Classifications

• • E—FIXED CONSTRUCTIONS
  • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
  • E02F—DREDGING; SOIL-SHIFTING
  • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
  • E02F9/26—Indicating devices
  • E02F9/264—Sensors and their calibration for indicating the position of the work tool
• • E—FIXED CONSTRUCTIONS
  • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
  • E02F—DREDGING; SOIL-SHIFTING
  • E02F3/00—Dredgers; Soil-shifting machines
  • E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
  • E02F3/28—Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets
  • E02F3/36—Component parts
  • E02F3/3604—Devices to connect tools to arms, booms or the like
  • E02F3/3609—Devices to connect tools to arms, booms or the like of the quick acting type, e.g. controlled from the operator seat
  • E02F3/3618—Devices to connect tools to arms, booms or the like of the quick acting type, e.g. controlled from the operator seat with two separating hooks
• • E—FIXED CONSTRUCTIONS
  • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
  • E02F—DREDGING; SOIL-SHIFTING
  • E02F3/00—Dredgers; Soil-shifting machines
  • E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
  • E02F3/28—Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets
  • E02F3/36—Component parts
  • E02F3/3604—Devices to connect tools to arms, booms or the like
  • E02F3/3609—Devices to connect tools to arms, booms or the like of the quick acting type, e.g. controlled from the operator seat
  • E02F3/3622—Devices to connect tools to arms, booms or the like of the quick acting type, e.g. controlled from the operator seat with a hook and a locking element acting on a pin
• • E—FIXED CONSTRUCTIONS
  • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
  • E02F—DREDGING; SOIL-SHIFTING
  • E02F3/00—Dredgers; Soil-shifting machines
  • E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
  • E02F3/28—Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets
  • E02F3/36—Component parts
  • E02F3/3604—Devices to connect tools to arms, booms or the like
  • E02F3/3609—Devices to connect tools to arms, booms or the like of the quick acting type, e.g. controlled from the operator seat
  • E02F3/3663—Devices to connect tools to arms, booms or the like of the quick acting type, e.g. controlled from the operator seat hydraulically-operated

Definitions

• the present invention relates to improvements in and relating to couplers, in particular to couplers for attaching an implement to a machine.
• Couplers are commonly used for releasably attaching various implements to a machine.
• An example of such a machine is an excavator.
• the couplers used by excavators commonly include at least one, or often two jaws.
• the jaw(s) each engage a pin on an implement to secure the implement to the coupler.
• the couplers are often remotely operable to release and engage an implement. The main reason for this is for ease of use. However, it may also be due to the fact that the implement to be attached is often large and/or heavy and is therefore impossible to move manually, or alternatively is likely to injure personnel attempting to manually attach the implement to the machine.
• Some couplers include a sensor that determines whether a pin is secured in a jaw of the coupler.
• An example of this type of coupler is described in GB2009/002602.
• the type of coupler described in GB2009/002602 can result in an unsafe situation.
• This situation arises when the sensor detects the presence of an implement pin within the moveable jaw, yet the implement is not properly secured.
• One example of when this situation may arise is if the actuator associated with the moveable jaw is faulty.
• the coupler When the coupler is oriented to a position in which the faulty actuator is bearing the weight of the implement, by way of a pin in the movable jaw, the actuator may move under the weight of the implement from a locked position to a position in which the implement is not secured. The operator still sees a locked status from the sensor and, unaware of this situation, may then operate the unsecured implement in a manner which risks damage, injury or death.
• Some couplers that include sensors in one of the jaws may detect a worn pin as being locked in the jaw(s) of the coupler, yet the pin maybe worn to a degree whereby the actuator cannot move the jaw sufficiently far to fully engage the pin. In use, and under load, it may therefore be possible for the implement to pull free from the coupler due to insufficient overlap between the pins and the jaws.
• the present invention relates to a method and apparatus for engaging an implement with a coupling device and indicating a secure state to an operator of the coupler without the need for latching the implement in place.
• the present invention is particularly useful in respect of couplers that are used to couple implements to a back hoe, or excavator.
• the method and apparatus should not be seen as being limited to use solely with such machines.
• a coupler for attaching an implement to a machine including:
• the first jaw is a fixed jaw.
• the fixed jaw is attached to or formed integrally with the body portion.
• An integral attachment could be one in which the fixed jaw is formed from the same piece of material as the body portion, or alternatively the fixed jaw could be attached in a way in which the fixed jaw and body portion are fixed together, examples of such attachment may include welding, bolting, riveting or the like.
