Grabbing device

Abstract

A grabbing device having a plurality of jaws which can be moved between an open position and a closed position to enable the device to grasp an object(s). The technology finds particular application in the forestry industry and moving logs.

Claims

1. A grabbing device, including a first body, a flexible length of material having a first end and a second end, and a middle section in between the first end and second end, wherein the first end of the flexible length is fixed or configured to be connected to a hauler, an arrangement configured to urge the middle section of the flexible length to move with respect to the first body, a second body providing an axle, wherein the flexible length extends around the axle and is fixed to the first body at or towards the second end, a first jaw and a second jaw which in use interact with each other so as to engage an object and thereby secure the object with respect to the grabbing device, a brake moveable between: a locking position in which the brake prevents the middle section of the flexible length moving with respect to the first body so as to hold the amount of the flexible length between the first end and the brake constant, and a release position in which the brake allows the middle section of the flexible length to move with respect to the first body so as to allow the amount of the flexible length between the first end and the brake to change.

2. The grabbing device as claimed in claim 1, wherein the flexible length comprises a chain.

3. The grabbing device as claimed in claim 1, wherein the first jaw comprises at least one rigid arm.

4. The grabbing device as claimed in claim 3, wherein the second jaw comprises at least one rigid arm.

5. The grabbing device as claimed in claim 1, including a remote control configured to control operation of the grabbing device.

6. The grabbing device as claimed in claim 5, wherein the remote control is configured to engage or disengage the brake.

7. The grabbing device as claimed in claim 5, wherein the remote control is configured to control operation of an adjustment mechanism.

8. The grabbing device as claimed in claim 1, including an adjustment mechanism.

9. The grabbing device as claimed in claim 8, wherein the adjustment mechanism includes at least one rotating means.

10. The grabbing device as claimed in claim 8, wherein the adjustment mechanism includes at least one tilting means.

11. The grabbing device as claimed in claim 1, including a fastener provided to the first end of the length of material and which is configured to secure the grabbing device to a yarding arrangement.

12. The grabbing device as claimed in claim 1, wherein the brake is a drum brake.

13. The grabbing device as claimed in claim 1, wherein the first jaw and the second jaw are pivotally attached to the first body.

14. The grabbing device as claimed in claim 13, wherein the first jaw and the second jaw are also pivotally mounted with respect to the second body.

15. The grabbing device as claimed in claim 1, wherein the first jaw and the second jaw are configured to move from an engaged position towards an open position as the first body moves away from the second body.

16. The grabbing device as claimed in claim 1, wherein the first jaw and the second jaw are configured to move to a position in which they interact with each other so as to engage an object and thereby secure the object with respect to the grabbing device when the first body moves towards the second body.

17. The grabbing device as claimed in claim 1, wherein the connection of the first end to the hauler enables the hauler to raise and lower the grabbing device.

18. The grabbing device as claimed in claim 1, wherein the first body includes a spring which applies an urging force to a cog to rotate to thereby move the middle section of the flexible length to move with respect to the first body.

19. The grabbing device as claimed in claim 1, wherein the first body and second body are mechanically linked to each other.

20. The grabbing device as claimed in claim 1, wherein the brake is located on the first body.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further aspects of the present invention will become apparent from the ensuing description which is given by way of example only and with reference to the accompanying drawings in which:

(2) FIG. 1 is a first perspective exploded view of an aspect of the present invention;

(3) FIG. 2 is a second perspective view of FIG. 1;

(4) FIG. 3 is a side cross-sectional view of an assembled grabbing device according to one aspect of the present invention in an open position;

(5) FIG. 4 is a side view of FIG. 3;

(6) FIG. 5 is a rear view of FIG. 3;

(7) FIG. 6 is a perspective view of FIG. 5;

(8) FIG. 7 is a side view of a grabbing apparatus in an open position;

(9) FIG. 8 is a sectional view of a grabbing apparatus according to one aspect of the present invention in a closed position;

(10) FIG. 9 is a side view of FIG. 8;

(11) FIG. 10 is a perspective view of FIGS. 8 and 9;

(12) FIG. 11 is a representative view of a yarding arrangement;

(13) FIG. 12 is a first side view of a grabbing apparatus according to an embodiment of the invention in an open position;

(14) FIG. 13 is a view of FIG. 12 showing a grabbing device according to an embodiment of the invention in a closed position

(15) FIG. 14 is a first side cross sectional view of a grabbing apparatus according to an alternate embodiment of the invention in an open position;

(16) FIG. 15 is a second side cross sectional view of the grabbing apparatus according of FIG. 14;

(17) FIG. 16 is a close up view of a section of FIG. 14.

