JP4891291B2 - Excavator - Google Patents

Description

  The present invention relates to a tunneling machine that digs a tunnel, and more particularly to a tunneling machine that can be pulled back to a start shaft.

  Some excavators can be pulled back to the starter shaft for repair and cleaning, or to change the cutter head according to the bedrock and soil quality. Conventionally, such an excavator as shown in FIG. 8 and FIG. 9 has been disclosed by the applicant (see Patent Document 1 below). Next, this excavator will be described.

  The excavator 30 is positioned in the outer cylinder 3 detachably fixed in front of a buried pipe (not shown), positioned by a spacer 3f, fixed by a coupling pin 3e, and tunneled by a cutter head 40 attached to the front end thereof. It is something to dig up.

  The outer cylinder 3 includes a front casing 3a and a rear casing 3c, and has a sealing structure in which a connecting portion 3d of both casings can be bent.

  The excavator 30 is also separated into a front cylinder 30a and a rear cylinder 30b at the position of the connecting part 3d between the front casing 3a and the rear casing 3c of the outer cylinder 3, and a connecting part between the front cylinder 30a and the rear cylinder 30b. 33 is made to be bendable and has a sealing structure. A jack 31 is stretched between the front barrel 30a and the rear barrel 30b. By extending and contracting the jack 31, the excavator 30 and the outer cylinder 3 can be bent at the same portion.

  The cutter head 40 is driven by a drive motor 32 installed in the excavator 30. For this reason, the drive shaft 36 splined to the output shaft 34 of the drive motor 32 is connected to the boss 42 of the cutter head 40.

  The cutter head 40 includes a boss 42, a plurality of arms 50 standing radially from the boss 42, a lever 56 pivotally supported by a pin 54 on the arm 50, an overbit 46 attached to the tip of the lever 56, an arm The rotating plate 44 is fixed to the front edge of the 50, and the inner bits 48 and 48a are attached at appropriate positions on the rotating plate 44 so that excavation can be made without leaving a portion where the overbit 46 leaks excavation. The over bit 46 is movable in the radial direction by the swing of the lever 56. Each arm 50 reinforces the arm 50 by connecting a pair of support plates 50a that are pivotally supported by pins 54 with the lever 56 interposed therebetween, and the support plates 50a, and restricts the rotation of the lever 56 to the rear. Arm side thrust receiver 50b. At least one 48a of the inner bit 48 is also adjustable in the radial direction so as not to cause excavation leakage.

  Further, scrapers 58 are disposed on both sides of the overbit 46 at the front end of the lever 56 to protect the overbit 46. Further, the rotating plate 44 is provided with a window 44b for allowing the excavated earth and sand to pass rearward. The over bit 46 and the inner bits 48 and 48a can be changed to other appropriate cutter bits.

  A rod 60 passes through the drive shaft 36 and the drive motor 32 so as to be movable back and forth. The rear end of the rod 60 is connected to a connecting rod 64 that connects the output portions of a pair of actuators 62 fixed to the rear portion of the drive motor 32 through a thrust bearing 65 so as to allow the rod 60 to rotate around its axis. ing. For this reason, the rod 60 can be rotated together with the cutter head 40. The front end of the rod 60 is engaged with a recess at the inner end of the lever 56 via a transmission member 66 arranged in the space 52.

  When the actuator 62 is actuated to move the rod 60 forward, the transmission member 66 also moves forward, the lever 56 rotates outward, and the outer end of the overbit 46 is larger than the outer diameter of the outer cylinder 3. It is located outside, the outer diameter of the cutter head 40 is increased, and the tunnel can be dug while securing an appropriate amount of extra excavation. At this time, the lever 56 swings outward as much as possible, the flat portion of the inner end contacts the boss 42, and the rear edge contacts the arm-side thrust receiver 50b.

