Patent Description:
Attachments to lift trucks can be added to a standard carriage that normally carries the lifting forks. Some attachments can include a scale to measure a load of a lift truck scale. However, additional attachments can reduce the lift capacity of the lift truck, and make removal and/or repair of the scale difficult.

Accordingly, there is a need for an attachment to be mounted to a lift truck that simplifies sensor arrangements and that is easy to install, remove, and repair. <CIT> relates to a forklift scale attachment. <CIT> relates to a reduced load offset loss integrated lift truck attachment.

Disclosed is a lift truck attachment system that includes a lift truck weighing device with a carriage mounted scale configured to support load handling fixtures and to be secured to a lift truck carriage. In particular, the weighing device includes one or more sensors arranged at a mounting interface between the lift truck carriage and the carriage mounted scale. In disclosed examples, the lift truck weighing device includes one or more of rails, plates, and/or mounting brackets, as a list of non-limiting examples, arranged at the interface with the one or more sensors, which measure a load from the load handling fixtures.

These and other features and advantages of the present invention will be apparent from the following detailed description, in conjunction with the appended claims.

The benefits and advantages of the present invention will become more readily apparent to those of ordinary skill in the relevant art after reviewing the following detailed description and accompanying drawings, wherein:.

The present disclosure describes a lift truck attachment system that includes a lift truck weighing device with a carriage mounted scale configured to support load handling fixtures and to be secured to a lift truck carriage. In particular, the weighing device includes one or more sensors arranged at a mounting interface between the lift truck carriage and the carriage mounted scale. In disclosed examples, the lift truck weighing device includes one or more of rails, plates, and/or mounting brackets, as a list of non-limiting examples, arranged at the interface with the one or more sensors, which measure a load from the load handling fixtures.

The disclosed lift truck attachment system provides advantages over conventional lift truck designs by enabling devices (i.e. a carriage mounted scale, a side-shifter, etc.) to be attached to the lift truck via a weighing device assembly, as well as no or a minimal loss in lifting capacity due to reduction of redundant or unnecessary parts. In contrast to conventional designs, the disclosed lift truck weighing systems have eliminated the requirements for redundant parts that were included to address one or more regulatory standards. These extra parts cause the lifting capacity to be de-rated due to the extra weight, as well as an extended distance of the attachment.

In disclosed examples, a lift truck carriage comprising one or more rails, each rail comprising a fixture mount to support one or more load handling fixtures and a base portion to house a sensor configured to measure forces on the one or more rails from the one or more load handling fixtures.

In some examples, the one or more load handling fixtures are mounted to a plate supported by the one or more rails. In examples, the one or more rails is removably secured to the lift truck carriage.

In some examples, the fixture mount has a void at an interface between the base portion and the fixture mount, the void being aligned with the load sensor. In examples, two or more support brackets configured to secure the one or more rails in a fixed orientation, and arranged between a pair of masts of a lift truck.

In some examples, the one or more rails comprises a first and a second rail, the first rail oriented within the support brackets such that a first fixture mount of the first rail is arranged above a first base portion housing a first load sensor. In examples, the second rail is oriented within the support brackets such that a second fixture mount of the second rail is arranged laterally to a second base portion housing a second load sensor.

In some examples, the second fixture mount is oriented facing opposite a lift truck.

In disclosed examples, a lift truck weighing device comprising a loading plate configured to support one or more load handling fixtures, the loading plate comprising one or more openings arranged between two or more fasteners configured to secure the loading plate to a lift truck carriage, wherein the one or more openings to house a load sensor configured to measure forces on the loading plate from the one or more load handling fixtures.

In some examples, the one or more openings are arranged between two or more fasteners configured to secure the loading plate to a mounting plate. In examples, another fastener secures the mounting plate to the lift truck carriage. In examples, the one or more openings extends through the mounting plate.

In some examples, the load sensor is a strain gauge.

