JP2013167107A - Expansion rod and deep drilling machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an expansion rod with a built-in telescopic cylinder and a deep drilling machine, capable of securing the mounting strength of the telescopic cylinder in a simple structure and capable of preventing the fall of the expansion rod and an open/closed bucket when the expansion rod is broken, respectively.SOLUTION: An expansion rod 18 comprises: an upper bracket 20 provided at the upper end of an outer cylinder 18a and connected to an arm with a pin; and a lower bracket 21 provided at the lower end of an inner cylinder 18b and connected with the open/closed bucket with a pin. The brackets 20, 21 have openings 20e, 21e passing through expansion rod 18 in the expanding direction. Through the opening 20e of the upper bracket 20, the bottom side end of a telescopic cylinder 17 is inserted to be connected to the upper bracket 20 with a pin 23. Through the opening 21e of the lower bracket 21, the rod end of the telescopic cylinder 17 is inserted to be connected to the lower bracket with a pin.

Description

  The present invention relates to a telescopic rod attached to a arm of a self-propelled working machine and a deep excavator using the same.

  For example, Patent Document 1 discloses an excavator that performs excavation by attaching an extendable rod from an arm of a self-propelled working machine and attaching a clamshell bucket to the lower end of the extendable rod. The telescopic rod used in such an excavator accommodates an internal telescopic cylinder consisting of a hydraulic cylinder, and connects one end of the telescopic cylinder to the can part of the outer cylinder constituting the telescopic rod with the other end. It is connected and attached to the can part of the inner cylinder by a pin.

Japanese Utility Model Publication No. 3-30436

  However, according to the conventional structure in which the expansion cylinder accommodated in the expansion / contraction rod is connected to the cylindrical expansion / contraction rod can portion by the pin as described above, the plate thickness of the expansion / contraction rod can portion is limited by the standard, etc. For the reason, it is difficult to obtain the strength required for the telescopic cylinder connecting portion with the structure of the telescopic rod as it is. For this reason, the reinforcing plate is welded to the can portion to form the connecting portion of the telescopic cylinder, but there is a problem that the structure becomes complicated.

  In view of the above problems, an object of the present invention is to provide a telescopic rod with a built-in telescopic cylinder that can secure the mounting strength of the telescopic cylinder with a simple structure.

The telescopic rod of claim 1
A telescopic rod that is attached to the arm of a self-propelled working machine, has an openable bucket attached to the lower end, fits the outer cylinder and the inner cylinder so that they can be expanded and contracted, and houses the expansion cylinder inside In
The expansion / contraction direction of the telescopic rod to an upper bracket provided at the upper end of the outer cylinder and connected to the arm by a pin, and a lower bracket provided to the lower end of the inner cylinder and connected to the openable bucket by a pin, respectively An opening that penetrates the
One end of the telescopic cylinder is inserted into the opening provided in the upper bracket and connected to the upper bracket by a pin,
The other end of the telescopic cylinder is inserted into the opening provided in the lower bracket and connected to the lower bracket by a pin.

The telescopic rod according to claim 2, wherein the telescopic rod according to claim 1,
The outer cylinder and the inner cylinder are rectangular in cross section,
The direction of the pin hole of the upper bracket connected to the arm is orthogonal to the direction of the pin hole of the lower bracket connected to the openable bucket.

The telescopic rod according to claim 3 is the telescopic rod according to claim 1 or 2,
A stopper is provided on the inner surface of the lower end of the outer cylinder to prevent the inner cylinder from coming off,
The outer surface of the upper end portion of the inner cylinder is provided with a locking member that comes into contact with the stopper and prevents the inner cylinder from coming off.

The telescopic rod according to claim 4 is the telescopic rod according to any one of claims 1 to 3,
A block to which a hydraulic hose extending from the arm side is detachably connected to an upper portion of the outer cylinder is provided,
In the block, there is provided a branch path that branches into an oil path to the telescopic cylinder and an oil path to the open / close type bucket, and in the block, the open / close operation of the open / close type bucket is expanded and contracted by the telescopic cylinder. It is characterized by providing a sequence valve to be performed in advance.

  A deep excavator according to a fifth aspect is characterized in that the telescopic rod according to any one of the first to fourth aspects is attached to a tip of a telescore as the arm.

  According to the first aspect of the present invention, the arm side end of the telescopic cylinder built in the telescopic rod is connected to the upper bracket of the telescopic rod by a pin, and the rod side end is connected to the lower bracket which is an openable bucket connecting part of the telescopic rod. Since the upper bracket and the lower bracket were originally provided with high strength for connection, a complicated structure such as welding of a reinforcing member for connecting the telescopic cylinder is required. The connecting portion of the telescopic cylinder can be configured with a simple structure.

  In addition, since the extension cylinder is protected by the extension rod, the extension cylinder is prevented from being damaged.

  In addition, since both ends of the telescopic cylinder are connected to the upper and lower brackets of the telescopic rod, it is possible to increase the telescopic stroke of the telescopic rod.

  In the invention of claim 2, since the cross-sectional shape of the outer cylinder and the inner cylinder is rectangular, the inner cylinder is not twisted with respect to the outer cylinder as in the case of a circular shape. For this reason, excessive force does not act by the kinking of the open / close bucket hydraulic hose attached to the telescopic rod, and damage to the hydraulic hose is prevented.