BEST MODES FOR CARRYING OUT THE INVENTION

(18) Referring first to FIG. 3-6 showing a grabbing device generally indicated as (100). The grabbing apparatus (100) includes a first body (200) and a second body (300).

(19) A first jaw (400) is provided to the second body (300) by being rotatably mounted on an axle (310) that is mounted in the second body (300).

(20) A second jaw (500) is provided to the second body (300) by being rotatably mounted on an axle (320) that is mounted in the second body (300).

(21) The second body (300) is formed from a first plate (330) and a second plate (332) as are seen in FIGS. 6 and 8.

(22) The axles (310, 320) in combination with other bolts (not shown) act to immovably secure the first plate (330) and the second plate (332) with respect to each other.

(23) A cog (340) is rotatably mounted on axle (342) that is secured between the first and the second plate (332).

(24) A first linkage arm (410) is pivotally secured to the first jaw (400) using an axle (417). In addition, the linkage arm (410) is pivotally secured to the first body (200) using an axle (416).

(25) A second linkage arm (510) is pivotally secured to the first body (200) using an axle (516). In addition, the second jaw (500) is pivotablly secured to the second body (300) using an axle (517).

(26) Referring now to FIGS. 1 and 2 showing aspects of the first body (200).

(27) The first body (200) is formed from a first plate (202) and a second plate (204). A cog (210) is rotatably mounted between the first plate (202) and the second plate (204) by an axle (212). The axle (212) includes detents (212A, 212B). The detents (212A, 212B) extend in opposite directions, from each other, being positioned on distal sides of the axle (210) from each other.

(28) The detents (212A, 212B) correspond to apertures (214A, 214B) in the cog (210). A spring (216) is mounted to the first body (200) using a mounting plate (220). The mounting plate (220) includes a housing (222) configured to receive the spring (216). An end (218) of spring (216) sits within a notch (not shown in the Figures) in housing (220). Accordingly, the end (218) of spring (216) is prevented from moving relative to the housing (222). However, a second end (219) of the spring (216) is fixed to the bush (230).

(29) The bush (230) is configured to receive and/or rigidly fixed to an end of the axle (212).

(30) A housing closing plate (232) is configured to close the housing (222) so as to secure the spring (216) therein. This may be achieved by screw fasteners (not shown the Figures) which extend through apertures (234) to engage threaded apertures (236) in the housing (222).

(31) A guide (240) is secured in between the first plate (202) and the second plate (204). The guide (240) provides an entrance way into the first body (200).

(32) A first roller (242) and a second roller (244) are each mounted in the first body (200) by axles (246) and (248) respectively. The rollers (242, 244) are positioned so as to be adjacent to the cog (210), but are vertically staggered with respect to the cog (210) when the grabbing device (100) is in its normal orientation in use e.g. roller (242) is above roller (244). The orientation and position of the cog (210) and rollers (242, 244) with respect to each other is best shown in FIG. 3.

(33) A second guide (249) is secured in the first body (200) between the first plate (202) and the second plate (204).

(34) A flexible length in the form of a chain (250) is threaded through the first body (200). The chain (250) has a first end (252) and a second end (254). The second end (254) is fixably secured to the first body (200) in between the first plate (202) and the second plate (204) using techniques as should be understood by one skilled in the art such as by a shackle (not shown).

(35) The chain (250) includes a middle section, being a section of the chain (250) between the first end (252) and the second end (254). The middle section of the chain (250) wraps around the cog (210) and extends through the second guide (254) in between the roller, cog (210), and the first roller (246) and the cog (210) and through the guide (246). Accordingly, the second end (254) is outside of the first body (200) as is shown in FIG. 3.