In disclosed examples, a lift truck weighing device comprising a loading plate configured to support one or more load handling fixtures; a mounting plate configured to secure the lift truck weighing device to a lift truck carriage; one or more sensor plates arranged between the loading plate and the mounting plate, the one or more sensor plates being secured to the loading plate at a first portion and secured to the mounting plate at a second portion; and one or more sensors arranged on the one or more sensor plates between the first and second portions, the one or more sensors configured to measure forces transferred from the loading plate to the mounting plate through the one or more sensor plates.

In some examples, a first sensor of the one or more sensors is arranged on an upper portion of a first sensor plate of the one or more sensor plates, and a second sensor of the one or more sensors is arranged on a lower portion of the first sensor plate.

In disclosed examples, a lift truck weighing device comprising a carriage mounted scale configured to support one or more load handling fixtures and to be secured to a lift truck carriage that includes one or more rails secured to the lift truck carriage; and one or more sensors arranged at a mounting interface between the lift truck carriage and the carriage mounted scale, the one or more sensors configured to measure a load from the one or more load handling fixtures.

In some examples, one or more mounting blocks with the one or more sensors incorporated therein, the one or more mounting blocks configured to secure the lift truck carriage to the carriage mounted scale.

In some examples, the one or more sensors are incorporated in the carriage mounted scale and arranged between a load handing fixture mount and a mounting fastener between the lift truck carriage and the carriage mounted scale.

In some examples, the lift truck carriage includes one or more holes to accept at least part of the one or more sensors or a mounting fastener in the lift truck carriage as the one or more sensors extend from the lift truck scale.

Accordingly, the disclosed examples provide a lift truck weighing system provides a versatile system, with increased lift capacity and reduced cost for advanced lift truck attachments. The arrangement of sensors can be modified, as well as provision of measurements to a computing platform, to capture load data for processing, such as compensation and filtering, to improve measurement accuracy.

When introducing elements of various embodiments described below, the articles "a," "an," and "the" are intended to mean that there are one or more of the elements. Moreover, while the term "exemplary" may be used herein in connection to certain examples of aspects or embodiments of the presently disclosed subject matter, it will be appreciated that these examples are illustrative in nature and that the term "exemplary" is not used herein to denote any preference or requirement with respect to a disclosed aspect or embodiment. Additionally, it should be understood that references to "one embodiment," "an embodiment," "some embodiments," and the like are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the disclosed features.

As used herein, the terms "coupled," "coupled to," and "coupled with," each mean a structural and/or electrical connection, whether attached, affixed, connected, joined, fastened, linked, and/or otherwise secured. As used herein, the term "attach" means to affix, couple, connect, join, fasten, link, and/or otherwise secure. As used herein, the term "connect" means to attach, affix, couple, join, fasten, link, and/or otherwise secure.

As used herein, the terms "first" and "second" may be used to enumerate different components or elements of the same type, and do not necessarily imply any particular order.

As used herein the terms "circuits" and "circuitry" refer to any analog and/or digital components, power and/or control elements, such as a microprocessor, digital signal processor (DSP), software, and the like, discrete and/or integrated components, or portions and/or combinations thereof, including physical electronic components (i.e., hardware) and any software and/or firmware ("code") which may configure the hardware, be executed by the hardware, and or otherwise be associated with the hardware. As utilized herein, circuitry is "operable" and/or "configured" to perform a function whenever the circuitry comprises the necessary hardware and/or code (if any is necessary) to perform the function, regardless of whether performance of the function is disabled or enabled (e.g., by a user-configurable setting, factory trim, etc.).

The terms "control circuit," "control circuitry," and/or "controller," as used herein, may include digital and/or analog circuitry, discrete and/or integrated circuitry, microprocessors, digital signal processors (DSPs), and/or other logic circuitry, and/or associated software, hardware, and/or firmware. Control circuits or control circuitry may be located on one or more circuit boards that form part or all of a controller.

In the drawings, similar features are denoted by the same reference signs throughout.