  In addition, by connecting a connector provided on the outer periphery of the tube to be connected to the rod chamber of the telescopic cylinder at the corner portion of the inner cylinder, the outer cylinder and the inner cylinder can be made smaller than a circular shape. it can. In addition, since the direction in which the telescopic rod is connected to the arm and the open / close bucket is crossed, the open / close bucket and the telescopic rod can be swung by an external force acting on the open / close bucket. Excessive force is prevented from being applied to the telescopic rod, and these damages are prevented. Moreover, since compatibility with the existing suspension bracket is ensured, it can be used as a retrofitted attachment.

  According to a third aspect of the present invention, a stopper for preventing the inner cylinder from coming off is provided on the inner surface of the lower end portion of the outer cylinder, and a locking member for coming into contact with the stopper to prevent the inner cylinder from coming off is provided on the outer surface of the upper end portion of the inner cylinder. Since it is provided, even if the telescopic cylinder breaks, the inner cylinder is not detached from the outer cylinder, and the fall of the openable bucket is prevented, so that safety is improved.

According to the invention of claim 4, a block to which a hydraulic hose extending from the arm side is detachably connected is provided at the upper part of the outer cylinder, and an oil path to the telescopic cylinder and an oil to the open / close bucket are provided in this block. A branch path that branches into a path, a sequence valve that sets the operation order of the openable bucket and the telescopic cylinder are provided. With such a structure, when the telescopic rod is newly attached to an existing arm, it is possible to connect the hydraulic hose attached to the arm in advance to the block as it is, and the existing hydraulic hose remains as it is. It becomes possible to use, and it becomes easy to apply to existing telescores.

  According to a fifth aspect of the present invention, the telescopic rod according to any one of the first to fourth aspects is attached to a telescore, and the effect of the configuration of the telescopic rod having the characteristics described above can be obtained.

It is a side view which shows one Embodiment of the deep excavation machine by this invention in a excavation operation state. In the deep excavation machine of this Embodiment, it is a side view which shows the state which has loaded earth and sand into the conveyance vehicle. It is a side view which shows the connection structure of the expansion-contraction cylinder and bucket of this Embodiment. It is a side view which shows an example of a structure of the clamshell bucket of this Embodiment. (A) is the front view which shows the expansion-contraction rod of this Embodiment in a contracted state, (B) is the right view. (A) is the left view which shows the expansion-contraction rod of this Embodiment in a contracted state, (B) is the longitudinal cross-sectional view. (A) is a bottom view of the telescopic rod of the present embodiment, and (B) is an EE cross-sectional view of FIG. 5 (A). (A) and (B) are the G section and H section expanded sectional views of Drawing 6 (B), respectively. (A) is the front view which shows the expansion-contraction rod of this Embodiment in the expansion | extension state, (B) is the right view. (A) is the left view which shows the expansion-contraction rod of this Embodiment in the expansion | extension state, (B) is the longitudinal cross-sectional view. It is the J section expanded sectional view of Drawing 10 (B). It is an example of the hydraulic circuit for expansion-contraction of the expansion-contraction rod of this Embodiment, and a bucket opening and closing. It is a side view which shows the other example of the working machine using the expansion-contraction rod of this Embodiment.

  1 and 2 are side views showing an example of a deep excavator to which the telescopic rod according to the present invention is applied, in an excavation state and a state in which sediment is loaded into a transport vehicle. In FIGS. 1 and 2, reference numeral 1 denotes a lower traveling body, and 3 an upper revolving body installed on the lower traveling body 1 via a revolving device 2. The upper swing body 3 is configured by mounting a hydraulic power unit 4, a cab 5, a counterweight 6, and the like on a swing frame 3a. The lower traveling body 1 and the upper turning body 2 constitute an excavator body that is a self-propelled vehicle. As shown in FIG. 1, the cab 5 can be moved back and forth, and the cab 5 is moved forward during excavation work so that an operator in the cab 5 can visually observe the excavation site in the vertical hole 7. ing.

  A boom 8 is attached to the revolving frame 3a by a boom cylinder 9 so that it can be raised and lowered. Reference numeral 10 denotes a telescore, and in this example, the telescore 10 is directly attached to the boom 8, but a non-expandable arm (not shown) may be attached.

  This telescoreme 10 is configured by combining an outer arm 10a, a center arm 10b, and an inner arm 10c in a telescopic manner. As shown in FIG. 2, the telescore 10 has an outer arm 10 a connected to the tip of the boom 8 by a pin 11, and both ends connected to the outer arm 10 a and the boom 8 by pins 12 and 13. And the inclination angle of the telescore 10 with respect to the boom 8 can be changed by the expansion and contraction of the arm cylinder 14.

  Reference numeral 16 denotes a clamshell bucket, reference numeral 18 denotes a telescopic rod provided between the inner arm 10 c of the telescoreme 10 and the clamshell bucket 16, and reference numeral 17 denotes a telescopic cylinder composed of a hydraulic cylinder built in the telescopic rod 18.