• the coupler may be configured to attach to an articulated arm.
• the articulated arm is a back hoe.
• the fixed jaw is substantially 'U' shaped, the opening of the 'U' facing in an outward direction substantially parallel to the length of the body portion.
• the fixed jaw is configured to engage with a first attachment portion in the form of a pin.
• the moveable jaw is moveable between: • an engaging position in which it engages the second engagement portion; and
• the moveable jaw is slidably coupled to the body portion so that the moveable jaw moves in a sliding motion between the engaged position and the non- engaging position.
• the moveable jaw may also be rotatable or pivotal between the engaged position and the non-engaging position.
• the movable jaw includes a substantially 'U' shaped engaging portion configured to engage with the second attachment portion.
• the opening of the 'IT facing in an opposite direction to the fixed jaw when in the engaging position.
• the coupler of the present application is for use with an implement that includes an attachment in the form of two spaced apart parallel pins or the like.
• the spacing between the jaws in the non-engaging position is such that when a first pin of the implement is positioned in the U shaped fixed jaw the implement can be rotated to position the second pin opposite the U shaped opening of the moveable jaw. Moving the moveable jaw to the engaging portion increases the spacing between the fixed and movable jaws and locks the moveable jaw in the coupler.
• the first sensor is located adjacent the moveable jaw.
• the first sensor is positioned so as to be abutted by a portion of the implement when, in use, the implement is positioned such that the second attachment portion is engageable by the moveable jaw.
• the implement is rotated to position the second pin opposite the moveable jaw the second attachment portion, or part of the implement, abuts the coupler.
• the weight of the implement presses on the sensor to indicate the second attachment portion is in a safe position, i.e. the first attachment portion of the implement is secured in the fixed jaw and cannot, for example, bounce free.
• the first sensor is positioned so as to abut the second attachment portion of the implement, or part thereof.
• the first sensor may be positioned in a number of locations along the length of the body portion, provided it is capable of either directly or indirectly detecting when the second attachment portion is opposite to and engageable by the moveable jaw.
• the first attachment portion is hooked/engaged by the first/fixed jaw of the coupler.
• the coupler is then rotated, causing the second attachment portion to swing towards the coupler.
• the operator can activate the moveable jaw to lock the implement in place.
• the implement only requires moving, or lifting, onto a transport vehicle the operator does not necessarily need to activate the moveable jaw.
• the functionality of the machine may be limited when the moveable jaw is not engaged with the second attachment portion of the implement, for example the maximum speed, angle on which the machine will operate, rate of movement of one or more components, or height to which the implement can be lifted may be limited.
• sensing of the implement as being adjacent to the body portion at a location spaced apart from the fixed jaw indicates the angular position of the coupler relative to the implement.
• the coupler may include a second sensor configured to detect whether the movable jaw is in the engaging position, or non-engaging position.
• the second sensor may take a number of forms. However it will typically take the form of a sensor configured to measure the state of an actuator associated with movement of the moveable jaw.
• the coupler may include a third sensor configured to detect the presence of the first attachment portion within the fixed jaw.
• the second sensor may sense the position of a component associated with the moveable jaw.
• the actuator is a hydraulic cylinder and the second sensor is configured to measure the expansion and/or degree of contraction of the actuator.
• the first sensor is used in combination with the second sensor and/or third sensor to indicate whether the implement is securely retained by the coupler. It will be appreciated by a person skilled in the art that for the implement to be securely retained the implement first attachment portion must be retained in the first jaw, the implement must be adjacent to the body portion of the coupler and the moveable jaw must be in the engaging position.
• the third sensor indicates that the first attachment portion has been hooked by the fixed jaw; this indicates to the operator that the coupling can be safely rotated.
• the first sensor indicates when the second attachment is positioned opposite the moveable jaw, this indicates that the first attachment portion is safely secured in the fixed jaw and also indicates that the implement can be locked into position by moving the moveable jaw to the engaging position.
• the second sensor indicates that the movable jaw is in the engaging position.
• a system for coupling an implement to a machine including:
• a coupler having a body portion including a fixed jaw attached to the body portion and configured to engage a first attachment portion associated with the implement; a moveable jaw moveably attached to the body portion and configured to engage a second attachment portion associated with the implement;
• an attachment between the coupler and the machine configured to impart a rotation to the coupler about a pivot axis parallel to a width of the fixed jaw, wherein, in use, rotation of the coupler about the pivot axis allows the body portion of the coupler to be rotated relative to the implement first attachment portion, and
• system for coupling may include a second sensor configured to detect the position of the movable jaw.