<FIG> illustrates an example lift truck attachment system <NUM>, in accordance with aspects of this disclosure. For example, masts <NUM> are supported by a lift truck (not shown), which allow a lift truck carriage <NUM> to move via a mechanical lift in response to a user command. As disclosed herein, a lift truck scale <NUM> is mounted to, or part of, the lift truck carriage <NUM>, and configured to support one or more forks or load handling fixtures <NUM>. Thus, an operator can command the lift truck attachment system <NUM> to raise and/or lower to manipulate a load.

In some examples, the lift truck carriage <NUM> includes support brackets <NUM> that fit within a channel <NUM> of the masts <NUM>. In some examples, the support brackets <NUM> are mounted flush against the masts <NUM>, with or without a channel, and are controlled to rise and/or lower in response to a mechanical force (e.g., from a connected chain, hydraulic, etc.). One or more cross members may be arranged between the support brackets <NUM> to support the lift truck scale <NUM> and/or a forklift attachment <NUM>.

As shown in the example of <FIG> and <FIG>, the one or more cross members can include a first rail <NUM> (e.g., an upper carriage support) and/or a second rail <NUM> (e.g., a lower carriage support). In <FIG>, the first and second rails <NUM> and <NUM> are attachment bearing cross-members mounted to the lift truck carriage <NUM> such that they extend beyond a front edge of the lift truck masts. In some examples, such as in <FIG>, the lift truck carriage <NUM> is configured to nest within the dimensions of the masts <NUM>, such that support brackets <NUM> and/or first and second rails <NUM>, <NUM> do not extend beyond a front edge of the masts <NUM>. In some examples, such as shown in <FIG>, the first and second rails <NUM> and <NUM> are integrated with a forklift attachment <NUM>.

In the example of <FIG>, the first and second rails <NUM>, <NUM> provide a fixture mount <NUM> and/or mounting mechanisms to accept and/or secure either the lift truck scale <NUM> or attachment <NUM>. In some examples, the lift truck scale <NUM> and/or attachment <NUM> includes a mounting block <NUM>, which may be configured to rest on or be secured to the forklift carriage <NUM>, thereby supporting the weight of the lift truck scale <NUM>, attachment <NUM>, and/or forks <NUM>. In examples, the mounting block <NUM> can function as a simply supported beam on the first rail <NUM>, facilitating easy installation and removal, as well as added stability during use. As shown, mounting block <NUM> can include notches and/or other features to ensure the mounting block <NUM> mates with the first rail <NUM>. In some examples, other methods or mechanism can be employed to secure the lift truck scale <NUM> to the lift truck carriage <NUM>, such as bolts, pins, and/or welding.

As disclosed herein, the lift truck scale <NUM> can include a mounting plate <NUM>, such as a plate configured to support a loading plate <NUM> (see, e.g., <FIG>). The loading plate <NUM> can be secured to the mounting plate <NUM> by one or more fasteners <NUM>, a weld, or other suitable technique. When assembled, forks <NUM> are supported by mating hook/attachment <NUM> with a top ridge of the loading plate <NUM>. The lift truck scale <NUM> is configured to mount to the one or more rails <NUM>, <NUM>, which serve to lift a load as well as measure the weight thereof.

Additionally or alternatively, the carriage support between the support brackets <NUM> can be a one or more cross members or a plate configured to directly receive the lift truck scale <NUM>, the loading plate <NUM>, the-attachment <NUM>, or the loading fixtures <NUM>.

Although illustrated as having mating ridges/hooks, the rails, lift truck scales, loading plates, mounting plates, and/or attachments may be configured with additional or alternative mounting features, such as bolts and/or pins, such that the lift truck scale <NUM>, attachment <NUM> and/or loading fixture <NUM> is mounted directly to a carriage support.

As shown in <FIG> and <FIG>, the loading fixture <NUM> and/or attachment <NUM> are configured to mount onto the first rail <NUM> via one or more mounting blocks <NUM>, which generates a generally vertical force downward onto fixture mount <NUM>, as shown in detail in <FIG>. Additionally, the lower portion of the loading fixture <NUM> and/or attachment <NUM> pivots toward the second rail <NUM>, generating a generally lateral force against the fixture mount <NUM> of the second rail <NUM>. As shown in <FIG>, fixture mounts <NUM> are secured to a base portion <NUM> of the rails, which houses one or more load sensors <NUM>. As the loading fixture <NUM> and/or attachment <NUM> exerts a force on the fixture mounts <NUM>, the force is transferred through the base portion <NUM> such that the weight of a load supported by the forks <NUM> is sensed by the one or more load cells <NUM>.

