FRONT ATTACHMENT IN TRAVELING MACHINE BODY FOR OPERATION

Abstract

To set time difference to the starting time of excavation and scooping by setting the starting of the scooping with a bucket behind the starting of the excavation with a ripper in an excavation machine where the bucket and the ripper are equipped to an arm, and are manipulated to open and close with each other by expansion and contraction of a hydraulic cylinder During the first half of the contracting process at a hydraulic cylinder, a pin mounted on a connecting link where a bucket and a ripper are connected moves through a slot formed on the bucket to make bucket delay in closing, and the bucket and the ripper close at the same time during the latter half of the contracting process.

Description

TECHNICAL FIELD

The present invention relates to the technical field of a front attachment in a traveling machine body for operation such as a hydraulic shovel.

BACKGROUND ART

Generally, in a known traveling machine body for operation such as a hydraulic shovel, a first operating body such as a bucket and a second operating body such as a ripper are provided as a front attachment to be openable and closable, such that a dug object dug with the second operating body is scooped with the first operating body and wood and the like is held (sandwiched) with the two operating bodies (e.g., see PTL 1 and 2).

CITATION LIST

Patent Literature

[PTL 1]

Japanese Utility Model Application Laid-open No. H2-136148

[PTL 2]

Japanese Patent No. 4936784

SUMMARY OF INVENTION

Technical Problem

However, since the configuration in PTL 1 is such that a dedicated hydraulic cylinder is provided to each of the respective operation arms to open or close the two operating bodies, there is a problem in that the number of parts becomes large and that tremendous burden is placed particularly on an inexperienced operator due to a troublesome manipulation being required for a complicated mechanism for separately operating the two hydraulic cylinders.

In contrast, in PTL 2, an opening or closing operation of the two operating bodies is performed with one hydraulic cylinder, thereby overcoming the drawback of PTL 1 described above such as the number of parts becoming large or the burden on an operator being large. However, the opening or closing operation of the two operating bodies are simultaneous in the case of an extending or contracting operation of the hydraulic cylinder herein, and therefore, despite there being not much trouble in the case of a simple holding operation, there is a problem of a disadvantage in operation performance due to a scooping operation being too early in the case where two operations are involved such as the first operating body scooping an object dug with the second operating body; here lies the problem to be solved by the present invention.

Solution to Problem

The present invention has been created for the purpose of solving these problems in view of the circumstances as described above. An invention of claim 1 is a front attachment in a traveling machine body for operation, including: a first operating body provided to be swingable at a tip end section of an arm; a second operating body provided to be swingable at an intermediate section of the arm; a hydraulic cylinder of which a base end section is provided to the arm and a tip end section is provided to a base end section of the second operating body; and a connecting link that connects the first operating body and the second operating body, the first operating body and the second operating body being configured to perform an opening or closing operation along with an extending or contracting operation of the hydraulic cylinder, wherein operation delaying means for delaying a closing operation of the first operating body by causing the second operating body to perform a closing operation in advance in a process of contracting the extended hydraulic cylinder is provided to a connecting section for the first operating body and the connecting link.

An invention of claim 2 is the front attachment in a traveling machine body for operation according to claim 1, wherein the operation delaying means includes a slot provided to the first operating body and a pin provided to the connecting link to be movable in the slot, and is configured to cause only the second operating body to perform the closing operation in advance by the pin moving in the slot in a first half of the process of contracting the hydraulic cylinder, and cause both of the first operating body and the second operating body to perform the closing operation in a second half of the process of contracting the hydraulic cylinder after the pin has moved to a moving end of the slot, thus delaying the closing operation of the first operating body with respect to the closing operation of the second operating body.

An invention of claim 3 is the front attachment in a traveling machine body for operation according to claim 1 or 2, wherein the first operating body is a bucket, and the second operating body is a ripper.