  On the other hand, when the actuator 62 is actuated to move the rod 60 rearward, the lever 56 rotates inward, the outer end of the overbit 46 is positioned inside the inner diameter of the outer cylinder 3, and the cutter head 40. The outer diameter of becomes smaller. Therefore, when the coupling pin 3e that connects the outer cylinder 3 and the excavator 30 is removed, the excavator 30 moves backward in the outer cylinder 3 and a buried pipe (not shown) to the start shaft side by pulling backward. Can be pulled back.

  Further, in this excavator 30, an eccentric shaft portion 36a is formed on the drive shaft 36 near the front end of the front barrel 30a, and a truncated cone-shaped cone rotor 70 is inserted into the eccentric shaft portion 36a with a bearing (not shown). Mounted freely. When the drive shaft 36 rotates, the cone rotor 70 rotates around the drive shaft 36 while performing an eccentric motion. A large number of protrusions 70 a are provided on the outer peripheral surface of the cone rotor 70. An outer cone 74 is disposed around the cone rotor 70, and a protrusion 74 a is also disposed on the inner peripheral surface of the outer cone 74.

  A crushing chamber 76 that is narrower toward the rear side is formed by the cone rotor 70 and the outer cone 74. A stirring blade 82 is attached to the arm 50 of the cutter head 40 installed in front of the crushing chamber 76. The outer peripheral surface of the boss 42 of the cutter head 40 and the outer peripheral surface of the cone rotor 70 are continuous. The crushing chamber 76 is connected to a mud pipe 78 for discharging mud water in order to facilitate the agitation and sending of mud, and the crushing chamber 76 is made fine at the rear end of the crushing chamber 76. In addition, a mud discharge pipe 80 for transferring the earth and sand mixed with muddy water to the rear is connected. Seal members 84 for preventing intrusion of muddy water are disposed at the front end and the rear end of the cone rotor 70.

The earth and sand excavated by the rotation of the cutter head 40 passes through the peripheral portion 44a and the window 44b of the rotating plate 44, and smoothly flows into the crushing chamber 76 while being mixed and stirred with the muddy water by the stirring blades 82. The earth and sand that has entered the crushing chamber 76 collides with the cone rotor 70 that rotates eccentrically and is crushed more finely. Since the cone rotor 70 rotates freely, only a specific portion is not worn or damaged, and the drive motor 32 is overloaded even if a hard and large rock or the like enters the crushing chamber 76. The rock can be crushed over time. Thus, the excavator 30 can excavate the tunnel efficiently.
JP-A-2005-299113

  The excavator 30 can move the buried pipe backward by moving the outer diameter of the cutter head 40 and pull it back to the start shaft, but the outer diameter of the cutter head 40, such as the actuator 62, the rod 60, the transmission member 66, etc. Therefore, there is a problem that the excavator 30 becomes large and expensive.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a small-sized and low-priced excavator while allowing the buried pipe to be moved backward and pulled back to the start shaft.

In order to solve the above-described problem, the invention according to claim 1 includes a cutter head having a lever having a cutter bit attached to the tip, an arm that pivotally supports the lever, and a boss to which the arm is fixed. In addition, in the excavator in which the arm is provided with an arm-side thrust receiver that restricts rotation of the lever to the rear, the lever is in contact with the thrust receiver in a state in which the lever is in contact with the thrust receiver The lever and the arm are clamped by a clamp bolt that penetrates an arc-shaped slit that allows the lever to rotate forward provided in a contact portion between the bolt hole provided in the arm and the thrust receiver of the lever. It is characterized by having concluded.

  The invention according to claim 2 includes a cutter head having a lever having a cutter bit attached to the tip, an arm that pivotally supports the lever, and a boss to which the arm is fixed, and the lever is mounted on the lever. In an excavator provided with an arm-side thrust receiver that restricts rearward rotation of the lever, the lever and the thrust receiver are disconnected when a predetermined force is applied while the lever is in contact with the thrust receiver. It is characterized by being fastened with a clamp bolt.