  FIG. 3 is an enlarged side view showing the structure of the clamshell bucket (hereinafter referred to as a bucket) 16 and the telescopic rod 18. As shown in FIG. 3, the telescopic rod 18 is formed by combining the inner cylinder 18b with the outer cylinder 18a so as to extend and contract. The upper bracket 20 is fixed to the upper end of the outer cylinder 18a by welding or the like. The upper bracket 20 is connected to the inner arm 10c of the telescore 10 so that the telescopic rod 18 can swing back and forth by a pin 19 directed to the left and right. A lower bracket 21 is fixed to the lower end of the inner cylinder 18b by welding or the like, and the bucket 16 is connected to the telescopic rod 18 so as to be able to swing left and right by a pin 22 facing forward and backward.

  The telescopic cylinder 17 is connected to the upper bracket 20 by a pin 23 whose bottom end is directed in the left-right direction. The rod side end of the telescopic cylinder 17 is connected to the lower bracket 21 by a pin 24 directed in the front-rear direction.

  In this configuration, when the telescopic cylinder 17 is contracted, the bottom of the bucket 16 is in the raised position indicated by H, and when the telescopic cylinder 17 is extended, it is in the lowered position indicated by L, and the length of the telescopic cylinder 17 is added. Deep digging is possible.

  FIG. 4 shows the structure of the bucket 16. The bucket 16 of this embodiment is provided with a bucket cylinder 36 at the center. The bucket cylinder 36 is externally fitted so that a tube 36c can be moved up and down with respect to a rod 36b having a piston 36a fixed to an intermediate portion. It has a structured. The rod 36b also serves as a support for the shell 41 described later. The bucket cylinder 36 includes an open side chamber (oil chamber that supplies hydraulic oil when the bucket 16 is opened) 36d and a closed side chamber (hydraulic oil when the bucket 16 is closed) that are sealed above and below the piston 36a in the tube 36c. Oil chamber) 36e is formed.

  The frame 40 is fixed to the lower end of the rod 36b of the bucket cylinder 36 by welding or the like. A pair of shells 41 and 41 are pivotally attached to the frame 40 by pins 42 and 42 so as to be opened and closed. 43 is a connecting arm that opens and closes the shell 41 by the vertical movement of the tube 36c. These connecting arms 43 are connected to the tube 36c by a pin 44 and the lower end is connected to the shell 41 by a pin 45.

  Next, details of the telescopic rod 18 will be described with reference to FIGS. 5 to 8 show a state where the telescopic rod 18 is contracted, and FIGS. 9 to 11 show a state where the telescopic rod 18 is extended.

  As shown in FIG. 7B, the outer cylinder 18a and the inner cylinder 18b of the telescopic rod 18 have a rectangular cross-sectional shape. As shown in FIGS. 5 and 6, the upper bracket 20 includes an end plate 20a welded to the upper end surface of the outer cylinder 18a, and a connecting portion 20b composed of two parallel plates welded to the end plate 20a. It consists of. As shown in FIG. 6A, the connecting portion 20b includes a pin hole 20c for connecting to the telescore 10 by the pin 19, and an end portion on the tube 17a (see FIG. 6B) side of the telescopic cylinder 17. Are connected to each other by a pin 23.

  As shown in FIG. 6B, the end plate 20a is provided with an opening 20e that opens in the direction of expansion and contraction of the telescopic rod 18, and the tube 17a side end of the expansion and contraction cylinder 17 is inserted into the opening 20e. The boss at the side end is connected to the connecting portion 20 b by the pin 23.

  Further, as shown in FIGS. 5 and 6, the lower bracket 21 is composed of an end plate 21a welded to the lower end surface of the inner cylinder 18b and two parallel plates welded to the end plate 21a. Part 21b. As shown in FIG. 5A, the connecting portion 21b has a pin hole 21c for connecting the bucket 16 with the pin 22 and an end portion of the rod of the telescopic cylinder 17 (see FIG. 6B) as a pin. 24 and a pin hole (not shown) for connection.

  As shown in FIG. 6B, the end plate 21a is provided with an opening 21e that opens in the expansion / contraction direction of the expansion / contraction rod 18, and the rod 17b side end of the expansion / contraction cylinder 17 is inserted into the opening 21e. The end boss is connected to the connecting portion 21b by a pin 24.

  In FIGS. 5 and 6, reference numeral 25 denotes a hydraulic pipe connecting block which is fixed to the upper side surface of the outer cylinder 18a by bolting or the like. The block 25 has connection ports 25a (see FIG. 6B) for connecting the other end of a hydraulic hose (not shown) having one end connected to the inner arm 10c of the telescore 10 on both sides. . This block 25 incorporates sequence valves 58A, 58B, 58C1, 58C2 and check valves 62, 65, etc., which will be described later in FIG.

