JPH045393A - Rock drill - Google Patents

Abstract

PURPOSE: To prevent the mixing of a pollutant by installing a base seal onto a base frame, making them cooperate with each other through a conical seal and a recess, and forming a space between the base seal and the recess and forming an air seal. CONSTITUTION: A mechanism driving a shaft is set up into the base frame 18 of the rock drill, and the shaft is connected to a cone 10 and the cone 10 is turned and driven on a bearing surface 14. A lubricating device 26 and an annular through 27 are fitted to the spherical bearing surface 14, and a base seal 80 is attached onto the base frame 18. Surfaces 84, 86 with the inclined section 82 of the base seal 80 and the surfaces 58, 70 of a conical seal are formed in a spherical shape, and moved concentrically when a head is rotated. An air seal 119 is installed between the inclined section 82 and a cone supporting member 16. Accordingly, the infiltration of a pollutant can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a rotating rock drill. More specifically, the present invention relates to a dust seal for use in a rotating rock drill.

[Prior Art] It has been very difficult to realize an effective dust seal that can be used in conical or rotating rock drills. The internal working parts of a rock drill (bearings, gears, shafts, oil pumps, lubricants) need to be protected from both rock dust and other contaminants generated during rock drilling.

Otherwise, it would be very costly to maintain the jackhammer in good condition. No matter how good a rock jackhammer is, if the rock dust cannot be removed, the equipment is useless.

A rotating labrynth seal, such as that disclosed in U.S. Pat. No. 3,118,623,
1) is very efficient in eliminating dust, but due to high cost, speed limitations, or inadequate load carrying capacity of large roller thrust bearings, the dimensions of the device are limited. limited to small. today,
Or, in order to produce the kind of crushed rock that will be needed in the future, a rather large rock drill will be required.

U.S. Patent Nos. 2.224.542 and 2.832.54
Flexible seals have also been used, such as those disclosed in No. 7, No. 4, 192.472. Such a seal has a frustoconical member fixed between the rock drill head and the head support and can be designed for use on larger types of rock drills. However, given the intense movement of the jackhammer head, these plexiple seals have a short lifespan.

Rubbing seals have also been used. This seal has a structure in which one part of the seal is fixed to a base frame and the other part is attached to a pivoting conical head. This seal exposes a surface in the constantly moving track to the centerline of the jackhammer. A very fine dust of rock then adheres to this surface. As this surface moves inward, most of the dust is scraped away, but some passes between the sealing surfaces. Over time, this dust accumulates to a destructive level. Efforts have been made to utilize internal air pressure, but these efforts have not been sufficient due to the difficulty in forcing out the dust, and there are no effective devices for resisting air flowing into internal working parts. Not developed.

[Summary of the Invention] The main object of this invention is to provide a dust seal for use in a rotating rock drill. The jackhammer utilizes a modified rubbing-type seal, which is used in conjunction with an air circulation system to keep dust and other contaminants out of the internal working parts.

A further object of the invention is to provide a dust seal of the type described above, which combines a base seal and a conical radial seal. In this device, a resilient support device sealingly engages two surfaces of these members and maintains the other two surfaces spaced apart. Air flows between these spaced surfaces to prevent contamination.

To achieve these objectives, the base seal is mounted on the base frame and cooperates with the conical seal via a recess. The concave and convex portions of these surfaces are arranged to move relatively parallel in the pivoting movement of the cone. The convex portion has a thickness that is less than the distance between the upper and lower ends of the concave portion. A resilient device holds the base seal upwardly relative to the conical seal for a sealing engagement and also defines a space between the lower surfaces to prevent contamination from entering. Forms an air seal. A deflection device is provided in the concave portion to reverse the direction of the incoming air, so that the air can efficiently flow out from between the base seal and the conical seal.

The seal between the base seal and the conical seal has a low friction plastic insert that operates in combination with a low friction thrust bearing insert.

The present invention will become clearer from the embodiments described below with reference to the accompanying drawings.

[Example] Hereinafter, the present invention will be described in detail based on the accompanying drawings.

First, refer to FIG. The reference number IO represents the cone or head of the rock drill.

This cone consists of a mantle and a ball (b).
owl) (not shown). The mantle and ball work together to break up the rock. Said cone has a convex spherical bearing surface 12 on the underside. Bearing surface 1
2 is a spherical bearing surface 1 provided on the upper side of the cone support member 16 fixed to the base frame 18 of the rock drill.
It is slidably supported on 4.

The base frame 18 has a mechanism (
(not shown) is housed therein. The shaft is connected to the cone of the jackhammer, and the bearing surface 14
Rotate the cone on top. The jackhammer base frame 18 cooperates with an outer wall 20 (see FIGS. 4 and 5) and other support structures that are well known to those skilled in the art. It is therefore not shown here.

