JP2001323503A - Thrust plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thrust plate which can be removed easily and the exchanged quickly. SOLUTION: A boss 11 as one member constituting a joint section for construction machinery is installed, and the thrust plate 13 is fixed at the end section of the boss 11 by a knock pin and a bolt. The other member constituting the joint section is arranged outside the thrust plat 13, and a pin 3 is set to penetrate boss 11 and the thrust plate 13 which, the thrust plate 13 is provided with a screw hole 16 in which a drawing bolt is screwed in the thrust plate 13 to be drawn. The screw hole 16 is clogged with a plug 27 for preventing the intrusion of dust.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thrust plate provided at a joint for connecting members by pins in a construction machine configured as a hydraulic shovel, a crane, or an application machine thereof.

[0002]

2. Description of the Related Art A thrust plate is provided at a joint of a multi-joint front of a hydraulic excavator. The thrust plate is provided as a replaceable member when worn by frictional force due to an axial load during excavation work. The thrust plate strikes a hole provided in the end face of the boss welded to one member to be connected, and fits tightly,
And it is fixed and attached by a retaining bolt and a knock pin for receiving a load in a thrust direction (a direction perpendicular to the connecting pin). The outer surface of the thrust plate is provided so as to protrude outward from the end surface of the boss, so that it contacts the sliding surface of the other member to be connected. The thrust plate is provided with a screw hole therethrough. Such a screw hole is used when the thrust plate is replaced, in which a pull-out bolt is screwed and pressed against the bottom surface of the hole at the end face of the boss to pull out the thrust plate from the hole at the boss end face. The reason for providing such empty screw holes is that the thrust plate is tightly fitted into the hole of the boss, and when the excavator is used for a long period of time, for example, the joint connecting the bucket to the arm. In this case, a load is applied to the thrust plate due to the frictional force of the bucket, and the thrust plate is difficult to remove due to deformation of the knock pin or intrusion of dust into the knock pin mounting hole.

[0003]

As described above, the thrust plate has an empty screw hole for removing the thrust plate. However, in particular, in the case of the thrust plate at the joint for attaching the bucket to the arm, the empty screw is used. Dust may intrude into the holes, or the threads may be deformed due to dust galling, etc., which may require removal of the dust from the screw holes or make it difficult to insert the bolts for pulling out. There is a problem that it takes time and effort to pull out.

[0004] In view of the above problems, an object of the present invention is to provide a thrust plate having a structure in which the thrust plate can be easily removed and the thrust plate can be quickly replaced.

[0005]

According to a first aspect of the present invention, there is provided a thrust plate, wherein a boss is provided on one member constituting a joint of a construction machine, and the thrust plate is fixed to both ends of the boss with a knock pin and a bolt. When the other member constituting the joint portion is arranged outside the thrust plate, the other member, the thrust plate, a pin is penetrated through the boss to form a joint portion, and when the thrust plate is pulled out, In a construction machine having a screw hole into which a pull-out bolt is screwed, a plug for preventing intrusion of dust is packed in the screw hole.

As described above, if the screw holes for pulling out provided on the thrust plate are closed with plugs, dust can be prevented from entering the screw holes, and the screw threads can be seized by biting of the dust. Since the deformation can also be prevented, when the thrust plate is replaced, the bolt for pulling out can be easily screwed into the screw hole if the plug is removed, and the thrust plate can be easily replaced.

[0007] The thrust plate of the second aspect is the first aspect.
Wherein the plug comprises a bolt with a square hole screwed into the screw hole.

As described above, if a bolt with a square hole is used as a plug to fill the screw hole, the bolt with the square hole can be easily removed by twisting the bolt in the opposite direction of the screwing direction.

[0009] The thrust plate of the third aspect is the first aspect.
Wherein the stopper is a rubber stopper or a resin stopper.

If a rubber stopper or a resin stopper is used as described above, the stopper can be provided at a relatively low cost.

[0011]

FIG. 1 is a side view showing the distal end side of a multi-joint front of a hydraulic shovel as an example of a construction machine having a joint to which a thrust plate of the present invention is applied.
In FIG. 1, 1 is an arm, 2 is a bucket, 3 is a pin for attaching the bucket 2 to the arm 1, 4 is an arm cylinder,
Reference numerals 5 and 6 denote links. Both ends of the arm cylinder 4 are connected to the arm 1 and the links 5 and 6 by pins 7 and 8, respectively. The links 5 and 6 are connected to the arm 1 and the bucket 2 by pins 9 and 10, respectively. You.

FIG. 2 is a cross-sectional view showing a joint for rotatably attaching a bucket 2 to the arm 1 with a pin 3.
Reference numeral 11 denotes a boss welded to the arm 1. In order to reduce the weight of the boss 11, an intermediate portion is constituted by double cylinders 11a and 11b. A bush 12 is fitted on the inner surface of the boss 11. At both ends of the boss 11, circular recesses 11c are formed, and a circular thrust plate 13 is tightly fitted into the recess 11c as shown in the side views of FIGS. The thrust plate 13 is fixed to the boss 11 by a plurality of bolts 14 for retaining and a plurality of knock pins 15 receiving a force in a thrust direction (a direction perpendicular to the pin 3). Further, the thrust plate 13 is provided with a plurality (two in this example) of screw holes 17 for screwing the pull-out bolts 16 (see FIG. 5).