(36) A brake indicated generally as (700) is provided in the form of a drum brake.

(37) The brake (700) includes a drum housing (710) which is connected to the first plate (302) such as by screws, bolts and/or welding.

(38) The drum housing (710) is configured to receive a drum (712). The drum (712) has a recessed shoulder (718) which is stepped in from an outer edge (714). The recessed shoulder (718) is configured to receive a clamping band (720). The clamping band (720) may be made from spring materials such as steel, stainless steel, and/or other resilient materials.

(39) A drum housing closing plate (724) is provided to close the drum housing (710). This is achieved by fasteners (not shown in the figures) which extend though apertures (726) in the drum housing closing plate (724) to engage threaded apertures (728) in the drum housing. A first end (730) of the clamping band (720) is immovably secured with respect to the drum housing (710).

(40) A second end (738) of the clamping band (720) is able to move within the drum housing (710).

(41) The drum (712) is provided to an axle (212) by being fixedly secured thereto. The axle (212) which extends through the drum housing (710) and housing closing plate (724). The drum (712) is fixed with respect to the axle (212). That is, the drum (712) and the axle (212) rotate at corresponding rates to each other. This is achieved by detents (not visible in the figures) on the axle (212) which are disposed within corresponding apertures within the drum (712).

(42) A link (740) is connected to an end (738) of the clamping band (720). The link (740) is connected to an arm (742). The arm (742) is connected to an actuator (750) indicated generally as (750).

(43) The actuator (750) comprises an electric motor (752) and a screw thread drive mechanism (not shown in the figures). In-use, rotation of the electric motor (752) causes a ram (754) to extend or contract linearly. Movement of the ram (754) is transferred to the end (738) of the clamping band (720) via arm (742) and link (740). Thereby, expansion and/or contraction of the actuator (750) can control the tightness of the clamping band (720) around the drum (712). When the clamping band (720) is tightened, it clamps onto the drum (712) to prevent it rotating. When the clamping band (720) is loosened, it releases the drum (712). Thereby, spring (216) can at least partially rotate axle (212).

(44) Referring now to FIG. 11 showing a yarding arrangement (800) including a grabbing apparatus (100) according to one aspect of the present invention. The yarding arrangement (800) includes a first support indicated by (810) and secondary supports indicated by (820, 822, 824).

(45) The first support (810) is a hauling apparatus in the form of an excavator (811) having a telescopic arm (812).

(46) The excavator (811) may include components to adjust the orientation of the telescopic arm (812).

(47) A drive mechanism is configured to move the telescopic arm (812) with respect to the excavator (811). This is as should be understood by one skilled in the art.

(48) The secondary supports (820, 822, 824) are fixed points such as tree stumps as illustrated. They may also be secondary excavators of rigid posts.

(49) A pulley arrangement (814) is secured to end (816) of arm (812) distal to the excavator (810).

(50) One or more ropes (830) is threaded through the pulley arrangement (814) and in addition, the rope (830) is engaged to winch(es) (836) on the excavator (811). This forms a loop which extends around the secondary supports (820, 822, 824).

(51) A carriage, indicated by (840) is secured to the rope.

(52) The first end (252) of the chain (250) is connected to the carriage (840). This secures the grabbing device (100) to the carriage (840).

(53) In-use, each of the winches (836) is configured to feed out or draw in the rope(s) so as to cause the loop to cycle. The winches (836) may operate individually or concurrently in either direction of rotation. Thereby, the position of the carriage (840) can be adjusted vertically and/or horizontally. As a result, the operation of the winches (836) controls and facilitates movement of the carriage (840) between the arm (812) and the secondary support (824).

(54) The winches (836) are configured to selectively feed out one of the lengths of rope (830). As a result, the height of the carriage (840) can be adjusted. In other words, the hauler (810) and winches (836) facilitate lifting and lowering of the carriage (840).

(55) To engage a load of logs (870) the winches (836) are first used to position the carriage (840), and thereby the grabbing apparatus (100).

(56) The winches are engaged to lower the carriage and thereby the grabbing apparatus (100) so that the jaws (400, 500) come into contact with the logs (870).

