JPH0739674B2 - Rock-crushing rod and its assembling method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rock breaking rod mounted on a ship such as a floating crane ship and a method for assembling the rock breaking rod. In particular, the cutting edge portion of the rock breaking rod for grinding the rock at the bottom of the water by a drop impact can be divided. It relates to the structure of the connecting portion.

[0002]

2. Description of the Related Art Conventionally, when it has been necessary to crush the bedrock on the bottom of the sea for harbor construction, bridge foundation work, etc., a rocking rod is lifted by a crane equipped on a floating crane ship to a desired height, and the clutch is engaged. A method is adopted in which a crushed rock rod is dropped by gravity to crush the bedrock by cutting, and crushed rock is dredged in a grab bucket. That is, as shown in FIG. 15, a rock crushing rod 22 lifted by a crane 21 and a winch 24 from a pontoon 20 floating on the water surface is dropped by its own weight toward a rock bed 23 at the bottom of the water to crush the rock bed 23. It is something to do.

[0003] The edge of the rock breaking rod 22 is generally hardfacing welded for wear resistance, but the rock breaking rod 22 itself has a weight of 25 to 40 tons. The impact on the blade is tremendous, and it is unavoidable that the cutting edge part will be deformed or worn out at an early stage. This crushed rock rod 22 is integrally formed by casting, and if the cutting edge portion is worn away beyond an allowable amount, the crushing effect is significantly reduced.
The crushed rock rod 22 has to be removed from the ground and transported to a factory for repair work, which requires a great deal of labor and has a drawback that the burden of labor and cost is great. In order to omit this repair work, it is sufficient to replace the crushed rock rod 22 with a new one. However, it is a waste of material to replace the whole crushed rock rod 22 only the blade portion of which is worn away, and it is also costly. Is.

In order to cope with the above, a structure in which a crushed rock rod is divided into two is provided (Jitsuko 63-32228).
(See the official gazette). This makes the main body of the crushed rock rod and the cutting edge intricate in a concavo-convex relationship, and punches a hole communicating with that part,
A connecting shaft is inserted into the hole to allow disassembly,
The connecting rod is covered with an elastic layer, metal disks are applied to both ends,
A snap ring is used to prevent the hole from coming off. With such a configuration, when the blade tip is worn out, the connecting shaft can be pulled out to separate only the blade tip from the main body, and the blade tip can be replaced with a new one, thereby eliminating waste of materials.

[0005]

However, in such a conventional two-division crushed rock rod, the cutting edge is connected to the main body only by the connecting rod, and therefore the impact force when the rock is collided during use. Due to the stress on the connecting part between the cutting edge and the main body, the cutting edge may fall off or be damaged,
There was a drawback that it was not practical. Further, in order to prevent such dropout or damage, it is necessary to increase the strength of the connecting portion, so that the shape of the convex and concave portions and the diameter of the connecting shaft are inevitably large.

Further, since the main body and the cutting edge are connected by the shape of the corner, the corner becomes a place where stress at the time of collision is concentrated, which may cause a crack, and the connecting shaft is pulled out by the snap ring. Since it is stopped, there is a problem that there is a high possibility that it will fall out due to an excessive load from the outside.

Therefore, the present invention improves the structure of the connecting portion of the above-described two-divided rock-crushing rods so that the cutting edge will not be damaged or fallen off due to the impact and excessive load at the time of falling, and stable rock-crushing work can be performed. The purpose is to obtain a crushed rock rod and a method for assembling the same.

[0008]

In order to achieve the above object, the present invention comprises a convex portion integrally formed at the tip of the main body, and a concave portion formed at the cutting edge corresponding to the convex portion. ,
The structure of the crushed rock rod in which the spool and the wedge for fixing are inserted into the through holes provided at the two places penetrating the above-mentioned convex portion and the concave portion and both ends of the through hole are closed by using the retaining metal fittings for retaining. provide. The main body and the cutting edge have a contact surface where both are in close contact with each other and a curved surface where both are not in close contact with each other, and are fitted by the convex portion and the concave portion, and the tip portion of the convex portion and the concave portion. A gap is formed in the innermost part of the.