• measurement of the position of the movable jaw may be made directly, or indirectly.
• Direct measurement may involve, for example measuring the physical position of the jaw.
• Indirect measurement may involve sensing the position of a component associated with the moveable jaw. In such alternatives the position of the component being measured is directly relatable to the position of the moveable jaw.
• the second sensor configured to detect the position of the movable jaw senses whether the movable jaw is in an engaging position, or a non-engaging position.
• system may include a third sensor configured to detect the presence of the first attachment portion within the fixed jaw.
• the system includes an indicator unit.
• the indicator unit provides an indication to an operator of the system when the presence of the implement is detected as being adjacent to the body portion.
• the indicator unit includes an electronic indicator; examples of electronic indicators may include, but should not be limited to, visible lights such as LEDs, alarms, buzzers or tactile feedback or the like.
• the indicator unit is located remotely to the coupler.
• system may be integrated with, or coupled to, a control system associated with a machine to which the coupler is attached.
• control system associated with the machine to which the coupler is attached may limit one or more functions of the machine if, in use, the implement is not sensed as being adjacent to the body portion.
• appropriate features that may be limited are, hydraulic power, a reduced range of motion, a reduced rate of movement, or similar.
• a method of coupling an implement to a machine using a coupler having a body portion including a fixed jaw attached to the body portion and configured to engage a first attachment portion associated with the implement; a moveable jaw moveably attached to the body portion and configured to engage a second attachment portion associated with the implement, and a first sensor located on the body portion configured to detect the presence of the implement adjacent to the body portion and at a location spaced apart from the fixed jaw, the method including the steps of: a) engaging the implement first attachment portion with the fixed jaw; b) rotating the coupler about a pivot axis parallel to a width of the fixed jaw so as to move the underside of the body portion towards the implement; c) detecting, by way of the first sensor, whether the second attachment portion of the
• step d) In use, the outputting of a signal of step d) indicates the implement is in a position whereby the implement can be locked into position by the moveable jaw.
• a sensor configured to be used with a coupler for attaching an implement to a machine, the sensor including
• an insulating portion formed from a resilient electrically insulating material, the insulating portion having a base on one side and a receiving surface on the opposite side;
• a conductive member configured to be retained on the receiving surface, wherein the conductive member is electrically isolated from the base of the insulating portion.
• the senor operates in conjunction with the chassis of the machine to which the coupler is attached.
• the machine, coupler body, and implement to be attached form an electrically conductive path through which a current can flow.
• current passes through the machine, into the coupler and through the implement via the first attachment; which is held in the fixed jaw.
• the implement forms a mechanical switch which is closed, i.e. conducts current, when a portion of the implement abuts the conductive member of the sensor.
• a closed circuit is not formed and no current flows.
• an insulated return wire is provided from the conductive member to a detection circuit.
• the conductive member is configured to be electrically coupled to an electrical signal detector.
• the conductive member is configured to project outwards from the receiving surface of the insulating portion.
• the base is configured to be attached to a surface of the coupler.
• the insulating portion is elongate.
• the conductive member is elongate.
• the conductive member is configured, in use, to abut a portion of an implement when a second attachment portion of the coupler is in a position in which it can be engaged by a moveable jaw of the coupler.
• the senor is configured to be compressed between a portion of the implement and a portion of the coupler body.
• Preferred embodiments of the present invention may provide a number of advantages over the prior art, examples of which may include:
• moveable jaw of a coupler will engage the moveable jaw with the implement, thereby securing the implement to the coupler; • providing a warning to an operator when an implement is no longer securely held in a secure position, for example in the event whereby the actuator fails and disengages the moveable jaw;
• Figure 1 a shows a plan view of a coupler in accordance with one preferred embodiment of the present invention
• Figure 1 b shows a plan view of the coupler of Figure 1 in an engaged position
• Figure 2 shows a cross sectional view of the coupler of Figure 1.
• Figure 3a shows a perspective view of a sensor in accordance with one preferred
• Figure 3b shows an exploded view of the sensor of Figure 2a
• Figure 4 shows a plan view of the coupler of Figure 1 and an attached implement in an unsecure position
• Figure 5 shows a plan view of the coupler of Figure 1 and an attached implement in a secure position
• Figure 6 shows a plan view of the coupler of Figure 1 and an attached implement in an engaged position
• Figure 7a - 7c show schematic views of a system for coupling an implement to a
• Coupler 1 includes a body portion 2 to which is attached a fixed jaw 3.