  5 (A) and 6 (B), reference numeral 26 denotes a hydraulic hose that connects the block 25 and the bottom chamber in order to supply hydraulic oil to the bottom chamber of the telescopic cylinder 17, and 27 denotes the block 25 and the hydraulic cylinder 17. It is a hydraulic hose that connects the connector 28 provided at the end portion on the tube 17a side. Reference numeral 29 denotes a cover attached to the front surface of the outer cylinder 18a so as to protect the hydraulic hoses 26 and 27. In FIG. 6 (B), 30 supplies hydraulic oil to the rod chamber of the expansion / contraction cylinder 17, and therefore, between the connection tool 28 and the connection tool 31 provided at the rod side end of the tube 17 b of the expansion / contraction cylinder 17. Hydraulic piping to be connected.

  In FIGS. 5A and 6A, 32a and 32b are hydraulic hoses for connecting the block 25 and a connector 34 provided at the lower end of the outer cylinder 18a. These hydraulic hoses 32a and 32b are buckets. The hydraulic oil is supplied to the 16 oil chambers 36d and 36e.

  In FIG. 5A, reference numeral 77 denotes a hydraulic pipe connector provided in a pair with the connection tool 34 at the lower end of the inner cylinder 18b, and the connection tool 34 attached to the lower end of the outer cylinder 18a and this connection. The tool 77 is connected via hydraulic hoses 79a and 79b (see FIG. 7B) provided so as to pass through the hose guide 78 shown in FIGS. 5A and 6B. These hydraulic hoses 79a and 79b are connected to the hydraulic hoses 32a and 32b, respectively. The hose guide 78 is formed by connecting adjacent ones of box-shaped pieces through which the hydraulic hoses 79a and 79b pass so that they can be bent by a predetermined angle. The hose guide 78 has one end connected to one side of the lower end of the outer cylinder 18a and the other end connected to the lower end of the inner cylinder 18b by a mounting plate 82 as shown in FIGS. 5 (A) and 5 (B). It is done.

  5A and 6A, reference numerals 80 and 81 denote guide frames provided on both sides of the front surface of the outer cylinder 18a in order to guide the hose guide 78. These guide frames 80 and 81 are attached by protective frames 84 and 85 attached to the front surface of the outer cylinder 18a. The protective frames 84 and 85 serve to protect the hose guide 78 when the telescopic rod 18 collides with any object. Reference numeral 83 denotes a cover attached to the front surface of the outer cylinder 18a so as to cover the block 25 and the U-shaped curved portion 78a of the hose guide 78 (see FIGS. 6A and 6B). A protective frame 86 is also attached to the front surface of the cover 83. Further, as shown in FIGS. 6A, 7A, and 7B, a protective frame 87 is also provided on the side surface of the outer cylinder 18a to which the hydraulic hoses 32a and 32b are attached. 7A, reference numerals 88 and 89 denote connection pipes for connecting hydraulic hoses (not shown) connected to the oil chambers 36d and 36e of the bucket 16, respectively.

  Next, a mechanism for preventing the bucket 16 from dropping when the telescopic cylinder 17 is damaged will be described. FIG. 8A is an enlarged cross-sectional view of the G portion of FIG. 6B. As shown in this figure, a slide plate 90 that slides on the inner surface of the outer cylinder 18a is provided on the upper outer surface of the inner cylinder 18b. By being sandwiched between upper and lower stoppers 91 welded to 18b, the expansion rod 18 is prevented from moving in the expansion / contraction direction, and fixed to the inner cylinder 18b with bolts 92 and nuts 93, so Direction) is provided to prevent movement. In this example, as shown in FIG. 7B, two slide plates 90 are provided on each of the four surfaces of the inner cylinder 18b.

  FIG. 8B is an enlarged cross-sectional view of the H portion of FIG. 6B. As shown in FIG. 8B, a slide plate 95 that slides by contacting the outer surface of the inner cylinder 18b against the lower inner surface of the outer cylinder 18a. However, a welding member (not shown) welded to the inner surface of the outer cylinder 18a so as to sandwich the slide plate 95 by a U-shaped stopper 98 fixed to the mounting plate 96 welded to the outer surface of the outer cylinder 18a by a bolt 97. Thus, it is attached in a state in which movement in the left-right direction (perpendicular to the paper surface) is prevented. Two slide plates 95 are provided on each surface (four surfaces) at positions facing the slide plate 90 provided on the inner cylinder 18b in the expansion / contraction direction of the expansion / contraction rod 18. In FIG. 8B, reference numeral 99 denotes a slide plate provided on the outer surface of the rod side end of the tube 17a of the telescopic cylinder 17, which contacts the inner surface of the inner cylinder 18b and slides the inner cylinder 18b.

  In the telescopic rod 18, when the telescopic cylinder 17 is extended from the contracted state of FIGS. 5 and 6, the slide plate 90 of the inner cylinder 18 b slides on the inner surface of the outer cylinder 18 a and the lower end of the tube 17 a of the telescopic cylinder 17. The inner cylinder 18b slides on the slide plate 99, and the inner cylinder 18b descends while the outer surface of the inner cylinder 18b slides on the slide plate 95 provided on the outer cylinder 18a, as shown in FIGS. It reaches an extended state. When the inner cylinder 18b is lowered, the hose guide 78 is lowered while sliding in the guide frame 81 provided on the outer cylinder 18a.

