Patent ID: 12241438

DETAILED DESCRIPTION

Reference is made below in detail to the embodiments of the disclosure, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. This specification does not describe all elements of the disclosed embodiments and detailed descriptions of what is well known in the art or redundant descriptions on substantially the same configurations have been omitted. The terms ‘part’, ‘module’, ‘member’, ‘block’ and the like as used in the specification may be implemented in software or hardware. Further, a plurality of ‘part’, ‘module’, ‘member’, ‘block’ and the like may be embodied as one component. It is also possible that one ‘part’, ‘module’, ‘member’, ‘block’ and the like includes a plurality of components.

Throughout the specification, when an element is referred to as being “connected to” another element, it may be directly or indirectly connected to the other element and the “indirectly connected to” includes being connected to the other element via a wireless communication network.

Also, it is to be understood that the terms “include” and “have” are intended to indicate the existence of elements disclosed in the specification, and are not intended to preclude the possibility that one or more other elements may exist or may be added.

Throughout the specification, when a member is located “on” another member, this includes not only when one member is in contact with another member but also when another member is present between the two members.

The terms first, second, primary, secondary, and the like are used to distinguish one component from another component, and the component is not limited by the terms described above.

An expression used in the singular encompasses the expression of the plural, unless it has a clearly different meaning in the context.

The reference numerals used in operations are used for descriptive convenience and are not intended to describe the order of operations and the operations may be performed in a different order unless otherwise stated.

When a component, device, element, or the like of the present disclosure is described as having a purpose or performing an operation, function, or the like, the component, device, or element should be considered herein as being “configured to” meet that purpose or to perform that operation or function.

Hereinafter, embodiments of the disclosure are described in detail with reference to the accompanying drawings.

FIG.1shows a configuration of a forklift to which an engine intake device10for forklift according to an exemplary embodiment of the disclosure is applied.

As shown inFIGS.1and2, a forklift is provided with a body frame1of a vehicle (e.g., forklift) on which an engine is installed, and a mast assembly2may be mounted on a front side of the body frame1.

The mast assembly2may include a mast rail2adisposed in a vertical direction, and a carriage2bthat moves upward and downward along the mast rail2a.

The carriage2bmay move up and down along a chain installed on the mast rail2a, and a pair of forks3for lifting a load is mounted on a front side of the carriage2b, the width therebetween being adjustable from side to side.

Front and rear wheels4aand4bmay be disposed on the front and rear sides of the body frame1, respectively, and a seat of a driver5may be located on an upper portion of the body frame1. An overhead guard6may be installed above the driver's seat5to protect the driver.

An exhaust manifold (not shown) and an intake manifold (not shown) may be installed in the engine, and an exhaust pipe (not shown) and an intake pipe20to guide exhaust and intake air may be connected to the exhaust manifold and the intake manifold, respectively.

An air cleaner (not shown) may be interposed between the intake pipe20and the intake manifold to filter the intake air guided to the intake manifold.

Furthermore, a counterweight7may be mounted on a rear side of the body frame1. The counterweight7may be disposed on an upper portion side of the rear wheel4b.

The counterweight7may serve to shift the center of gravity of a load, which is concentrated at the front side of a body of the vehicle, to the rear side, so that the load may be stably transported and lifted and lowered. The counterweight7may include a weight body8, and a cover9made of a resin material that covers the weight body8.

On the other hand, as shown inFIGS.2to4, the counterweight7is provided with an intake flow path30that passes through the counterweight7, and the intake pipe20may be connected to the intake flow path30to supply the intake air guided through the intake flow path30to the engine. The intake pipe20may be coupled to the counterweight7such that its inlet is connected to an outlet32aof the intake flow path30passing through the counterweight7.

The intake flow path30may be provided to have a polygonal cross-section, such as a circle or a rectangle.

The intake flow path30and the intake pipe20, together with an air cleaner (not shown) and an intake manifold (not shown), may form the engine intake device10for forklifts that provides the intake air to the engine.

The intake flow path30may form an intake channel together with the intake pipe20, and an inlet31aof the intake flow path30may form an entrance to the intake channel.

Accordingly, the intake flow path30formed in the counterweight7may increase a distance between the entrance of the intake channel and the driver's seat5by moving the entrance of the intake channel toward a rear side of the driver's seat5. As a result, the intake noise transmitted from the entrance of the intake channel to the driver's seat5may be reduced.

In addition, the counterweight7, which is equipped with the intake flow path30and serves as a sound barrier, may increase a diffraction attenuation value of the intake noise and increase the sound insulation effect by mass effect, thereby preventing the intake noise from being transmitted to the driver's seat5.

In addition, the intake flow path30formed in the counterweight7may increase a flow passage of intake air so that intake air with sufficiently reduced noise is supplied to the engine, thereby contributing to reduce the intake noise generated by the engine.

Considering the typical shape of the counterweight7, which is formed with a longer length in a width direction of the forklift than the length in a traveling direction of the forklift, it may be desirable to provide the inlet31aof the intake flow path30on a side of the counterweight7so that the intake flow path30may be elongated on the counterweight7along the width direction of the forklift.

The outlet32aof the intake flow path30may be formed at a front side of the counterweight7to facilitate guiding the intake air to the engine disposed at the front side.

The intake flow path30may be formed so that at least the inlet31aside is inclined toward the ground to prevent foreign substances, such as rainwater from entering the intake flow path30.