Further, after the convex portion of the main body is fitted in the concave portion of the cutting edge, the spool is inserted into a through hole provided through the main body and the cutting edge while forming a predetermined gap, and the spool is temporarily welded. After fixing, insert a wedge formed in advance in the through hole and drive it evenly, after welding the entire circumference of the groove part, retighten the wedge and remove the excess part of the wedge. Provided is a method for assembling a crushed rock rod in which a mating surface of a spool and a wedge is cut and welded, and a perforation hole is welded all around by using a fastener.

[0010]

According to the present invention, since the main body and the cutting edge are connected by using the through hole provided at two places and the spool and the wedge inserted through the through hole, when the rock breaking rod falls, Based on the stress distribution effect of the surface receiving the impact load, it is possible to prevent the stress concentration on the convex portions and the concave portions of the main body and the cutting edge to prevent damage due to the impact load. Furthermore, since the main body and the cutting edge have a contact surface where both are in close contact with each other and a curved surface where both are not in close contact with each other, the convex portion and the concave portion are engaged with each other, and are connected with each other with a gap therebetween. , The impact received by the cutting edge is firmly received by the contact surface and transmitted to the main body, and the structural strength of the connecting portion is improved, and the stress due to the impact is also dispersed by the contact surface, the bent surface and the gap, and the normal When the corner portion is formed, stress concentration on the corner portion can be eliminated, and the effect that no crack is generated can be obtained.

When the blade edge is worn out, the convex portion of the main body is fitted into the separately prepared concave portion of the blade edge, and then the spool is inserted into the through holes provided at two positions and fixed by temporary welding. After that, insert a wedge formed in advance in the through hole and drive it evenly, after welding the entire circumference of the groove part, retighten the wedge and cut the excess part of the wedge. By welding the mating surfaces and welding the entire circumference of the through hole using the fastener, it is possible to easily replace only the cutting edge with a new one, and waste of materials can be eliminated.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a rock breaking rod according to the present invention will be described below with reference to the drawings. As shown in FIGS. 1 and 2,
The crushed rock rod 1 having a chisel shape is divided into a main body 2 and a cutting edge 3, and a convex portion 4 is integrally formed at the tip of the main body 2. A recess 5 is formed in the blade edge 3 at a portion corresponding to the portion 4. In the illustrated example, the divided portion of the main body 2 and the cutting edge 3 is approximately 1 / from the tip of the cutting edge 3.
It is provided at four locations. It should be noted that this divided portion may be selected at an appropriate position according to the size and shape of the crushed rock rod.

Then, the convex portion 4 and the concave portion 5 are fitted to each other, and the spool 7 and the wedge 8 are inserted into the through holes 6 and 6 provided at two places so as to penetrate the both, and the stoppers 9 and 9 are attached. Is used to prevent the spool 7 and wedge 8 from coming off.

The details of the fitting and fixing portion between the convex portion 4 and the concave portion 5 and the assembling sequence will be described with reference to FIG. That is, the main body 2 and the cutting edge 3 have a contact surface 10 in which they are in close contact with each other and a bent surface 11 in which they are not in close contact with each other, and the convex portion 4 and the concave portion 5 are fitted to each other. A gap 12 is formed between the tip of the concave portion and the innermost portion of the concave portion 5. A groove 10a is provided outside the contact surface 10. The contact surface 10 and the bent surface 11 are previously formed as smooth surfaces by a grinder finish. A step 6a is formed in the vicinity of the end of the through hole 6, and a locking portion 13 slightly protruding from the main body 2 into the through hole 6 is present.

At the time of assembly, as shown in the drawing, the convex portion 4
After fitting into the recess 5, the spool 7 is inserted in the through hole 6 while forming a gap 20 between the spool 7 and the locking portion 13 of the main body 2 with the neck of the spool 7 facing upward in the drawing. The spool 7 is inserted, and the spool 7 is fixed by temporary welding so that it does not come out downward in the drawing. At this time, the spool 7 is locked by the locking portion 13.
Is positioned.