Although examples are provided with each rail having two load cells <NUM>, any number of load cells may be employed, such as a three or more load cells, or a single load cell. Further, in some examples the two rails <NUM> and <NUM> operate in concert (e.g., the respective sensors are employed simultaneously), such that measurements from each sensor or complementary sensors (e.g., from sensors on each rail, from vertically aligned sensors, and/or any combination of sensors), may be provided to a processor to calculate an accurate load weight and/or a component of the load. In addition to or in the alternative, various other parameters or features may be measured, calculated, or otherwise determined via the sensors, such as, for example, strain, end force, side force, vertical force, acceleration, angle, roll and pitch, direction of travel, torque, thrust, as a list of non-limiting examples. In some examples, a single sensor may be employed to weigh the load, and/or one or more sensors may provide a measurement at varying times and/or based on one or more triggers (e.g., a change in position, location, angle, height, etc.).

Although some examples are provided with two rails being employed, in other examples a single rail may be employed, and in yet other examples three or more rails may be employed to measure forces from a load.

Additionally or alternatively, a void or spacing <NUM> may be arranged at an interface between the fixture mount <NUM> and the base portion <NUM>. The void <NUM> aligns generally with the location of the sensors <NUM>. This arrangement serves to focus the forces onto the rails through a central portion <NUM> of the interface.

In some examples, the one or more load cells <NUM> are configured to measure a shear force transmitted through the base portion <NUM> and the sensors <NUM>. Devices and/or components (not shown) may be connected to provide signals corresponding to the output from the load cell(s) <NUM> for analysis, display, and/or recordation, for instance.

For example, information regarding the sensed load is provided to a computing platform for analysis, display, recordation, etc. For example, a processor can be configured to receive and translate information from the one or more load cells <NUM> into a digital format, for display to an operator, to store in memory, and/or transmission to another computing platform, such as a central repository. In some examples, the lift truck scale <NUM> may include a computing platform, to perform all or part of these processing functions. In some examples, the lift truck scale <NUM> may include a wired and/or wireless transceiver to transmit information to another device for processing.

In examples, the load sensor <NUM> is a strain gauge, but can be additionally or alternatively a piezoelectric crystal, a displacement transducer, accelerometers, inclinometers and/or tilt sensors, vibrating beam sensors, fiber optic sensors, or some other type of sensor that provides desired sensitivity and accuracy. An example one or more load sensors <NUM> may include an impedance or resonator, such as a quartz crystal. Such sensors <NUM> are excited by DC, pulsed or switched polarity.

Strain gauge load cells operate under principles where deformation provides a voltage output proportional to the deformation based on the material characteristics.

A processor that receives the output is capable of resolving and measuring reactive forces acting on force sensor(s) <NUM>.

For example, the force sensor(s) <NUM> are configured to generate a signal representative of the force applied during a measuring operation and transmit that signal to a device configured to receive and analyze the signal. The electrical signal output is then measured by the device and the amplitude of the load calculated as a result, where this force is translated into a signal that is sent to a circuit for evaluation.

For example, the force sensor(s) <NUM> may be in communication with a processor and/or other device to generate an output associated with a measured value (e.g., for display, to provide an audible alert, for transmission to a remote computing platform, for storage in a medium, etc.). The processor is configured to parse analog or digital signals from the one or more sensors in order to generate the signal. Generally, any number or variety of processing tools may be used, including hard electrical wiring, electrical circuitry, transistor circuitry, including semiconductors and the like.

The processor may be associated with a memory circuit which may consist of one or more types of permanent and temporary data storage, such as for providing the analysis on force sensor data and/or calibration. In some examples, a calibration process may be performed.