(57) An operator (not shown) determines whether the grabbing device (100) is in an open position or a closed position. If in the closed position, then an opening cycle may be performed to move the first jaw (400) and the second jaw (500) into the open position to enable them to engage a log (870).

(58) The opening cycle involves lowering of the carriage (840) continues until the first body (200) and second body (300) substantially lie on the logs (870) or other surface such as the ground.

(59) Lowering of the carriage (840) is halted.

(60) An operator (not shown) engages remote control (not shown) to move the brake (700) to a release position.

(61) The spring (216) applies an urging force to axle (212) thereby causing it and the cog (210) to rotate. This causes the chain (242) to be fed through the guide (240). As a result, the first end (252) of the chain (250) moves with respect to the brake (700). Accordingly, the middle section, and potentially the first end (252), are fed through the guide (240) and past the brake (700).

(62) The operator uses the remote control to move the brake to an engaged or locking position. The actuator (750) causes the clamping band (720) to tighten around the drum (712). This prevents the axle (212) from rotating.

(63) The winches (836) are engaged to move the carriage (840) upwards (vertically). This causes the first end (252) to move upwards. Because the brake (700) engages the middle section of the chain (250) the first body (200) is also moved upwards.

(64) The chain does not hold the second body close to the first body (200). Rather, the middle section of the chain (250) is able to move around the cog, and the cog (210) rotates around the axle (212). The second body (300) moves away from the first body (200). This causes the jaws (400, 500) to pivot to a release (open) position.

(65) The grabbing device (100) is now in an open position.

(66) The winches (836) are engaged to lower the carriage (840) and thereby also grabbing device (100). The jaws (400, 500) touch one or more logs (870). The brake (700) is moved to a release position and the carriage (840) is raised by the rope loop. The chain moves up through the first body (100) decreasing the length of chain (250) between the first and second bodies (200, 300). This action causes link arms (410, 510) to force the jaws (400, 500) to pivot towards a closed position. The closed position may that in which the jaws (400, 500) touch one or more logs (870) or are completely closed (interlinked) as is shown in FIG. 8

(67) Decreasing the length of the chain (250) between the first and second bodies (200, 300) causes the cog (210) and thereby axle to be moved towards the first body (200). This causes the first jaw (400) to pivot about the axle (412) and second jaw (510) to pivot about the axle (512) to more the jaws into an engaged position.

(68) Forcing the first and second jaws into or towards a closed position may be assisted by the linkage arms (410, 510). That is, the linkage arms (410, 510) assist in forcing the jaws (400, 500) to pivot into or towards a closed position.

(69) The weight of the grabbing device (100) and logs (870) provides force to hold the jaws (400, 500) in a closed position. Therefore, the grabbing strength of the grabbing device (100) is independent of a biasing device or actuators such as hydraulic rams.

(70) The winches (836) can then be used to feed in or out the rope to thereby cause the loop to circulate to move the logs (870) to a desired location.

(71) To release the logs (870) from the grabbing device (100) the winches (836) are engaged so as to lower the grabbing device (100).

(72) This causes the logs (870) to be placed on the ground.

(73) The spring (216) can apply an urging force to axle (212) and thereby causes cog (210) to force the middle section of the chain (250) through the guide (240). This increases the amount of the chain (250) position between the first body (200) and the second body (300).

(74) The operator uses the remote control (not shown) to engage the brake (700). Accordingly, the brake engages the chain (250) between the first end (252) and the second end (254).

(75) The winches (836) are engaged to raise the carriage (840). As the first end (252) is fixed to the carriage (840), it is also raised. This causes the first body (200) to be raised.

(76) The link arms (410, 510) may assist in lifting the second body (300) as the first body (200) is also raised.

(77) The middle section of the chain (250) between the first body (200) and the second body (300) extends around the axle and carries the weight of the second body (300). The axles (412, 512) at which the linkage arms (410, 510) are attached to the first and second jaws (400, 500) are moved upwards.

(78) In this position, the chain (252) may carry the weight of the second body (300).