Subsequently, the wedge 8 is inserted into the through hole 6, and the wedge 8 is evenly driven so that the contact surface 10 is in close contact. The wedge 8 is formed long in advance so that the tightening described later can be performed. Next, the groove portion 10a is welded all around, and the wedge 8 is further driven to perform tightening, and then an excess portion of the wedge 8 is gas-cut. Next, the mating surface 14 of the spool 7 and the wedge 8 is welded, the stopper metal 9 is inserted, and the perimeter of the through hole 6 is welded at the step 6a to complete the assembly.

The spool 7 is shorter than the entire length of the through hole 6, and as shown in FIGS. 4 to 6, the guide portion 1 is provided with a circular arc portion 7a and a groove 7b inclined opposite to the arc portion 7a in the longitudinal direction.
Have 5. The arcuate portion 7a is formed with a U-shaped notch portion 7c which engages the convex portion 4 with being separated from each other. Further groove 7b
A groove 16 is formed at both ends of the groove.

As shown in FIGS. 7 to 9, the wedge 8 has a circular arc portion 8a and a guide portion 17 composed of a protruding portion 8b inclined on the opposite side, and the guide portion 17 is a guide for the spool 7. Engage with section 15. Therefore, FIGS.
As shown in FIG. 7, by engaging the protruding portion 8b of the wedge 8 with the guide portion 15 of the spool 7 and driving the wedge 8, the spool 7 and the wedge 8 come into close contact with each other and are inserted and fixed in the through hole 6. To be done.

The stopper 9 is an oval plate that closes the through hole 6 and covers the opening of the through hole 6 and then welds the periphery thereof.

At the time of actual use, by fitting the convex portion 4, the cutting edge 3 and the concave portion 5 of the main body 2 at the work site, the spool 7 and the wedge 8 are used to connect the both.
The crushed rock rod 1 can be easily assembled. Then, the rock-crushing rod 1 is lifted by a crane equipped on a floating crane ship or the like, and the clutch is disengaged so that the rock-crushing bar 1 is allowed to drop on the bedrock by its own weight to perform rock-crushing.

In this embodiment, the main body 2 and the cutting edge 3 are connected to each other by the through holes 6 and 6 provided at two places, the spool 7 and the wedge 8 inserted through the through holes 6 and 6, and thus the main body is connected. It is possible to prevent damage to the convex portions 4 and the concave portions 5 of the blade 2 and the cutting edge 3 in advance. That is, when the crushed rock rod 1 is dropped onto the rock mass 23, the blade edge 3 is parallel to the rock mass 23 due to rolling of the ship, yawing and displacement of the suspension rope to which the crushed rock stick 1 is attached, or the undulating shape of the rock mass 23 itself. It is extremely rare to hit the rock, and normally, as shown in FIG. 13, for example, one of the lower corners of the cutting edge 3 is in a posture of landing on the rock first. In the case of this embodiment, assuming that the surfaces receiving the impact load at both corners of the cutting edge 3 are A and B, the through holes 6 and 6 and the connecting portion structure are provided at two locations in the vicinity of the surfaces A and B. As shown in FIG. 14, based on the stress distribution effect by the surfaces A and B, stress concentration on the convex portions 4 and the concave portions 5 of the main body 2 and the cutting edge 3 is eliminated to prevent damage due to impact load. You can

Furthermore, in the present embodiment, the main body 2 and the cutting edge 3 are in contact with each other as shown in FIG.
Since the convex portion 4 and the concave portion 5 are fitted with each other by having the bent surface 11 that is not in close contact with each other and are connected through the gap 12, the contact surface 10 and the bent surface 11 and Gap 1
Even with 2, the stress due to impact can be dispersed.
That is, when the bent surface 11 is eliminated to form a normal corner shape as in the conventional example, this corner becomes a location where stress at the time of collision concentrates, which causes a crack to occur. However, in this embodiment, the contact surface 10 that is in close contact receives the load due to the collision, and the stress is dispersed by the bent surface 11 and the gap 12 that are not in close contact.