  When the telescopic cylinder 17 extends to the stroke end, as shown in FIG. 11, the slide plate 90 provided on the outer surface of the inner cylinder 18b comes close to the slide plate 95 provided on the inner surface of the outer cylinder 18a and expands and contracts. It faces the direction of expansion and contraction of the rod 18. For this reason, even if the telescopic cylinder 17 is broken, the slide plate 90 and the stopper 91 act as a locking member that comes into contact with the stopper 98 of the slide plate 95, so that the inner cylinder 18b or the bucket 16 is prevented from falling. .

  Next, an example of a hydraulic circuit of a deep excavator using the telescopic rod 18 will be described with reference to FIG. 12, 47 is a main hydraulic pump included in the hydraulic power unit 4 mounted on the swing frame 3a of the ground excavator main body shown in FIGS. 1 and 2, and 48 is a pilot hydraulic pump. Reference numeral 50 denotes a control valve that opens and closes the bucket 16. In this embodiment, the control valve 50 is also used for expansion and contraction of the expansion cylinder 17. Reference numeral 51 denotes a pilot valve for operating the control valve 50. The pilot valve 51 has an operation lever 51a, and a switch 51b having a function described later is attached to the operation lever 51a.

  Reference numeral 53 denotes a first pipe connected to one secondary port A of the control valve 50, and reference numeral 54 denotes a second pipe connected to the other secondary port B. The first pipeline 53 branches into a pipeline 53A and a pipeline 53B. The pipe line 53A is an open side pipe line connected to the open side chamber 36d (see FIG. 4) of the bucket cylinder 36. The pipe line 53B is an extension side pipe line connected to the bottom chamber 17c of the telescopic cylinder 17.

  The second pipeline 54 branches into a pipeline 54A and a pipeline 54B. The pipe line 54 </ b> A is a closed side pipe line connected to the closed side chamber 36 e of the bucket cylinder 36. Reference numeral 54 </ b> B denotes a contraction side pipe line connected to the rod chamber 17 d of the telescopic cylinder 17. 56 and 57 are overload relief valves for setting the maximum hydraulic pressures of the first pipe line 53 and the second pipe line 54, respectively, and the operating pressure thereof is, for example, 35 MPa.

  58A is a sequence valve provided in the extension side pipe 53B of the telescopic cylinder 17, and 59A is a check valve provided in parallel to the sequence valve 58A. This sequence valve 58A switches the control valve 50 to the right position so that hydraulic fluid is supplied to the open side chamber 36d of the bucket cylinder 36 of the bucket 16 and the bottom chamber 17c of the telescopic cylinder 17 via the first conduit 53. When supplied simultaneously, the bucket 16 is opened first.

  58B is a sequence valve provided in the contraction side pipe 54B of the telescopic cylinder 17, and 59B is a check valve provided in parallel to the sequence valve 58B. The sequence valve 58B operates the switching operation of the control valve 50 to the left position so that hydraulic oil is supplied to the closing side chamber 36e of the bucket cylinder 36 of the bucket 16 and the rod chamber 17d of the expansion / contraction cylinder 17 via the second conduit 54. When supplied simultaneously, the closing of the bucket 16 is preceded.

  Reference numeral 60 denotes a bypass pipe connecting the bottom chamber 17c and the rod chamber 17d of the expansion cylinder 17, and 58C1 and 58C2 are sequence valves connected in series to the bypass pipe 60. In addition, the hydraulic oil in the rod chamber 17d is returned to the bottom chamber 17c. 59C1 and 59C2 are check valves provided in parallel to the sequence valves 58C1 and 58C2, respectively. A check valve 62 is provided between the rod chamber 17d of the expansion cylinder 17 and the sequence valve 58B. When the expansion cylinder 17 is extended, the hydraulic oil from the rod chamber 17d is returned only to the bottom chamber 17c side. Is for.

  61 is a pilot line for the sequence valves 58C1 and 58C2, and this pilot line 61 is provided between the sequence valve 58B and the check valve 62 in the contraction side line 54B of the expansion cylinder 17 and for the pilots of the sequence valves 58C1 and 58C2. Connect between rooms. This pilot line 61 secures the hydraulic oil pressure to be applied to the rod chamber 17d by increasing the operating pressure of the recirculation sequence valves 58C1 and 58C2 when the expansion cylinder 17 is contracted. Provided for contraction.

  A pilot check valve 65 is provided between the sequence valve 58A and the bottom chamber 17c of the expansion / contraction cylinder 17 in the expansion side pipe 53B of the expansion / contraction cylinder 17. Reference numeral 66 denotes a pilot pipe line of the pilot check valve 65. The pilot pipe line 66 uses the hydraulic pressure between the sequence valve 58B and the check valve 62 provided in the contraction side pipe 54B of the expansion cylinder 17 as a pilot pressure. In addition to the pilot chamber of the pilot check valve 65, the flow of hydraulic oil in the reverse direction in the pilot check valve 65 is allowed when there is hydraulic pressure in the pilot line.

  Reference numeral 70 denotes a stop valve, 71 denotes a maximum opening pressure bucket relief valve connected in series to the stop valve 70, and 72 denotes a check valve connected in parallel to the bucket relief valve 71. These valves 70 to 72 are provided between the secondary port 53 on the bucket opening side of the control valve 50 and the oil tank 73. The operating pressure of the bucket relief valve 71 is set lower (for example, 20 MPa) than the operating pressure (for example, 25 MPa) of the sequence valve 58A. The operating pressure of the sequence valve 58B provided in the contraction side pipe 54B of the telescopic cylinder 17 is set to a value that is the same as or close to that of the sequence valve 58A.

