the front side from the driver's seat <NUM> than the industrial vehicle <NUM> including the steering device <NUM> of the present embodiment.

Referring to <FIG>, the industrial vehicle <NUM> including the ring-shaped steering device <NUM> has a shorter distance D1 between the ring-shaped steering device <NUM> and the driver's seat <NUM> than the industrial vehicle <NUM> including the steering device <NUM> of the present embodiment. Thus, the operator needs to widen the distance D1 between the ring-shaped steering device <NUM> and the driver's seat <NUM> by, for example, tilting the steering column <NUM> upward.

The operation of the present embodiment will now be described.

As shown in <FIG>, in plan view in the axial direction z, the steering device <NUM> of the present embodiment includes the arm <NUM> of the steering unit <NUM> protruding in the radial direction y. The grip <NUM> is disposed at an end of the arm <NUM>. The maximum width W1 of the steering unit <NUM> is less than the maximum width W2 of the rotation central portion <NUM> (see <FIG>). The maximum width W3 of the entire steering device <NUM> is the maximum width W2 of the rotation central portion <NUM>.

As shown in <FIG>, the maximum width W3 of the entire ring-shaped steering device <NUM> in the comparative example is the maximum width W1 of the steering unit <NUM> (more specifically, rib <NUM>), which is greater than the maximum width W2 of the rotation central portion <NUM>. Thus, the maximum width W3 of the entire steering device <NUM> in the present embodiment is less than the maximum width W3 of the entire ring-shaped steering device <NUM> in the comparative example.

The advantages of the present embodiment will now be described.

In this structure, the industrial vehicle <NUM> is provided with a high visibility of the front side.

Particularly, in the industrial vehicle <NUM> (e.g., forklift), the forks <NUM> are loaded with cargo. Thus, the operator needs to see the cargo in front of the industrial vehicle <NUM>. Accordingly, when the vehicle operated by the operator is the industrial vehicle <NUM>, broadening the front field of view of the operator is particularly important. The steering device <NUM> has a smaller size than the ring-shaped steering device <NUM>. Therefore, the steering device <NUM> is less likely to obstruct the operator's front field of view than the ring-shaped steering device <NUM> and thus broadens the operator's front field of view.

In some cases, the industrial vehicle <NUM> includes the battery hood <NUM> below the driver's seat <NUM> like the forklift of the present embodiment. The use of the ring-shaped steering device <NUM> requires time and effort to, for example, move the steering column <NUM> in order to increase the distance D1 between the ring-shaped steering device <NUM> and the driver's seat <NUM>. When the industrial vehicle <NUM> includes the steering device <NUM> of the present embodiment, the distance D1 between the steering device <NUM> and the driver's seat <NUM> is increased so that the time and effort to open the battery hood <NUM> is saved.

The present embodiment may be modified as follows. The present embodiment and the following modifications can be combined as long as the combined modifications remain technically consistent with each other.

The grip <NUM> does not have to be rotatable relative to the arm <NUM>. For example, the grip <NUM> may be fixed to the arm <NUM>. The grip <NUM> does not need to have a knob shape. For example, the grip <NUM> may be columnar or spherical.

The arm <NUM> may have any shape. The arm <NUM> is not limited to U-shaped and may be, for example, V-shaped or O-shaped. The arm <NUM> may extend horizontally from the rotation portion <NUM> in the radial direction y. Alternatively, the width of the arm <NUM> may be fixed or may increase as the arm <NUM> becomes farther from the rotation central portion <NUM> in the radial direction y. In short, as long as the maximum width W1 of the steering unit <NUM> is less than or equal to the maximum width W2 of the rotation central portion <NUM>, the steering unit <NUM> may have any shape.

The number of through portions <NUM> is not limited to one and may be two or more.

The through portion <NUM> may have any shape (e.g., circular hole or quadrilateral hole). The through portion <NUM> may extend through the arm <NUM> and the grip <NUM> in the axial direction z.

In plan view in the axial direction z, the display <NUM> does not have to be circular. For example, in plan view in the axial direction z, the display <NUM> may have a polygonal shape or may have a combination of geometrical shapes.

The number of displays <NUM> is not limited to one and may be two or more. The display <NUM> does not have to display information related to the industrial vehicle <NUM> and may display any content.