The spherical bearing link surface 14 has a suitable support surface, which has a lubricating device 26 and an annular trough 27. Hydraulic lift is applied to the trough 27. The aforementioned bearing surface also has a sealing ring 28,
The sealing ring 28 has an adjacent thrust insert 29a and an oil sealing insert 29 on the outer periphery of the bearing surface 14. The thrust insert 29a is made of durable plastic or metal to prevent excessive pressure from being applied to the seal insert 29.

Cone support member 16 has a vertical sealing band or ring 3o. The ring 3° engages with the sealing ring 28 in a partially overlapping manner and extends upward. This ring 3o cooperates with a lower seal 32 which is engageable with the sealing ring 28. The ring 30 forms an outer wall for a water cooling duct 36. The sealing ring 28 is biased upwardly by a plurality of spring supported plungers 38 into engagement with the bearing link surface 12 of the cone. The aforementioned plunger 38 is attached to the outer notch portion 40 of the cone support member 16. If the lubricating oil associated with the cone leaks through the seal insert 29, it flows downward by gravity to an annular pickup trough 44 and then through one or more of the cone support members 16. Flows downwardly into the interior of the device via exhaust passage 42 and lateral port 46.

A dust seal device that cooperates with this rock drilling machine prevents contaminants such as dust from entering between the cone and the inner rock drilling part. The dust sealing device has a conical sealing ring 50 on the upper side.

The sealing ring 50 is attached to a downwardly facing shoulder 52 of the cone.
It is fixed to by a plurality of cap screws 54. The seal ring 50 has a ramp 56 angled downwardly from the inside, and the ramp 56 has a smooth surface 58 on the underside. Cone 10 has a downwardly extending flange 62 at its outer periphery. The flange 62 is the cap screw 6
A conical sealing ring 64 supported at the bottom by 6
has. Seal ring 64 has a downwardly angled ramp 68. The sloped portion 68 has a smooth surface 70 on the upper side.
has. The two surfaces 58,70 are concentric and form a recess 72 therebetween.

The dust seal according to the invention has a vertically extending base seal 80. The base seal 8o has a sloped portion 82 angled upwardly and outwardly, and the sloped portion 82 has a recess 7
It extends into 2. The surfaces 84.86 of the ramp 82 of the base seal 80 and the surfaces 58.70 of the conical seal have spherical shapes that align with each other and are movable concentrically as the head pivots.

The thickness of the ramp 82 of the base seal 80 is less than the width of the recess 82, and the ramp 82 is abutted against the upper surface 58 of the recess by a plurality of spring-loaded plungers 90. The plunger 90 is connected to the cone support member 16
a flat upper end 94 that is slidably received in a recess 92 and engages the bottom of the base seal 80;
has.

Base seal 80 has a flange 96. Flange 9
6 is engaged with the outer vertical surface of the cone support member I6 through a gap, and forms a cylindrical surface with respect to the base seal. An inner end 82a of the inclined portion 82 is slidably engaged with the cone support member 16 through a gap. The number of spring-loaded plungers 90 may be variable or may be greater to ensure an even upward force around the circumference of the cone (e.g., it is desirable to use 20 plungers. As shown in Figure 2, the three plungers 90a have tapered or conical ends that extend into similarly shaped recesses 98 in the base seal. These plungers assist plunger 90 in lifting the base seal upwardly and also lock the base seal from rotation.

The surface 84 of the inclined portion 82 of the base seal is made of Teflon (Teflon).
An air and dust seal insert 100 made of a low friction plastic such as eflon (trade name) is installed. Seal insert 100 is Notchi 10
2 and protrudes from the notch 102 to engage the surface 58 of the upper seal ring 50. The outer surface of seal insert 100 is aligned with the arc centers of all spherical members. The upper corner of the seal insert 100 is resiliently biased against the spherical surface 58 by an underlying O-ring 104. Adjacent to the seal insert 100 and towards the inside of the rock drill is another low friction insert 106 made of Teflon or Delrin. An insert 106 is also seated within notch 102. Insert 106 has a thrust member to support the force of spring-loaded plunger 90. Seal insert 100 can accept some thrust forces, relieving pressure on insert 106.

As previously described, a small space 110 is formed between the base seal 82 and the surface 70 of the recess when the base seal 82 is lifted upwardly to engage its seal insert 100 and insert 106 with the surface 58. The dimensions and arrangement of the members are predetermined. this space 11
0 forms an outlet that extends over the entire circumference for air flowing to the outer end of the sloped portion 82 of the base seal, or
This point will be explained later.