  74 is a pilot valve of the stop valve 70, and this pilot valve 74 is provided between the bucket opening side secondary pipe 75 of the pilot valve 51 of the control valve 50 and the oil tank 73. The pilot valve 74 is of an electromagnetic operation type. When a switch 51b attached to the operation lever 51 of the pilot valve 51 of the control valve 50 is turned on, the solenoid 74a is energized and switched from the left position to the right position in the figure. Is.

  When excavating with this deep excavator, if the operation lever 51a shown in FIG. 6 is operated in the direction of the arrow 76, pilot pressure oil from the pilot hydraulic pump 48 is supplied to the pilot line 75 and the control valve 50 is operated. To the right position. As a result, the hydraulic oil discharged from the main hydraulic pump 47 is supplied to the first pipeline 53, and is first supplied to the open side chamber 36d of the bucket cylinder 36 via the pipeline 53A. 41 and 41 rotate upward as indicated by a two-dot chain line around the pins 42 and 42, and the bucket 16 opens.

  Here, if the operator does not turn on the switch 51b, the stop valve 70 is in the illustrated cutoff position, and the bucket relief valve 71 is cut off from the circuit, so that the bucket relief valve 71 does not act.

  In this state, the operation pressure is set so that the sequence valve 58A provided in the pipe line 53B on the extension side of the telescopic cylinder 17 does not open at the hydraulic pressure required when the bucket 16 is opened. During the opening operation, the sequence valve 58A is not opened and the telescopic cylinder 17 is not extended. When the bucket 16 is opened to the maximum opening, the sequence valve 58A is opened due to the increase in the hydraulic pressure of the first pipe 53, and the telescopic cylinder 17 is extended. For this reason, when excavating a deep portion of the vertical hole 7 shown in FIG. 1, the telescopic cylinder 17 extends with the bucket 16 open. As described above, the telescopic core 17 is extended with the telescopic cylinder 17 extended, or the telescopic cylinder 17 is extended with the telescopic core 10 extended to the maximum, so that the bucket 16 is placed at the bottom of the vertical hole 7. Can be pressed.

  Here, while the telescopic rod 18 is contracted together with the telescopic cylinder 17 as shown in FIGS. 5 and 6, the hydraulic pressure provided at the lower end of the inner cylinder 18b during the stretched state as shown in FIGS. Since the pipe connector 77 is lowered, the hose guide 78 is lowered in a state where the hose guide 78 is prevented from bulging outward while sliding on the guide frame 81. Along with this, the U-shaped curved portion 78a (see FIG. 9A) of the hose guide 78 is also lowered.

  Next, when the operator in the cab 5 operates the pilot valve 51 to switch the control valve 50 to the left position, the hydraulic oil discharged from the main hydraulic pump 47 is supplied to the second conduit 54. Here, in normal excavation, the operating pressure of the sequence valve 58B is set so as not to open at the hydraulic pressure required when closing the bucket 16, so the sequence valve 58B is not opened, and the telescopic cylinder 17 is Does not shrink. For this reason, from the bucket open state where the tube 36c of the bucket cylinder 36 is raised, the tube 36c is lowered, the shells 41 and 41 are rotated downward about the pins 42 and 42, the bucket 16 is closed and excavation is performed. .

  When the bucket 16 is closed, the sequence valve 58B is opened due to the increase in the hydraulic pressure of the second pipe 54, and accordingly, the pilot check valve 65 is also opened due to the increase in the hydraulic pressure of the pilot pipe 66, and at the same time, the sequence valve 58C1. , The pilot pressure is applied to the pilot chamber of 58C2 from the pilot line 61, the operating pressure of the sequence valves 58C1 and 58C2 increases, the flow of hydraulic oil through the sequence valves 58C1 and 58C2 is blocked, and the hydraulic oil is introduced into the rod chamber 17d. Then, the hydraulic oil in the bottom chamber 17c flows out to the oil tank 73 through the pilot check valve 65, and the telescopic cylinder 17 contracts.

  Thus, when the earth and sand are accommodated in the bucket 16 and the telescopic cylinder 17 is in a contracted state, the control valve 50 is returned to the neutral position, the telescore 10 is contracted, and the transport is performed as shown in FIG. By placing the bucket 16 on the loading platform 63 of the commercial vehicle and switching the control valve 50 to the left position again, the bucket 16 can be opened while the telescopic cylinder 17 is closed, and the earth and sand in the bucket 16 can be loaded on the loading platform 63. it can.

  On the other hand, when the operator turns on the switch 51b when the bucket is opened, the solenoid 74a of the pilot valve 74 of the stop valve 70 is energized from a power source (not shown), and the pilot valve 74 is switched to the right position. For this reason, the pilot pressure oil in the bucket opening side pilot pipeline 75 of the pilot valve 51 is supplied to the operation chamber of the stop valve 70 through the pilot valve 74, so that the stop valve 70 is switched to the right communication position, and the bucket relief valve 71 is put into the circuit.