The display <NUM> does not have to be fixed to the fixed portion <NUM>. For example, the display <NUM> may be fixed to the rotation portion <NUM>. In this structure, the display <NUM> is rotatable integrally with the rotation portion <NUM>. Thus, the display <NUM> is rotatable integrally with the steering unit <NUM>. In this structure, the display <NUM> rotates together with the steering unit <NUM>. This allows the operator to easily see the rotation angle of the steering device <NUM> from the appearance of the display <NUM>. Thus, the operator easily operates the steering device <NUM>.

In this modification, the control circuit <NUM> may prevent the display content of the display <NUM> from rotating as the display <NUM> rotates.

As shown in <FIG>, the industrial vehicle <NUM> includes, for example, a gyro sensor <NUM>. The gyro sensor <NUM> measures the angular velocity of the steering device <NUM>.

The control circuit <NUM> obtains the angular velocity of the steering device <NUM> from the gyro sensor <NUM>. Based on the obtained result, the control circuit <NUM> obtains the rotation angle of the steering device <NUM>. The rotation angle of the steering device <NUM> indicates the displacement of the steering device <NUM> from the neutral position.

Then, based on the obtained result, the control circuit <NUM> obtains a rotation state of the display <NUM> (i.e., a rotation state of the steering device <NUM>). Examples of the rotation state include the rotation angle and angular velocity of the display <NUM>.

Subsequently, based on the obtained rotation state, the control circuit <NUM> rotates the display content of the display <NUM> so as to cancel the rotation of the display <NUM>. For example, the control circuit <NUM> rotates the display content by the rotation angle of the display <NUM> in a direction opposite the rotation direction of the display <NUM>.

In such a configuration, even if the display <NUM> rotates integrally with the steering unit <NUM>, rotation of the display content from the operator's point of view is prevented. This allows the operator to easily check the display content.

The rotation central portion <NUM> may have any shape. For example, the rotation central portion <NUM> may have a tubular shape without the protruding circumferential wall <NUM> or may have a quadrilateral tubular shape.

The rotation central portion <NUM> does not have to include the fixed portion <NUM>. In other words, the entire steering device <NUM> may be rotatable with respect to the rotation axis Ax.

The industrial vehicle <NUM> does not have to be driven by electric power. For example, the industrial vehicle <NUM> may be driven by an internal combustion engine or may be driven by hydrogen and oxygen. The industrial vehicle <NUM> is not limited to a forklift and may be, for example, a towing tractor or a tractor.

The vehicle in which the steering device <NUM> is disposed is not limited to an industrial vehicle and may be, for example, a passenger car.

Various changes in form and details may be made to the examples above without departing from the scope of the claims. The examples are for the sake of description only, and not for purposes of limitation. Descriptions of features in each example are to be considered as being applicable to similar features or aspects in other examples. Suitable results may be achieved if sequences are performed in a different order, and/or if components in a described system, architecture, device, or circuit are combined differently, and/or replaced or supplemented by other components or their equivalents. All variations within the scope of the claims are included in the disclosure.

Claim 1:
A steering device (<NUM>) used to steer a vehicle (<NUM>), the steering device (<NUM>) comprising:
a rotation central portion (<NUM>) that includes a rotation axis (Ax) of the steering device (<NUM>); and
a steering unit (<NUM>) that is connected to the rotation central portion (<NUM>), wherein
a direction in which the rotation axis (Ax) of the rotation central portion (<NUM>) extends is referred to as an axial direction (z),
one of directions that are perpendicular to the axial direction (z) is referred to as a radial direction (y),
a direction that is perpendicular to the axial direction (z) and the radial direction (y) is referred to as a width direction (x),
the steering unit (<NUM>) protrudes from the rotation central portion (<NUM>) in the radial direction (y) in plan view of the steering device (<NUM>) in the axial direction (z),
a maximum width of the steering unit (<NUM>) in the width direction (x) is less than or equal to a maximum width of the rotation central portion (<NUM>) in the width direction (x),
the steering unit (<NUM>) includes an arm (<NUM>) and a grip (<NUM>) in plan view of the steering device (<NUM>) in the axial direction (z), the arm (<NUM>) extending from the rotation central portion (<NUM>) in the radial direction (y), and the grip (<NUM>) being connected to a tip (<NUM>) of the arm (<NUM>) and extending at least in the axial direction (z), and
the tip (<NUM>) is an end of the arm (<NUM>) located opposite the rotation central portion (<NUM>),
the steering device (<NUM>) being characterized in that
the arm (<NUM>) includes a through portion (<NUM>) that extends through the arm (<NUM>) in the axial direction (z).