Advantageous Effects of Invention

With the invention of claim 1, the second operating body first performs the closing operation alone, and then the first and second operating bodies perform the closing operation together, in the process of contracting the one hydraulic cylinder. As a result, smoothly performing an operation with a time lag such as the first operating body scooping an object dug with the second operating body can be easy even for an inexperienced operator. With the invention of claim 2, the operation delaying means for delaying the closing operation of the first operating body by causing the second operating body to perform the closing operation in advance can be configured easily.

With the invention of claim 3, an object first dug with the ripper can be scooped with the bucket with a time lag, in the digging of hard soil. Thus, the operation performance is improved, and early wear of the bucket as in the case where the bucket performs all of such digging and scooping operations can be avoided.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an overall side view of a hydraulic shovel.

FIG. 2 is a side view of a front attachment.

FIG. 3 is a perspective view of the main section of the front attachment.

FIG. 4 is a side view showing a state where a hydraulic cylinder has extended maximally when an arm is in a crowding posture.

FIG. 5 is a side view showing a state where the hydraulic cylinder has contracted and a pin has moved to a moving end of a slot when the arm is in the crowding posture.

FIG. 6 is a side view showing a state where the hydraulic cylinder has contracted maximally when the arm is in the crowding posture.

FIG. 7 is a side view showing a state where the hydraulic cylinder has extended maximally when the arm is in a perpendicular posture.

FIG. 8 is a side view showing a state where the hydraulic cylinder has contracted and the pin has moved to a moving end of the slot when the arm is in the perpendicular posture.

FIG. 9 is a side view showing a state where the hydraulic cylinder has contracted maximally when the arm is in the perpendicular posture.

FIG. 10 is a side view showing a state where the hydraulic cylinder has extended maximally when the arm is in a dump posture.

FIG. 11 is a side view showing a state where the hydraulic cylinder has contracted and the pin has moved to the moving end of the slot when the arm is in the dump posture.

FIG. 12 is a side view showing a state where the hydraulic cylinder has contracted maximally when the arm is in the dump posture.

DESCRIPTION OF EMBODIMENTS

An embodiment for carrying out the present invention will be described below based on the drawings. In the drawings, 1 denotes a traveling machine body of a hydraulic shovel. In the traveling machine body 1, an upper slewing body 3 is mounted on a crawler-type lower traveling body 2 to be capable of slewing about a vertical axis. In the upper slewing body 3, the configuration including various member devices such as a front operation section 4, an operator's cab (cab) 5, an engine room 6, and a counterweight 7, which are to be described later, is in accordance with the prior art.

The front operation section 4 is provided with a boom 8 of which the base end section is axially supported to be rotatable at the upper slewing body 3 and that is moved up and down by an extending or contracting operation of a boom cylinder 8a, an arm (stick) 9 that is axially supported to be rotatable at the tip end section of the boom 8 with a supporting shaft 9a and moved dump and crowd by an extending or contracting operation of an arm cylinder 9b, and a front attachment A with which the present invention is carried out at the tip end section (front end section) of the arm 9. The front attachment A is configured as follows. First, a bucket (corresponding to “first operating body” of the present invention) 10 axially supported to be rotatable at the tip end section of the arm 9 with a supporting shaft 10a is provided, and the intermediate section of a ripper (corresponding to “second operating body” of the present invention) 11 is axially supported to be swingable at the intermediate section of the arm 9 in the length direction with a first supporting shaft 11a. In the ripper 11, a claw section 11b for breaking a hard ground surface or bedrock is provided on the traveling machine body 1 side (rear side) to oppose an opening section 10b of the bucket 10. The claw section 11b may obviously be one-clawed or be in a forked shape that is branched to be, for example, two-clawed, three-clawed, or the like.