• the jaw 3 is fixed in the sense that it does not move with respect to the body portion 2.
• fixed jaw 3 may take a number of forms without departing from the scope of the present invention.
• fixed jaw 3 may be formed integrally with the body portion of coupler 2, or it may be attached to the body portion 2 by way of bolts or other suitable fasteners.
• Fixed jaw 3 includes a 'IT shaped opening 3a facing in an outward direction substantially parallel to the length of the body portion.
• the 'IT shaped opening is configured to receive the circular cross section of a first attachment pin 12a (shown in figure 2) of an implement (shown in figures 4, 5 and 6) the first pin 12a extends across the width of the fixed jaw 3 so as to be substantially transverse to the length of body portion 2.
• a moveable jaw 4 is moveably attached to the body portion 2.
• the movable jaw 4 includes a substantially 'IT shaped engaging portion 4a, the opening of the 'U' facing in an opposite direction to the 'IT shape of the fixed jaw 3.
• the 'U' shaped engaging portion 4a is configured to receive a second attachment pin 12b (shown in Figure 2), which, in use, extends across the width of the movable jaw 4.
• a second sensor 40 detects the position of movable jaw 4 by measuring the position of the shaft of hydraulic ram 41 (shown in Figure 2), and a third sensor 14 detects the presence of first pin 12a in fixed jaw 3.
• the moveable jaw 4 is configured to slide along a portion of the length 4b of the coupler body portion 2 towards and away from fixed jaw 3. In use, movement of the moveable jaw 4 alters the spacing between the fixed jaw 3 and the moveable jaw 4, this movement facilitates the clamping, or engagement of an implement with the coupler 1. It should be appreciated that alternatives to sliding movement of the moveable jaw 4 may be considered, for example, the movable jaw may rotate rather than slide. The manner in which the fixed jaw and moving jaw provide clamping of an implement is explained in greater detail later in this document with respect to Figures 2 to 5.
• the moveable jaw 4 is moveable between an engaging portion, shown in figure 1 a wherein the moveable jaw is positioned relatively closer to the fixed jaw 3 and a non-engaging position, shown in Figure 1 b, wherein the moveable jaw 4 is positioned relatively further from the fixed jaw 3.
• the coupler 1 also includes a first sensor 5 located on the body portion 2, the first sensor 5 is positioned adjacent to the moveable jaw 4.
• the first sensor 5 includes an insulating portion 6 formed from a resilient electrically insulating material.
• the insulating portion 6 has a base 7 on one side and a receiving surface 8 on the opposite side.
• a cable 10 is sandwiched between conductive member 9 and the receiving surface 8 to which the conductive member 9 is attached.
• the insulating portion 6 base 7 is, in use, attached to the coupler body 2. Because the conductive member 9 is insulated by the insulating portion 6 there is no electrical connection between the coupler body and the conductive member 9. In use the conductive member 9 is configured to abut a portion of an implement.
• the first sensor 5 will be elongate, so as to cater for a range of differently spaced first and second attachment pins.
• the insulating portion 6 compresses when an implement presses against the conductive member 9, this allows contact to be made between the implement and the conductive member 9 whilst allowing the implement to bear against the body portion 2.
• Coupler 1 is configured to attach to a machine by way of connection points 11a and 11 b.
• connection points 11a and 11b allow for rotation of the coupler about an axis substantially parallel to the width of the fixed jaw 3.
• Excavator bucket 12 includes a first attachment portion in the form of pin 12a and a second attachment portion, spaced apart from the first attachment portion, in the form of pin 12b.
• Figure 2 shows the implement 12 first attachment portion pin 12a engaged within fixed jaw 3.
• Figure 4 shows the coupler of figure 2 in a position in which the coupler 1 has been rotated about a pivot axis parallel to a width of the fixed jaw 3. Rotation is facilitated by an attachment (not shown) between the coupler 1 and the machine (not shown). Rotation of the coupler 1 rotates the body portion 2 relative to the first attachment portion pin 12a, thereby moving the moveable jaw 4 towards the second attachment portion 12b. It will be appreciated that, in use, the implement will typically hang from the fixed jaw 3 by way of the first attachment portion pin 12a. The hanging orientation of the implement will therefore be dictated by its centre of mass relative to the first attachment portion pin 12a.