According to the first aspect of the present invention, the cutter head includes a lever having a cutter bit attached to the tip, an arm that pivotally supports the lever, and a boss to which the arm is fixed. In an excavator provided with an arm-side thrust receiver that restricts rotation of the lever to the rear, the bolt hole provided in the arm and the thrust receiver of the lever in a state where the lever is in contact with the thrust receiver. Since the lever and the arm are fastened by a clamp bolt that passes through an arc-shaped slit that allows the lever to rotate forward provided in the contact portion , the excavator is pulled backward with a hydraulic jack or the like. When the outer cylinder and the buried pipe are moved backward, the lever comes into contact with the outer cylinder and tries to rotate inward. Since the lever and the arm are fastened by the clamp bolt that passes through the arc-shaped slit that allows the lever to rotate forward, provided in the contact portion between the bolt hole provided in the arm and the thrust receiving of the lever , the clamp bolt As a result of relative movement in the slit, the lever rotates inwardly against the frictional force between the arm and the lever caused by tightening the clamp bolt, and the outer diameter of the cutter head is reduced. Now that the excavator can be moved backward in the buried pipe and pulled back to the start vertical shaft side, parts for changing the outer diameter of the cutter head, such as actuators and transmission members, are no longer necessary. An excavator with low cost and few breakdowns can be obtained. Even if rock debris is caught between the lever and the arm or between the lever and the boss, if the excavator is pulled backward with a hydraulic jack or the like with a strong force, the lever hits the outer cylinder. Since it can be rotated inward and contacted, rock fragments and the like can be easily crushed and the outer diameter of the cutter head can be reliably reduced, so failure can be further reduced.

  According to the second aspect of the present invention, the cutter head includes a lever having a cutter bit attached to the tip, an arm that pivotally supports the lever, and a boss to which the arm is fixed. In an excavator provided with an arm-side thrust receiver that restricts rearward rotation of the lever, the lever and the thrust receiver are cut when a predetermined force is applied while the lever is in contact with the thrust receiver. When the excavator is pulled backward with a hydraulic jack or the like to move backward in the outer cylinder and the buried pipe, the lever comes into contact with the outer cylinder and rotates inward, causing the clamp bolt to cut. Is done. As a result, the lever rotates inward, and the outer diameter of the cutter head is reduced. For this reason, this invention also has the same effect as the invention which concerns on Claim 1.

  Hereinafter, based on FIG.1 and FIG.2, 1st Example which concerns on the excavation machine of this invention is described. FIG. 1 is a longitudinal sectional view of the vicinity of the cutter head when the outer diameter of the cutter head of this excavator is enlarged. FIG. 2 is a longitudinal sectional view of the vicinity of the cutter head when the outer diameter of the cutter head of this excavator is reduced. FIG. 3A is an enlarged view of a portion A in FIG. FIG. 3B is a cross-sectional view taken along the line BB in FIG. FIG. 4A is an enlarged view of a portion A in FIG. FIG. 4B is a cross-sectional view taken along the line CC of FIG.

  The excavator 30A is substantially the same as the conventional excavator 30 described above, and includes a lever 56 with an overbit 46 attached to the front end, an arm 50 that pivotally supports the lever 56 with a pin 54, and the arm 50 fixed thereto. A cutter head 40 having a boss 42 is provided. The arm 50 includes a pair of support plates 50a and an arm-side thrust receiver 50b that connects and reinforces the pair of support plates 50a and restricts the rotation of the lever 56 rearward.

  However, in this excavator 30A, the arm-side thrust receiver 50b is provided on the rear edge side of the support plate 50a, and the protrusion 56b that contacts the arm-side thrust receiver 50b is provided on the rear edge of the lever 56. The protrusions 56b are provided with different thicknesses on both sides of the lever 56 in the thickness direction. One support plate 50a is provided with a pair of bolt holes 50d, the thin protrusion 56b is provided with a pair of slits 56a, and the pair of clamp bolts 50c are respectively passed through the bolt holes 50d and the slits 56a. The lever 56 and the arm 50 are fastened in a state where the protruding portion 56b is in contact with the arm-side thrust receiver 50b. Here, the pair of slits 56a extend in an arc shape around the pin 54 so that the lever 56 can rotate around the pin 54, and are opened at the rear edge of the protruding portion 56b.