The memory can be configured to store calibration parameters for a variety of parameters, such as load cell type, force sensor type, etc. The historical measurement data can correspond to, for example, operational parameters, sensor data, a user input, as well as data related to trend analysis, threshold tension values, profiles associated with a particular measurement process and/or cable type, etc., and can be stored in a comparison chart, list, library, etc., accessible to the processor. The output from the processor can be displayed graphically, such as the current load measurement, a historical comparison, or desired load value, for instance.

<FIG> illustrates a perspective view of another example lift truck weighing system. In the example of <FIG>, an example lift truck scale 102A includes a loading plate <NUM> secured to a mounting plate <NUM> via one or more fasteners <NUM> and/or by other securing methods and/or mechanisms, such as welding. For example, the fasteners <NUM> can be used to mount the plate <NUM> to plate <NUM> via from a variety of angles or directions. Some arrangements of fasteners <NUM> may provide flexibility and/or space for wiring, electronics, centering pins, information or identification plates, for instance.

In the example of <FIG>, an opening or channel <NUM> is arranged between vertically paired fasteners <NUM>. In some examples, the opening <NUM> is arranged between horizontally paired fasteners. Although illustrated as two openings at opposing ends of the lift truck scale 102A (e.g., aligned with mounting brackets <NUM>), a single opening may be employed, or more than three openings may be employed.

One or more sensors <NUM> are located within one or more of the openings <NUM>. For example, one or more support elements may secure a sensor within the opening <NUM>, such that forces transmitted through the lift truck scale 102A are measured by the sensor(s) <NUM>. The sensor(s) <NUM> may measure a load and/or transmit such measurements as disclosed herein.

In examples, each opening is substantially identical. In some examples, one or more of the openings have a different depth or a different width. In some examples, one or more of the openings are filled with a material having different characteristics than a material used to form the plate or structure housing the sensor.

Although the opening and sensor are illustrated as arranged within the loading plate <NUM> in <FIG>, in some examples (e.g., shown in <FIG>) a single plate may be used (e.g., either of a mounting plate or loading plate), or another type of load fixture mounting arrangement or device, such that the opening and sensor may be provided in a single plate or alternative mounting device.

<FIG> illustrates a perspective rear view of the example lift truck scale 102A provided in <FIG>. As shown, the attachment <NUM> is designed to extend into the space between the masts <NUM>, thereby limiting the distance between the front edge of the masts <NUM> and the base <NUM>. Such an arrangement provides a lower profile for the lift truck attachment system <NUM> versus conventional designs, where support mounts extend beyond the front edge of the masts. As shown in the disclosed examples, the load bearing portion of the carriage supports <NUM>, <NUM> are substantially located between the masts <NUM>. For example, the attachment <NUM> interfaces directly with upper carriage support <NUM>, such that device mounting cross-members on the surface of the masts <NUM> are avoided.

<FIG> and <FIG> provide perspective views of an example lift truck weighing system with an example sensor plate <NUM> for use in a lift truck scale, in accordance with aspects of this disclosure. For example, the sensor plate <NUM> includes a first or top portion <NUM>, a second or central portion <NUM>, and a third or lower portion <NUM>. The various portions are separated by one or more voids 152A, 152B, which are configured to house one or more sensors <NUM>.

In some examples, the first portion <NUM> and the third portion <NUM> are secured to a first mounting surface (e.g., of a mounting plate) via one or more fasteners 115A, and the second portion <NUM> is secured to a second mounting surface (e.g., of a loading plate) via one or more fasteners 115B. As shown in the example of <FIG>, the sensors <NUM> and the voids housing them are arranged at an interface between mounting arrangements, such that any forces traveling from one mounting surface to a second mounting surface impacts the sensors <NUM>.

As disclosed herein, a loading plate may receive fixturing which supports a load. Forces from the weight of the load travel through the loading plate, then through the sensor plate <NUM>, and into the mounting plate. As the forces traverse the voids 152A and/or 152B, the sensors <NUM> arranged therein measure the forces, such measurements can then be provided to another device for processing, in accordance with aspects of this disclosure.