• Rotation of the coupler 1 results in the excavator bucket 12 second attachment portion 12b pressing against the first sensor 5 conductive member 9 compressing insulating portion 6. Compression of the insulating portion 6 allows the second attachment portion 12b to bear against the coupler body portion 2 whilst completing an electrical circuit through the coupler fixed jaw 3, the first attachment portion 12a, the excavator bucket 12, the second attachment portion 12b, the conductive member 9 and cable 10.
• Completion of the electrical circuit is indicative of the position of pin (12b) with respect to the body portion (2). Therefore, it is possible to determine whether the coupler (1) is in a position in which movable jaw (4) can engage pin (12b).
• Completion of the circuit results in an indication to a user that the implement second attachment portion pin 12b is in a position in which the movable jaw 4 can be moved from a non-engaging position (shown in Figure 4), wherein the second engagement portion 12b is able to move freely relative to the body portion 2, to an engaging position (shown in Figure 5), wherein the second engagement portion 12b is engaged by, and held substantially fixed relative to, the body portion 2 by the moveable jaw 4.
• coupler 30 of the type shown in figures 1 to 2
• coupler 30 includes a third sensor 31 which is provided for association with the fixed jaw and is positioned so as to detect the presence of the first attachment portion 12a within the fixed jaw.
• a first sensor 32 is positioned adjacent the moveable jaw and is configured to detect the presence of the implement when it is adjacent to the body portion of the coupler.
• An indicator unit 33 is located remotely from the coupler 30 and includes a relay switch 36 to toggle between safe indication light source 34 and unsafe indication light source 35.
• the third sensor 31 and first sensor 32 are connected in parallel by way of sense wire 37 and through the chassis 38 of the coupler.
• attachment portion pin 12b is not detected as being adjacent the coupler body, OR b) the first attachment portion pin 12a is located in the fixed jaw and second attachment portion pin 12b is detected as being adjacent the coupler body.
• Variants that include a second sensor for measuring the position of the moveable jaw 4, shown in figure 2, will also require that the moveable jaw is in the engaged position. This is in addition to the requirements detailed in step b) above. Typically such variants would incorporate a second sensor which sits in parallel with the first and third sensors. When the jaw is in a non- engaging position the second sensor 40 completes the circuit through sense wire 37 and thereby indicates an unsafe condition.
• the advantage of monitoring the position of the moveable jaw is that if the actuator, hydraulic ram of figure 2, fails and disengages, or fails to move, the moveable jaw to engage the second work attachment pin 12b the operator is alerted.
• the system may also include a further sensor (not shown) that indicates the position of the movable jaw 4.
• a further sensor (not shown) that indicates the position of the movable jaw 4.
• Numerous alternatives exist by which the jaw position could be measured not limiting examples of which include, measuring the shaft position of a hydraulic cylinder associated with the movable jaw, measuring a hydraulic pressure provided to the movable jaw, or direct measurement of the position of the jaw.
• system may also limit one or more functions of the machine when an implement is not detected as being secure within the fixed jaw, ie when the unsafe indication light source 35 is active.
• Non-limiting examples of limitation of one or more functions of the machine may include, reduced hydraulic power, a reduced range of motion, or a reduced rate of movement.
• the detection of the implement moving away from the body of the coupler may be indicative of a number of unsafe conditions. For example, in the event in which the actuator fails and releases one of the implement pins the implement will swing away from the coupler, at which time the operator will be alerted as to the unsafe operating condition.
• a further example is the situation whereby the implement pins may be worn. Whilst pin detection sensors in the jaws may indicate the presence of the pins in the jaws, indication of the, or a, pin moving away from the coupler body, but still remaining within the jaw, is indicative of pin wear. If a pin is worn to the point whereby it begins to move away from the coupler body during use, the operator will be alerted. Once the pins begin moving in the coupler jaws during use the rate of wear will increase substantially. By alerting the operator early remedial action may be taken early avoiding costly downtime in the event of a pin failure, and also avoiding safety risks

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Mining & Mineral Resources (AREA)
• Civil Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Structural Engineering (AREA)
• Component Parts Of Construction Machinery (AREA)

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• 2014
  • 2014-10-22 WO PCT/NZ2014/000221 patent/WO2015060730A1/en not_active Ceased
  • 2014-10-22 EP EP14855461.1A patent/EP3060724A4/de not_active Withdrawn
  • 2014-10-22 AU AU2014337788A patent/AU2014337788A1/en not_active Abandoned
• 2016
  • 2016-04-22 US US15/136,701 patent/US20160237656A1/en not_active Abandoned

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