Reference numeral 20 denotes a bracket of the bucket 2, and a circular sliding plate 21 is welded to a surface of the bracket 20 facing the thrust plate 13. A bush 2 is provided in a hole 22 formed in the bracket 20 and the sliding plate 21.
3 are fitted.

The pin 3 is connected to the bracket 20 or the sliding plate 2.
1 is inserted through a bush 23, is inserted through a boss 11 through a bush 12, is inserted through a thrust plate 13, and the detent piece 3a is detented on one bracket 20 by a bolt 24 (or metal fitting). Then, a stopper 25 is attached to the tip of the pin 3 with a bolt 26.

In this embodiment, the bolt 2 with the square hole 27a shown in the end view of FIG. 4A and the sectional view of FIG.
4 is screwed into the drawing screw hole 17 so that its tip does not protrude from the outer surface of the thrust plate 13 as shown in FIG.

By screwing the bolt 27 as a plug into the screw hole 17 as described above, earth and sand can be prevented from entering the screw hole 17 and the screw thread can be prevented from being deformed due to the bite of dust. When replacing, bolt 27
5 and as shown in FIG.
Is screwed into the screw hole 17 and pressed against the bottom surface of the concave portion 11c of the boss 11, whereby the thrust plate 13 can be removed from the concave portion 11c.

If such a bolt 27 with a square hole is used, the bolt 27 can be securely and easily removed by twisting the bolt 27 with a standardized tool.

As shown in FIG. 4D, a rubber or resin stopper 29 can be used at a low cost. In this case, the engaging portion 2 for engaging the hook-shaped pulling tool
If the stopper 29 having the plug 9a is used, the stopper 29 can be easily removed with one touch.

The present invention can be applied to the pins 7 to 10 shown in FIG. In addition, it is applicable to other joints of the articulated front of the excavator, the connection between the hydraulic cylinder and the articulated front or revolving structure, and also to the thrust plate of the applied machine of the excavator or the joint of the crane or the applied machine. it can.

[0020]

According to the first aspect of the present invention, since the screw hole for pulling out provided in the thrust plate is closed with the plug, dust is prevented from entering the screw hole, and the screw thread is caught by the dust. Since the deformation due to galling can be prevented, if the thrust plate is removed at the time of replacement of the thrust plate, the bolt for pulling out can be easily screwed into the screw hole, and the thrust plate can be replaced easily and quickly.

If a bolt with a square hole is used as a plug for filling the screw hole, the bolt with a square hole can be easily removed by twisting the bolt in the opposite direction of the screwing direction.

According to the third aspect, if a rubber or resin stopper is used as the stopper, the stopper can be provided at a low cost.

[Brief description of the drawings]

FIG. 1 is a side view showing a distal end side of a multi-joint front of a hydraulic shovel having a joint to which a thrust plate of the present invention is applied.

FIG. 2 is a sectional view showing a joint between the bucket and the arm in FIG. 1;

FIG. 3 is a side view showing a state where a pin is not mounted on the joint shown in FIGS. 1 and 2;

FIGS. 4A and 4B are an end view and a side view, respectively, showing an example of a plug used in the present invention; FIG. 4C is a cross-sectional view showing a state where the plug is inserted into a screw hole of a thrust plate; D) is a sectional view showing another example of the stopper used in the present invention.

FIG. 5 is an explanatory diagram of drawing of a thrust plate by a drawing screw.

[Explanation of symbols]

1: arm, 2: bucket, 3: pin, 4: arm cylinder, 5, 6: link, 7 to 10: pin, 11: boss,
11c: circular recess, 12: bush, 13: thrust plate, 14: bolt, 15: knock pin, 16: screw hole, 17: pull-out bolt, 20: bracket, 2
1: sliding plate, 23: bush, 25: stopper, 2
7: square hole bolt, 29: rubber or resin stopper

Claims (3)

[Claims] 1. A boss is provided on one member constituting a joint of a construction machine, a thrust plate is fixed to an end of the boss with a knock pin and a bolt, and the other constituting a joint outside the thrust plate. A construction machine comprising: a member that is arranged to penetrate a pin through the other member, the thrust plate, and the boss to form a joint; and the thrust plate has a screw hole into which a pull-out bolt is screwed when the thrust plate is pulled out. 3. The thrust plate according to claim 1, wherein the screw hole is filled with a plug for preventing dust from entering. 2. The thrust plate according to claim 1, wherein said stopper comprises a square-hole bolt screwed into said screw hole. 3. The thrust plate according to claim 1, wherein said stopper is a rubber stopper or a resin stopper.