One or more of the voids 152A and/or 152B may be enclosed by portions of the sensor plate <NUM> (such as the illustrated void 152A), and/or have one or more sides exposed (such as the illustrated void 152B). Further, although illustrated as oriented substantially vertically, the sensor plate <NUM> may be oriented at any angle, such as substantially horizontally.

Returning to <FIG>, the sensor plate <NUM> is secured to a mounting plate <NUM> (e.g., a first mounting surface) and configured to be secured to a loading plate <NUM> (e.g., a second mounting surface). As shown, a pair of sensor plates <NUM> are aligned with the mounting brackets <NUM> and secured to the mounting plate <NUM> at the first or top portion <NUM> and the third or lower portion <NUM> via one or more fasteners 115A and 115B, as shown in <FIG>.

<FIG> illustrates a perspective view of another example lift truck weighing system with the sensor plate <NUM> secured to a loading plate <NUM> (e.g., a second mounting surface) but without a mounting plate <NUM>. Instead, the sensors plate <NUM> is directly attached to either the forklift carriage <NUM> or an attachment <NUM>.

<FIG> illustrate example lift truck weighing systems, such that a sensor <NUM> is arranged at a mounting interface between a forklift carriage <NUM> and loading fixture <NUM> (and/or another support bracket fixed to a mast).

In the example of <FIG>, one or more openings or holes <NUM> are provided in the rails <NUM>, <NUM>, and are configured to accept a fastener <NUM> with an incorporated sensor <NUM>. Thus, when mounted to the rails <NUM>, <NUM>, any force traveling from the lift truck scale <NUM> to the rails <NUM>, <NUM> will pass through the sensors <NUM>.

In the example of <FIG> and <FIG>, sensors <NUM> are arranged within the lift truck scale <NUM> between the top portion <NUM> (to support load fixturing) and a bottom portion <NUM>. A central portion <NUM> includes one or more mounting brackets <NUM> mounted thereto (e.g., via fasteners, welding, pins, etc.), which interface with the rails <NUM>, <NUM> to secure the lift truck scale <NUM>. Thus, any force traveling from the lift truck scale <NUM> to the rails <NUM>, <NUM> will pass through the sensors <NUM>.

The lift truck scale <NUM> is configured to support a load handling fixture. As shown in <FIG>, the lift truck scale <NUM> is then secured to the rails <NUM>, <NUM> via mounting brackets <NUM>. One or more sensors <NUM> are incorporated within one or more of the mounting brackets <NUM>, such that any force traveling from the lift truck scale <NUM> to the rails <NUM>, <NUM> will pass through the sensors <NUM>, which can provide measurements to a computing platform for processing, as disclosed herein.

Additionally or alternatively, the arrangement or orientation of the rails can be reversed, such that the rail <NUM> becomes load bearing, for example, as shown in <FIG>. In some examples, a retaining device can be mounted to the lift truck scale <NUM> and/or one of the rails <NUM>, <NUM>, to prevent the lift truck scale <NUM> from inadvertently dislodging from the lift truck carriage <NUM>.

In some examples, one or more of the attachment features (the lift truck scale, mounting plate, loading plate, rails, mounting brackets, loading fixtures, fasteners, etc.) include a preloaded connection (such as a spring, bolt, pin, etc.) to absorb shock and/or to bias the mating surfaces toward one another, resulting in a force to maintain constant contact. In some examples, a shape of the mating surface can be modified to achieve a desired performance result. Such modifications can include a cast ball-shaped interface, mating V-shaped contacts, grooves, ridges, etc..

Claim 1:
A lift truck carriage (<NUM>) comprising one or more rails (<NUM>, <NUM>), each rail comprising a fixture mount (<NUM>) to support one or more load handling fixtures (<NUM>) and
characterised in that
a base portion (<NUM>) to house a sensor (<NUM>) configured to measure forces on the one or more rails (<NUM><NUM>) from the one or more load handling fixtures (<NUM>).