  One or three or more clamp bolts 50c and slits 56a may be provided, but it is appropriate to provide a pair of clamp bolts 50 in consideration of the strength of the protrusions 56b in order to obtain a desired clamping force. Further, the slit 56a may be a straight line as long as it is open at the rear edge of the protrusion 56b because the protrusion 56b is somewhat deformed. Furthermore, when the slit 56a extends long in an arc shape centered on the pin 54, the slit 56a does not necessarily need to be opened at the rear edge of the protruding portion 56b.

  In addition, a lever side thrust receiver 56c is also provided in the vicinity of the inner end of the rear edge of the lever 56. When the protruding portion 56b contacts the arm side thrust receiver 50b, the lever side thrust receiver 56c contacts the boss 42. It also comes in contact.

  Initially, as shown in FIG. 1, the excavator 30A is in a state in which the protruding portion 56b of the lever 56 is in contact with the arm-side thrust receiver 50b, that is, in a state where the lever 56 is rotated most outward. Since it is fixed to the arm 50 by 50c, the tunnel can be dug as it is.

  When the excavator 30A is pulled backward by a hydraulic jack or the like to return the outer cylinder 3 and a buried pipe (not shown) to the start shaft side to repair the excavator 30A, the lever 56 comes into contact with the outer cylinder 3 Try to rotate towards. At this time, when the clamp bolt 50c relatively moves in the slit 56a, the lever 56 rotates inwardly against the frictional force between the arm 50 and the lever 56 by tightening the clamp bolt 50c. Then, the clamp bolt 50c moves relatively in the slit 56a toward the opening side of the slit 56a, and finally comes off the slit 56a. Thus, the lever 56 freely rotates inward, and the outer diameter of the cutter head 40 is reduced. Thus, the outer diameter of the cutter head 40 becomes smaller than the inner diameter of the outer cylinder 3 and the buried pipe, and the excavator 30A can be pulled back to the start shaft side. At this time, even when rock fragments or the like are bitten between the lever 56 and the arm 50 or between the lever 56 and the boss 42, the excavator 30A is pulled backward with a hydraulic jack or the like with a strong force. Since the lever 56 is in contact with the outer cylinder 3 and is rotated inward, rock fragments and the like can be easily crushed, so that the outer diameter of the cutter head 40 can be reliably reduced.

  Therefore, according to the present embodiment, in order to reduce the outer diameter of the cutter head 40, parts such as an actuator, a rod, and a transmission member are not required as in the conventional case, and the excavator 30A is pulled backward with a strong force. By doing so, since the outer diameter of the cutter head 40 can be reliably reduced, an inexpensive, small and less troubled excavator can be realized. In the present embodiment, a pair of protrusions 56b that contact the arm-side thrust receiver 50b are provided at the rear edge of the lever 56, and the slits 56a are formed in the protrusions 56b. Is easy. Furthermore, since the slit 56a is provided in the thin protrusion 56b of the two protrusions 56b, the slit 56a can be easily formed.

  Next, based on FIGS. 5-7, 2nd Example which concerns on the excavation machine of this invention is described. (A) of FIG. 5 is a figure explaining the state which expanded the outer diameter of the cutter head of this excavator. FIG. 5B is a cross-sectional view taken along the line DD in FIG. FIG. 6A is a diagram for explaining a state in which the outer diameter of the cutter head of this excavator is reduced. FIG. 6B is a cross-sectional view taken along line EE in FIG. FIG. 7 is a diagram illustrating a clamp bolt.