  In this state where the stop valve 70 is switched to the communication side, when the bucket 16 is in the most open state, the hydraulic pressure of the first conduit 53 increases. However, the bucket relief valve 71 causes the bucket relief valve 71 to act. The hydraulic pressure in the first pipe line 53 does not increase above the operating pressure set by the valve 71. Here, since the operating pressure of the bucket relief valve 71 is set lower than the operating pressure of the sequence valve 58A, the sequence valve 58A does not open and the telescopic cylinder 17 does not expand.

  As shown in FIG. 3, the telescopic rod 18 of the present embodiment has a bottom end of the telescopic cylinder 17 built in the telescopic rod 18 connected to the upper bracket 20 of the telescopic rod 18 by a pin 23, and the end of the rod. The upper bracket 20 and the lower bracket 21 are originally provided for connection and have high strength. The upper bracket 20 and the lower bracket 21 are originally connected for connection to the lower bracket 21 which is an open / close bucket connecting portion of the telescopic rod 18. Therefore, the connecting portion of the telescopic cylinder can be configured with a simple structure without requiring a complicated structure such as welding of a reinforcing member or the like for connecting the telescopic cylinder 17.

  Further, since the telescopic cylinder 17 is protected by the telescopic rod 18, damage to the telescopic cylinder 17 is prevented.

  In addition, since both ends of the telescopic cylinder 17 are connected to the upper and lower brackets 20 and 21 of the telescopic rod 18, the telescopic rod 18 can have a large telescopic stroke. For this reason, when the same telescopic rod 18 is used, excavation at a deeper location is possible.

  In the present embodiment, since the cross-sectional shapes of the outer cylinder 18a and the inner cylinder 18b are rectangular, the inner cylinder is not twisted with respect to the outer cylinder as in the case of a circle. For this reason, excessive force does not act on the hydraulic hose attached to the telescopic rod 18 due to the kinking of the telescopic rod 18, and damage to the hydraulic hose is prevented. Further, as shown in FIG. 7 (B), by connecting a connector 31 provided on the outer periphery of the tube to be connected to the rod chamber 17d of the telescopic cylinder 17 at the corner portion of the inner cylinder 18b, the outer cylinder 18a, The inner cylinder 18b can be made smaller than when it is circular. In addition, since the direction of the connecting portions 20b and 21b of the upper and lower brackets 20 and 21 is made to intersect, the bucket 16 and the telescopic rod 18 can be swung by an external force acting on the bucket 16, Excessive force is prevented from being applied to the telescopic rod 18 and these damages are prevented.

  In the present embodiment, a stopper 98 that prevents the inner cylinder 18b from coming off is provided on the inner surface of the lower end portion of the outer cylinder 18a. The stopper 98 is placed on the outer surface of the upper end portion of the inner cylinder 18b when the telescopic cylinder 17 is broken. Since the locking member (slide plate 90 or the like) that contacts and prevents the inner cylinder from coming off is provided, even if the telescopic cylinder 17 breaks, the inner cylinder 18b does not come off from the outer cylinder 18a, and the bucket 16 falls. As a result, safety is improved.

  Further, in the present embodiment, a block 25 to which a hydraulic hose extended from the telescoreme 10 side is detachably connected is provided at the upper portion of the outer cylinder 18a, and the oil to the telescopic cylinder 17 is provided in this block 25. Sequence valves 58A, 58B, 58C1, and 58C2 for setting the operation order of the branch path and the bucket 16 and the telescopic cylinder 17 branching to the oil path to the path and the bucket 16 are provided. With such a structure, when the telescopic rod 18 is newly attached to the existing telescoreme 10, it is possible to connect the hydraulic hose attached to the telescoreme 10 in advance to the block 25 as it is. The existing hydraulic hose can be used as it is, and application to the existing telescore 10 becomes easy.

  Further, when the telescopic rod of the present embodiment is applied to a deep excavator having the telescoreme 10, the telescopic cylinder 17 can be extended for excavation, so that deeper excavation is possible. On the other hand, when the soil is discharged, the telescopic cylinder 17 can be discharged short, so that the bucket 16 can be discharged without being held by the loading platform 63 or the earth and sand 64 on the loading platform 63. That is, as compared with the conventional suspension bracket, the restriction on the bucket height in the soil removal is relaxed, and excavation can be performed at a deeper location.

  Moreover, since the hydraulic lines 53 and 54 for operating the telescopic cylinder 17 and the control valve 50 are also used for the bucket 16, the hydraulic pressure attached to the telescore 10 of the existing deep excavator. Since the hose and the control valve 50 can also be used as they are, they can be implemented by a slight modification of an existing deep excavator and can be provided at low cost.