The ripper 11 is provided with a base end section 11c that extends to the opposite side (front side) of the bucket opening section 10b. The base end section 11c is axially supported to be swingable with a second supporting shaft 12c at the tip end section of a rod 12b of a hydraulic cylinder 12 that is axially supported at the base end section of the arm 9 with a first supporting shaft 12a and provided such that the rod 12b protrudes forward. Further, one end section of a connecting link 13 is axially supported to be swingable with a second supporting shaft 11d at the intermediate section on the claw section 11b side of the ripper 11. The other end section (front end section) of the connecting link 13 is provided with a pin 13a. The pin 13a penetrates and is supported to be movable at a slot (corresponding to “operation delaying means” of the present invention) 10d provided to a base end section 10c protruding to the opposite side (front side) of the main body of the bucket 10. In this embodiment, the slot 10d is formed by being cut into an upwardly inclined shape, for example on a tangent C, to deviate from an arc B of which the shaft center is the bucket supporting shaft 10a. As a reference, in the case where the slot 10d is formed along the arc B, support by a slot upper-side circumferential edge 10g by the pin 13a as described later is lost. Therefore, the bucket 10 is rotated by its own weight in accordance with the contraction of the hydraulic cylinder, and the present invention is not possible.

Herein, in a perpendicular posture in which the bucket supporting shaft 10a is located on a perpendicular (arm perpendicular) D from the arm supporting shaft 9a as shown in FIG. 7, a bucket gravity center E is located in the front relative to the arm perpendicular D. In this state, the bucket 10 tries to rotate rearward with its own weight. Accordingly, the bucket 10 is maintained in a posture in which the pin 13a contacts an upper end 10e of the slot 10d.

FIGS. 4 to 6 show the motion of the front attachment A upon causing an extending or contracting movement of the hydraulic cylinder 12, in the case of the bucket supporting shaft 10a being located on the traveling machine body 1 side (rear side) relative to the perpendicular (arm perpendicular) D from the arm supporting shaft 9a (an arm crowding posture). When the hydraulic cylinder 12 is in a maximally extended state (see FIG. 4), the setting is such that the bucket gravity center E of the bucket 10 is located on a perpendicular (bucket perpendicular) K from the bucket supporting shaft 10a within a range of the slot 10d. The setting is such that, accordingly, the bucket 10 sinks from a posture (posture of a virtual line in FIG. 4) in which the pin 13a contacts the slot upper end 10e to be located in an intermediate position of the slot 10d.

When the hydraulic cylinder 12 is contracted from this state, the cylinder second supporting shaft 12c is located at the intersection of a center line F of the hydraulic cylinder 12 and an arc G of which the center is the first supporting shaft 11a. In the ripper 11 at this time, the claw section 11b swings toward the lower side with the first supporting shaft 11a as a fulcrum in a state of coordination with the arc G. Meanwhile, the second supporting shaft 11d swings on an arc H with the first supporting shaft 11a as a fulcrum. Then, the connecting link 13 moves in coordination with the swing of the second supporting shaft 11d. The pin 13a is brought to a state of being supported at an upper-side circumferential edge 10g of the slot 10d and moves toward a lower end (front end) 10f of the slot 10d. During the first half of a contracting process until the pin 13a contacts the slot lower end 10f (see FIG. 5), the pin 13a pushes the slot lower end 10f forward, so that a scooping operation of the bucket 10 is absent. During this time, the scooping operation of the bucket 10 is delayed, and only the ripper 11 performs a digging operation with a lower-side swing of the claw section 11b, with the first supporting shaft 11a serving as a fulcrum.

During the second half of the contracting process from this state until the hydraulic cylinder 12 is further contracted and moved to a maximally contracted state (see FIG. 6), the ripper 11 swings downward along the arc H of the second supporting shaft 11d to continue the swing operation of the ripper 11. Simultaneously, the pin 13a pushes the slot lower end 10f forward and downward up to an intersecting position of an arc I of which the center is the ripper second supporting shaft 11d and an arc J of which the center is the bucket supporting shaft 10a, so that the bucket 10 performs the scooping operation in which the opening section 10b moves upward. Accordingly, the posture is such that the ripper claw section 11b covers the bucket opening section 10b.

Next, FIGS. 7 to 9 show the motion of the front attachment A upon causing an extending or contracting movement of the hydraulic cylinder 12, in the case of the bucket supporting shaft 10a being located on the perpendicular K from the arm supporting shaft 9a (an arm perpendicular posture). (Hereinafter, description relating to the arc or the like is the same and therefore omitted.) In a state where the hydraulic cylinder 12 is maximally extended (see FIG. 7), the bucket 10 is in a posture in which the bucket gravity center E is located in the front relative to the arm perpendicular D. Accordingly, the bucket 10 tries to rotate toward the arm perpendicular D side with its own weight and is in a posture in which the pin 13a contacts the slot upper end 10e.