(79) This causes the first jaw (400) and the second jaw (500) to pivot towards a release (open) position as is shown in FIGS. 3-7.

(80) The above process can be repeated to move additional logs.

First Alternate Embodiment

(81) Referring now to FIGS. 12 and 13 showing a grabbing device (900) according to an embodiment of the invention.

(82) The grabbing device (900) is substantially identical to the grabbing device described above with reference to FIGS. 1-10. Accordingly, like references will be used to refer to like components.

(83) However, the first jaw (400) and second jaw (500) are mounted on the same axle (910). In doing so, the jaws (400, 500) are able to rotate in opposite directions to each other. That is, the first jaw (400) pivots in a clockwise direction, then the second jaw (500) can pivot in an anti-clockwise direction, and vice versa.

(84) The inventor has identified that mounting the first jaw (400) and the second jaw (500) on the same axle (910) may improve the stability of the grabbing device (900) over the embodiment shown and described with reference to FIGS. 1-10.

(85) It should be understood that all other aspects of the grabbing device (900) and its operation is equivalent to operation of grabbing device (100).

Second Alternate Embodiment

(86) Referring now to FIGS. 14-16 showing a grabbing device (1000) according to an embodiment of the invention.

(87) The grabbing device (1000) is substantially identical to the grabbing device described above with reference to FIGS. 1-10. Accordingly, like references will be used to refer to like components.

(88) In the embodiment of FIGS. 14-16 a chain guide (1100) is mounted in the first body (200). The chain guide (1100) replaces the first roller (242) and the second roller (244) in the embodiment of FIGS. 1-10.

(89) A side edge (1102) of the chain guide (1100) is shaped to define guide surface for the flexible length (250). The guide surface assists to keep the flexible length (250) in contact with the cog (210).

(90) The use of chain guide reduces moving parts and therefore may provide a more reliable grabbing device (1100).

(91) In the embodiment of FIGS. 14-16, a brake (1200) is provided by a locking member (1202) and a cog (1204).

(92) The cog (1204) is fixed to the axle (210) outside the first body portion, adjacent to an outer surface of the first body (200). The cog (1204) includes teeth (unnumbered in the Figures) which define recess or notches between adjacent teeth. The number of teeth and recesses/notches around the circumference of the cog may vary, as may their relative dimensions.

(93) An actuator (1206) is mounted to an outer surface of the first body (200). The actuator is configured to selectively move the locking member (1202) between an advanced position and a retracted position. In the advanced position, the locking member (1202) can engage one of the recesses/notches in the cog (1204). This engagement prevents the cog (1204) rotating relative to the first body. As the cog (1204) is fixed to the axle (212) engagement of a recess in the cog by the locking member also prevents rotation of the axle (212) and therefore movement of the flexible length (250) through the first body (200).

(94) In the retracted position, the locking member (1202) does not prevent rotation of the cog (1204), and preferably does not contact the cog (1204). Accordingly, when the locking member is in the retracted position the cog (1204) can rotate freely.

(95) The locking member (1202) may move linearly or through an arcuate path. For instance, the locking member (1202) may be pivotally mounted to the first body (200). In this embodiment, the actuator (1206) may be a linear actuator which expands and contracts to apply force to the locking member (1202), causing it to pivot about an axis to move between the extended and retracted position(s). The actuator (1206) may be a screw thread mechanism driven by an electric motor, or a hydraulic cylinder and ram.

(96) In contrast, the locking member (1202) may be mounted to the actuator (1206), and linear expansion or contraction of the actuator (1206) moves the locking member (1202) between the extended and retracted position(s).

(97) In addition, it should also be appreciated that the locking member (1202) may be provided by an end of the actuator, and therefore the discussion herein should not be seen as limiting.

(98) Use of a brake as illustrated in FIGS. 14 to 16 provides a number of predefined positions in which the cog (210) can be locked in position.

(99) The actuator (1206) may be in communication with a remote (note shown in FIGS. 14 to 16) to enable an operator to selectively engage the actuator (1206) to move the locking member (1202) between the extended and retracted positions.

(100) The invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, in any or all combinations of two or more of said parts, elements or features.

(101) Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof as defined in the appended claims.