  In the hydraulic circuit of FIG. 12, a bucket relief valve 71 and a stop valve 70 are provided between the first pipeline 53 that is the bucket opening side pipeline of the control valve 50 and the oil tank 73, and the soil is discharged. In this case, if the switch 51b is turned on in advance and the stop valve 70 is operated to the communication side, the first pipe line 53 of the control valve 50 does not exceed the operating pressure of the bucket relief valve 71. For this reason, since the extension of the telescopic cylinder 17 after the opening of the bucket 16 is prohibited, there is no possibility of the bucket 16 colliding with the loading platform 63 (see FIG. 2) due to the extension of the telescopic cylinder 17, and the burden on the operator in the soil removal is reduced. This can be reduced, improving operability and improving safety. Such a stop valve 70 or bucket relief valve 71 may be provided between the other secondary port B of the control valve 50 and the oil tank 73, and can be stopped by turning on the switch 51b. The circuit may be configured so that the valve 70 is in the shut-off position and the bucket relief valve 71 does not act.

  The bucket to which the telescopic rod 18 of the present invention is applied is not the structure shown in FIG. 4 but a hydraulic cylinder for opening and closing is attached between the fixed rod 36b suspended from the telescopic rod 18 and the shell 41. It can also be used. Further, the present invention can be applied not to excavation buckets but to other openable buckets such as grapple buckets for cargo handling.

  Further, as shown in FIG. 13, the telescopic rod of the present invention can be used for deep excavation, cargo handling, etc. even when it is attached to the arm 10 </ b> X of a general-purpose hydraulic excavator instead of the telescore 10. The present invention is not limited to the above-described embodiment, and various changes and additions can be made without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 1: Lower traveling body, 2: Turning apparatus, 3: Upper turning body, 3a: Turning frame, 4: Hydraulic power unit, 5: Cab, 6: Counterweight, 7: Vertical hole, 8: Boom, 9: Boom cylinder, 10 : Telescore: 10a: outer arm, 10b: center arm, 10c: inner arm, 14: arm cylinder, 16: clamshell bucket, 17: telescopic cylinder, 17a: tube, 17b: rod, 18: telescopic rod, 18a: outside Tube, 18b: Inner tube, 19, 22, 23, 24: Pin, 20: Upper bracket, 20a: End plate, 20b: Connection portion, 20e: Opening portion, 21: Lower bracket, 21a: End plate, 21b: Connection Part, 21e: opening, 25: block, 26, 27: hydraulic hose, 30: hydraulic piping, 32a, 32b: hydraulic hose, 36: bucket Linda, 36a: piston, 36b: rod, 36c: tube, 36d: open side chamber, 36e: closed side chamber, 40: frame, 41: shell, 43: connecting arm, 47: main hydraulic pump, 48: pilot hydraulic pump, 50 : Control valve, 51: pilot valve, 53: first pipeline, 53A: open side pipeline, 53B: extension side pipeline, 54: second pipeline, 54A: closed side pipeline, 54B: contraction side Pipeline, 58A, 58B, 58C1, 58C2: sequence valve, 59A, 59B, 59C1, 59C2: check valve, 60: bypass pipeline, 61: pilot pipeline, 62: check valve, 63: transport vehicle Loading platform, 64: earth and sand, 65: pilot check valve, 66: pilot pipeline, 70: stop valve, 71: bucket relief valve, 78: hose guide, 79a, 79b: oil Hose, 80, 81: guide frame, 83: cover, 84 to 87: protective frame, 88, 89: bucket connection piping, 90: slide plate (locking member), 91: stopper, 95: slide plate, 98: Stopper

Claims (5)

A telescopic rod that is attached to the arm of a self-propelled working machine, has an openable bucket attached to the lower end, fits the outer cylinder and the inner cylinder so that they can be expanded and contracted, and houses the expansion cylinder inside In
The expansion / contraction direction of the telescopic rod to an upper bracket provided at the upper end of the outer cylinder and connected to the arm by a pin, and a lower bracket provided to the lower end of the inner cylinder and connected to the openable bucket by a pin, respectively An opening that penetrates the
One end of the telescopic cylinder is inserted into the opening provided in the upper bracket and connected to the upper bracket by a pin,
The telescopic rod, wherein the other end of the telescopic cylinder is inserted into the opening provided in the lower bracket and connected to the lower bracket by a pin. The telescopic rod according to claim 1,
The outer cylinder and the inner cylinder are rectangular in cross section,
The outer cylinder and the inner cylinder are rectangular in cross section,
The telescopic rod, wherein the direction of the pin hole of the upper bracket connected to the arm is orthogonal to the direction of the pin hole of the lower bracket connected to the openable bucket. The telescopic rod according to claim 1 or 2,
A stopper is provided on the inner surface of the lower end of the outer cylinder to prevent the inner cylinder from coming off,
A telescopic rod, wherein a locking member is provided on the outer surface of the upper end portion of the inner cylinder so as to contact the stopper and prevent the inner cylinder from coming off. The telescopic rod according to any one of claims 1 to 3,
A block to which a hydraulic hose extending from the arm side is detachably connected to an upper portion of the outer cylinder is provided,
In the block, there is provided a branch path that branches into an oil path to the telescopic cylinder and an oil path to the open / close type bucket, and in the block, the open / close operation of the open / close type bucket is expanded and contracted by the telescopic cylinder. A telescopic rod characterized by providing a sequence valve to be performed in advance. A deep excavator, wherein the telescopic rod according to any one of claims 1 to 4 is attached to a tip of a telescore as the arm.

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