In the ripper 11, when the hydraulic cylinder 12 is contracted from this state, the claw section 11b swings toward the lower side with the first supporting shaft 11a as a fulcrum, while the second supporting shaft 11d swings with the first supporting shaft 11a as a fulcrum. The bucket 10 is brought to a state where the pin 13a is supported at the upper-side circumferential edge 10g of the slot 10d, and the pin 13a moves toward the lower end (front end) 10f of the slot 10d. During the first half of a contracting process until the pin 13a contacts the slot lower end 10f (see FIG. 8), the pin 13a pushes the slot lower end 10f forward, so that a scooping operation of the bucket 10 is absent. During this time, the scooping operation of the bucket 10 is delayed, and only the ripper 11 performs a digging operation with a lower-side swing of the claw section 11b, with the first supporting shaft 11a serving as a fulcrum.

During the second half of the contracting process from this state until the hydraulic cylinder 12 is further contracted and moved to a maximally contracted state (see FIG. 9), the swinging operation of the ripper 11 is continued. Simultaneously, the pin 13a pushes the slot lower end 10f forward and downward, so that the bucket 10 performs the scooping operation in which the opening section 10b moves upward. Accordingly, the posture is such that the ripper claw section 11b covers the bucket opening section 10b.

Further, FIGS. 10 to 12 show the motion of the front attachment A upon causing an extending or contracting movement of the hydraulic cylinder 12, in the case of the bucket supporting shaft 10a being located on the front side relative to the arm perpendicular D (an arm dump posture). In a state where the hydraulic cylinder 12 is maximally extended (see FIG. 10), the bucket 10 is in a posture in which the bucket gravity center E is located in the front relative to the arm perpendicular D. Accordingly, the bucket 10 tries to rotate toward the arm perpendicular K side with its own weight and is in a posture in which the pin 13a contacts the slot upper end 10e.

In the ripper 11, when the hydraulic cylinder 12 is contracted from this state, the claw section 11b swings toward the lower side with the first supporting shaft 11a as a fulcrum, while the second supporting shaft 11d swings with the first supporting shaft 11a as a fulcrum. The bucket 10 is brought to a state where the pin 13a is supported at the upper-side circumferential edge 10g of the slot 10d, and the pin 13a moves toward the lower end (front end) 10f of the slot 10d. During the first half of a contracting process until the pin 13a contacts the slot lower end 10f (see FIG. 11), the pin 13a pushes the slot lower end 10f forward, so that a scooping operation of the bucket 10 is absent. During this time, the scooping operation of the bucket 10 is delayed, and only the ripper 11 performs a digging operation with a lower-side swing of the claw section 11b, with the first supporting shaft 11a serving as a fulcrum.

During the second half of the contracting process from this state until the hydraulic cylinder 12 is further contracted and moved to a maximally contracted state (see FIG. 12), the swing operation of the ripper 11 is continued. Simultaneously, the pin 13a pushes the slot lower end 10f forward and downward, so that the bucket 10 performs the scooping operation in which the opening section 10b moves upward. Accordingly, the posture is such that the ripper claw section 11b covers the bucket opening section 10b.

In the case where the extended hydraulic cylinder 12 is contracted in a configuration in which the bucket 10 and the ripper 11 are provided to the arm 9 in the embodiment for carrying out the present invention configured as described above, the pin 13a provided to the connecting link 13 that connects the bucket 10 and the ripper 11 moves in the slot 10d provided to the bucket 10 from the upper end 10e (or midway) to the lower end 10f in the first half of a contracting process. In this first half of the contracting process, a delaying posture in which a scooping swing of the bucket 10 is not performed and stopped is maintained, and the claw section 11b of the ripper 11 moves downward (moves to the closing side) to perform a digging operation.