In this embodiment, the shape of the cutting edge 3, the width of the cutting edge, the material, etc. can be freely changed, and the cutting edge 3 can be changed to a cutting edge having an irregular shape according to the strength of the bedrock 23 at the work site. Can improve work efficiency.

[0024]

According to the present invention described above, since the main body and the cutting edge are connected by using the through holes provided at two places and the spool and the wedge inserted through the through holes, the structure of the connecting portion is provided. The strength of the cutting edge does not drop or break due to the stress on the connecting part between the cutting edge and the main body due to the impact force when it collides with the rock mass, and in particular the shape of the convex and concave parts to increase the strength of the connecting part There is no need to increase the size of the connection member or the connecting member, which is advantageous in terms of cost. Furthermore, since the main body and the cutting edge have a contact surface where both are in close contact with each other and a curved surface where both are not in close contact, the impact received by the blade edge is firmly received by the contact surface, and due to the curved surface and the gap. It is possible to disperse the stress due to impact and prevent the occurrence of cracks.

Further, at the time of assembling the rock-crushing rod, after inserting the spool into the through hole and fixing it, the wedge formed in advance is inserted into the through hole and is evenly driven, and the entire circumference of the groove is welded. After tightening, the wedge is retightened, the excess part of the wedge is cut, and the entire circumference of the through hole is welded using a fastener, so that the shape of the through hole is temporarily impacted. Even if there is a deformation that occurs, it can be dealt with by the above tightening, and a strong connection structure can be obtained. The blade tip can be easily replaced on site, and by welding the stoppers to the through hole, the spool and wedge will not fall off even if an excessive load is applied from the outside, making it practical. Demonstrate the effect of high.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is a plan view of FIG.

3 is an enlarged sectional side view of a portion of FIG.

FIG. 4 is a side view showing a spool.

FIG. 5 is a front view showing a spool.

FIG. 6 is a plan view showing a spool.

FIG. 7 is a side view showing a wedge.

FIG. 8 is a front view showing a wedge.

FIG. 9 is a plan view showing a wedge.

FIG. 10 is a side view showing the relationship between the spool and the wedge.

FIG. 11 is a side view showing the relationship between the spool and the wedge.

FIG. 12 is a plan view showing the relationship between the spool and the wedge.

FIG. 13 is a schematic diagram illustrating a state when the rock-crushing rod according to the present embodiment is used.

14 is a cross-sectional explanatory view of a C portion of FIG.

FIG. 15 is a schematic diagram for explaining a usage state of a normal rock breaking rod.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Rock-crushing rod 2 ... Main body 3 ... Blade 4 ... Convex part 5 ... Recessed part 6 ... Through hole 7 ... Spool 8 ... Wedge 9 ... Stopper 10 ... Abutting surface 11 ... Bent surface 12, 20 ... Gap 13 ... Locking part 14 … Mating surface 15, 17… Guide part

Claims (4)

[Claims] 1. A convex portion integrally formed at a tip portion of a main body,
The protrusion is provided with a concave portion formed at the blade edge corresponding to the convex portion, and the fixing spool and wedge are inserted through the through holes provided at two positions penetrating the convex portion and the concave portion to prevent slippage. A crushed rock rod characterized in that both ends of the through hole are closed by using fasteners. 2. The body and the cutting edge have a contact surface where both are in close contact with each other and a curved surface where both are not in close contact with each other, and are fitted by the convex portion and the concave portion, and the tip portion of the convex portion. The crushed rock rod according to claim 1, wherein a gap is formed in the innermost portion of the recess. 3. The rock breaking rod according to claim 1 or 2, wherein the through holes formed in the main body and the cutting edge portion are oval. 4. After fitting the convex portion of the main body into the concave portion of the cutting edge,
Insert the spool into the through hole provided through the main body and the cutting edge while forming a predetermined gap, and fix the spool by temporary welding, then insert the wedge formed in advance into the through hole. Drive evenly, after welding the entire circumference of the groove, retighten the wedge, cut the excess part of the wedge and weld the mating surface of the spool and the wedge,
A method for assembling a crushed rock rod, characterized in that the perimeter welding of a through hole is performed using a fastener.