  In this excavator 30B, the arm-side thrust receiver 50b connecting the pair of support plates 50a and the protrusion 56d provided at the rear edge of the lever 56 are brought into contact with each other, so that the arm-side thrust receiver 50b and the protrusion 56d However, they are connected by a clamp bolt 50g which is cut when a tensile force of a predetermined level or more is applied. In order to pass the clamp bolt 50g, the arm-side thrust receiver 50b and the protruding portion 56d are provided with through holes 50e and 56e, and the protruding portion 56d is provided with a space 56f in which a nut can be placed and removed. ing. Further, as shown in FIG. 7, a breaking groove 50h that makes one round in the circumferential direction is formed in the clamp bolt 50g so as to be surely cut at a predetermined position when receiving a tensile force of a predetermined value or more. . Other than this, the second embodiment is the same as the first embodiment.

  According to the present embodiment, when the excavator 30B is pulled backward by a hydraulic jack or the like and pulled back to the start shaft side, the lever 56 comes into contact with the outer cylinder 3 and tries to rotate inward. At this time, the clamp bolt 50g is cut by receiving a predetermined tensile force or more. Thus, the cutter head 40 has an outer diameter smaller than the inner diameter of the outer cylinder 3 and the buried pipe, and can pull the excavator 30B back to the start shaft side. Thus, the present embodiment has the same effect as the first embodiment.

  By the way, the present invention is not limited to the above embodiment, and various modifications are possible. For example, in both the above-described embodiments, the protrusions 56b and 56d are provided at the rear edge of the lever 56, but the protrusions 56b and 56d are not provided, and the rear edge of the lever 56 is brought into direct contact with the arm-side thrust receiver 50b. The lever 56 and the arm 50 may be fixed. In this case, in the first embodiment, the slit 56a is provided at the rear edge of the lever 56, and the clamp bolt 50c is passed through the pair of support plates 50a and the slit 56a so that the lever 56 and the arm 50 To fix. In the second embodiment, the lever 56 and the arm 50 are fastened with the clamp bolt 50g that is cut when a shearing force of a predetermined level or more is applied through the lever 56 and the arm 50. In this case, a pair of cutting grooves 50h is provided in the clamp bolt 50g so that the clamp bolt 50g after cutting does not hinder the rotation of the lever 56, and the pair of cutting grooves 50h are respectively connected to the pair of support plates 50a and the lever. 56 must be located at the boundary with 56.

It is a longitudinal cross-sectional view when the outer diameter of the cutter head of the excavation machine according to the first embodiment of the present invention is enlarged. It is a longitudinal cross-sectional view when the outer diameter of the cutter head of the excavator is reduced. It is an enlarged view of A part in FIG. FIG. 3 is an enlarged view of a portion A in FIG. 2. It is a figure explaining the state which expanded the outer diameter of the cutter head of the excavation machine which concerns on 2nd Example of this invention. It is a figure explaining the state which reduced the outer diameter of the cutter head of the excavation machine which concerns on 2nd Example of this invention. It is a figure explaining the clamp bolt used for the excavation machine which concerns on 2nd Example of this invention. It is a longitudinal cross-sectional view of the conventional excavation machine. It is a front view of the conventional excavation machine.

Explanation of symbols

30A, 30B Excavator 40 Cutter head 42 Boss 46 Over bit (cutter bit)
50 Arm 50b Thrust receiving arm 50c, 50g Clamp bolt 56 Lever 56a Slit 56b Projection

Claims (2)

A cutter head having a lever with a cutter bit attached to the tip, an arm that pivotally supports the lever, and a boss to which the arm is fixed is provided, and the rearward rotation of the lever is limited to the arm. In the excavator with arm side thrust receiver,
In a state where the lever is in contact with the thrust receiver, an arcuate slit that allows the lever to rotate forward is provided in a contact portion between the bolt hole provided in the arm and the thrust receiver of the lever. An excavator characterized in that the lever and the arm are fastened by a clamp bolt that passes therethrough. A cutter head having a lever with a cutter bit attached to the tip, an arm that pivotally supports the lever, and a boss to which the arm is fixed is provided, and the arm is restricted from rotating rearward of the lever. In the excavator with arm side thrust receiver,
An excavating machine characterized in that the lever and the thrust receiver are fastened with a clamp bolt that is cut when a predetermined force or more is applied while the lever is in contact with the thrust receiver.

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