In the second half of the contracting process after the pin 13a has reached the lower end 10f of the slot 10d, the downward movement of the ripper 11 on the closing side is continued, and the pin 13a contacts the slot lower end 10f to press the base end section 10c of the bucket 10 to the front side. The bucket 10 performs a scooping operation in which the opening section 10b moves upward, and the ripper 11 operates to close the bucket opening section 10b.

When the present invention is carried out in this manner, the bucket 10 and the ripper 11 perform an opening or closing operation in coordination with an extending or contracting operation of the one hydraulic cylinder 12. In the first half of a contracting process of the hydraulic cylinder in this case, only the ripper 11 performs a closing operation, and the bucket 10 maintains a delaying posture to remain stopped. In the second half of the contracting process after the pin 13a has reached the front end 10f that is a moving end of the slot 10d, the bucket 10 also performs a closing operation together with the ripper 11. That is, in the process of contracting the one hydraulic cylinder 12, the bucket 10 performs the closing operation subsequently in a state where there is a time lag with respect to the ripper 11, and a dug object dug by a digging operation can be subjected to a scooping operation with the bucket 10 subsequently in a delayed state with a time lag. A sequence of digging and scooping operations can be performed in a state of having a time lag, and the operation performance is improved.

Since the digging operation by the ripper 12 and the scooping operation by the bucket 10 with a time lag can be performed with an extending or contracting operation of the one hydraulic cylinder 12, simplification of structure can be achieved, and manipulation can be easy even for an inexperienced operator.

Moreover, in the case of digging hard soil, soil dug with the ripper 12 is scooped with the bucket 10. Therefore, wear of the bucket 10 can be reduced compared to a case where both of the digging and scooping operations are performed with the bucket 10 alone.

Moreover, in a configuration of delaying the closing operation of the bucket 10 with respect to the closing operation of the ripper 11 herein, the pin 13a provided to the connecting link 13 that connects the bucket 10 and the ripper 11 can move in the slot 10d provided to the bucket 10. Thus, the configuration of a delaying mechanism is simple.

The present invention is obviously not limited to the embodiment. The bucket can be replaced with an operating body such as a ripper. The delaying mechanism can be carried out with a slot being provided to a connecting link and a pin being provided to a bucket.

As a reference, the shape of the slot 10d is determined based on the first half of a contracting operation of the hydraulic cylinder 12 from a maximally extended state. By determining the respective positions of the upper end (base end) 10e and the lower end (tip end) 10f of the slot 10d that the pin 13a contacts in that case and connecting the positions with a line, the bucket can be set to not swing in the first half of the contracting process. The tangent as in the embodiment is obviously not limiting.

INDUSTRIAL APPLICABILITY

The present invention can be utilized as a front attachment provided to a traveling machine body for operation such as a hydraulic shovel.

Claims

1. A front attachment in a traveling machine body for operation, comprising: a first operating body provided to be swingable at a tip end section of an arm;a second operating body provided to be swingable at an intermediate section of the arm;a hydraulic cylinder of which a base end section is provided to the arm and a tip end section is provided to a base end section of the second operating body;a connecting link that connects the first operating body and the second operating body,the first operating body and the second operating body being configured to perform an opening or closing operation in response to an extending or contracting operation of the hydraulic cylinder; andoperation delaying means for delaying a closing operation of the first operating body by causing the second operating body to perform a closing operation in advance in a process of contracting the extended hydraulic cylinder provided to a connecting section for the first operating body and the connecting link.

2. The front attachment in a traveling machine body for operation according to claim 1, wherein the operation delaying means includes a slot provided in the first operating body anda pin provided to the connecting link to be movable in the slot, and configured to cause only the second operating body to perform the closing operation in advance by the pin moving in the slot in a first period of contracting the hydraulic cylinder, and cause both of the first operating body and the second operating body to perform the closing operation in a second period of contracting the hydraulic cylinder after the pin has moved to an end of the slot.

3. The front attachment in a traveling machine body for operation according to claim 1, wherein the first operating body is a bucket, and the second operating body is a ripper.