The intake flow path30may include an inlet section31extending a predetermined length from the inlet31ainto the counterweight7, and an outlet section32bent and extending from the inlet section31toward the outlet32a. The inlet section31on which the inlet31ais formed may be entirely inclined downward toward the ground to prevent foreign substances from entering.

The weight body8of the counterweight7may be made of casting. When the weight body8is prepared by casting, the intake flow path30may be provided integrally with the weight body8in the moulding of the weight body8by adding a structure for forming the intake flow path30to a mould for casting the weight body8.

In the intake flow path30, the cover9side of the counterweight7may be provided integrally with the cover9in the moulding of the cover9by machining a hole in the injection-molded cover9or by adding a structure to the mould for injection moulding the cover such that a hole corresponding to the cross-sectional shape of the intake flow path30is formed.

The method of manufacturing the weight body8or moulding the intake flow path30is not limited to the method described above. The intake flow path30may be prepared by applying various moulding methods depending on the manufacturing method of the weight body8in consideration of the moulding efficiency.

For example, the weight body8may be provided by filling the inside of a metal box with heavy materials, such as slag or mercury, and the intake flow path30may be provided in the weight body8by machining additional holes in the manufactured weight body8.

Furthermore, the engine intake device10for forklifts may further include a branch flow path40that branches off from a midpoint of the intake flow path30so as to communicate with the intake flow path30and extends to an outer surface of the counterweight7, and a cap50that closes at least a portion of the branch flow path40so as to form a resonance chamber60for reducing intake noise passing through the intake flow path30.

The resonance chamber60is designed to reduce flow noise of intake air flowing along the intake flow path30, and may be provided such that its resonance frequency matches the noise frequency of the intake flow path30.

The cap50may be inserted from the outside of the counterweight7into the branch flow path40to block communication between the branch flow path40and the outside of the counterweight7.

The cap50may be manufactured separately from the weight body8and assembled to be inserted into the branch flow path40.

As shown inFIG.5, the cap50may be inserted at an adjustable insertion depth into a distal end of an extension direction of the branch flow path40from the outside of the counterweight7.

Accordingly, the resonance frequency of the resonance chamber60may vary depending on an insertion position of the cap50inserted into the branch flow path40.

As a result, by adjusting the insertion position of the cap50inserted into the branch flow path40to tune the resonance frequency of the resonance chamber60to match the noise frequency of the intake flow path30, the effect of reducing intake noise by the resonance chamber60may be increased.

As shown inFIG.6, the resonance frequency of the resonance chamber60may be adjusted through a length of the cap50inserted into the branch flow path40.

For example, the cap50is inserted into the branch flow path40such that one end in a longitudinal direction of the cap50is aligned with the end in the extension direction of the branch flow path40, but the length of the cap50closing the branch flow path40may be varied. This may allow the resonance frequency of the resonance chamber60and the noise frequency of the intake flow path30to be tuned to match.

At this time, an end surface of the cap50exposed to the outside of the counterweight7may be treated so that no step is formed between the end surface of the cap50and the outer surface of the counterweight7therearound, thereby preventing the resonance chamber60from impairing the aesthetics of the appearance of the counterweight7.

The branch flow path40may be provided integrally with the weight body8when moulding the weight body8together with the intake flow path30, or may be machined to communicate with the intake flow path30in the moulded weight body80.

In addition, in the branch flow path40, the cover9side of the counterweight7may be provided integrally with the cover9in the moulding of the cover9by machining a hole in the injection-molded cover9or by adding a structure to the mould for injection moulding the cover such that a hole corresponding to the cross-sectional shape of the branch flow path40is formed.

On the other hand, if the frequency of the intake noise corresponds to a relatively low frequency, it may be necessary to form a somewhat longer length of the resonance chamber60in order to increase the attenuation effect of the intake noise.

To this end, as shown inFIGS.7and8, the branch flow path40may be provided with a bending section41to ensure a longer length of the resonance chamber60.

At this time, the end surface of the cap50exposed to the outside of the counterweight7is also treated so that no step is formed between the end surface of the cap50and the outer surface of the counterweight7therearound, thereby preventing the resonance chamber60from impairing the aesthetics of the appearance of the counterweight7.

As shown inFIG.8, when the outer surface of the counterweight7around the cap50has a curved shape, the end surface of the cap50may have a curved shape with the same curvature as the outer surface of the counterweight7, so that the end surface of the cap50may match the outer surface of the counterweight7therearound.

Also, as shown inFIG.9, the intake flow path30may be provided with a sound-absorbing material70on its inner surface to improve sound-absorbing performance.

The sound-absorbing material70may be made of foam-based resin or fabric-based fabric and may be attached to the inner surface of the intake flow path30.

Furthermore, as shown inFIG.10, the inner surface of the intake flow path30may be roughened. For example, the inner surface of the intake flow path30may be roughened to form an uneven surface30a.

The rough surface-treated inner surface of the intake flow path30may induce a flow of fluid such that the fluid passing through the intake flow path30creates turbulence, thereby increasing the flow resistance of the fluid. As a result, the flow noise of the fluid may be reduced.

As is apparent from the above, various embodiments of the present disclosure may provide the engine intake device for forklifts capable of improving visibility for the driver and a safety for pedestrians while considering power consumption.

Although embodiments of the disclosure have been shown and described, it would be appreciated by those having ordinary skill in the art that changes may be made in these embodiments without departing from the principles and spirit of the disclosure, the scope of which is defined in the claims and their equivalents.