Reference numeral 114 represents a fitting for inflow from a source of pressurized air. Preferably, these fittings are provided in pairs and spaced 180 DEG from each other to provide an efficient and balanced supply of air to the cone support member 16. Each of the fittings communicates with a vertical port 116 (see FIG. 3) in cone support member 16. Port 116 is located in the middle of plunger 90.90a. port 1
16 communicates with an annular passageway 118 formed between cone support member 16 and base seal 80 . An air seal 119 is provided between the inclined portion 82 and the cone support member 16 to prevent air from escaping upward. Further, an air seal 119a is provided between the downwardly extending flange 96 and the cone support member 16 to prevent air from escaping downward. Passage 118 may include a plurality of air ducts or passages 120
It communicates with The number of passages 120 is 36, and passage 1
20 extends from the inner end to the outer end of the sloped portion 82 of the base seal. The pressurized air guided to the annular passage 118 is pushed out from the upper end of the inclined portion 82,
It is discharged via space 110. As a result, an air block is created to prevent contaminants from entering between the cone of the rock drill and the internal components. In the embodiment, the outer end of the base seal ramp 82 supports a vertical deflector 122. Deflector 122 has a bottom 124 angled toward the inner end of base seal ramp 82. Therefore, the air passage 120
The air discharged through the outer end is reflected and its direction is reversed, which more effectively prevents the inflow of pollutants.

In some embodiments, the deflector 122 is a syringe located at the end of the ramp 82 of the base seal.
hlink fit).

Next, a description will be given with reference to FIGS. 4, 5, and 6. Air pumped to fittings 114 and ports 116 is supplied from a blower 130 and filter 132 suitably mounted on the rock drill, such as on the outer wall 20.

However, if desired, these elements can also be formed from part of a separately mounted filter and blower mechanism independent of the rock drill. In the apparatus shown, the filter and blower assembly is supported on a bracket 134 secured to the wall 20. Air inflow to the blower is via a filter, and an outflow conduit 136 from the blower leads to a fitting 138 in the wall. This fitting 138 communicates with an inwardly extending passageway 140 on a vertical web 142 that is integral with the rock drill. The inner end of the passageway 140 extends upwardly within the web to a tee fitting 144. A conduit 146 extends from the tee fitting 144 to inflow fittings 114 on diametrically opposite sides of the cone support member.

During operation of the rock drill, the base seal 80 and the corresponding spherical surfaces of the recess 72 move concentrically around the entire circumference of the cone's pivoting motion. The length of the base seal 80 extending into the recess is such that throughout the stroke a portion of the base seal is always engaged within the recess and always in a telescoping relationship.
g relation) is maintained and an elongated space 110 is formed between the lower surface 70 and the sloped portion 82. FIG. 1 shows the cone 10 in the middle of its stroke. The dashed line shows the inner end of the inclined portion 68 closest to the base seal. Passage 1
By providing a large number of spaces 110, air can be evenly distributed through the spaces 110.

If any contaminants enter the recess 72, the seal insert 100 prevents the contaminants from entering the internal parts of the rock drill. The seal insert resiliently engages surface 58 with its own resiliency and O-ring 104 to extend seal life. The upward force of the base seal 80 on the upper conical seal ring 50 is supported by the seal insert 100 and the insert 106.

Deflector 122 reverses the direction of air entering the duct to efficiently move the air into space 100 and out of the rock drill. In the device shown, contaminants such as dust are prevented from entering the only source of ingress into the internal working components of the rock drill, namely between the cone and the cone support member, thus extending the life of the rock drill. become longer.

The embodiments described above are merely illustrative and do not limit the invention. Therefore, the rock drill of this invention can be realized in any form without departing from the spirit and scope of the invention.

[Brief explanation of drawings]

The drawings show an embodiment of a rock drilling machine according to the present invention, and FIG. 1 is a sectional view of a partial chamber of a rock drilling machine that performs a swinging motion and a dust seal, and FIG. Figure 3 is the same as Figure 1, but on the periphery to show the air intake device. 4 is a partial bottom view of an air supply device used with the dust seal according to the present invention, FIG. 5 is a sectional view taken along line 44 in FIG. 4, and FIG. It is a sectional view taken along line 6-6 in the figure. 10--Cones 12, 14--Bearing surface 16-゛°゛Cone support member 18--Base frame 72--Recess 80--Base seal

Claims (15)

[Claims] (1) a base frame; a cone of a rock drill; an internal drive and support device provided on the base frame for turning the cone; cooperating spherical surfaces provided on a base frame and a cone; a base seal provided on the base frame; a conical seal provided on the cone; and pumping air into the recess. a sealing device disposed between an upper surface of the recess and an upper surface of the protrusion; and an elastic member resiliently retaining the base seal upwardly relative to the conical seal. an apparatus, wherein one of the base seal and the conical seal has a recess, the other of the base seal and the conical seal has a projection that fits into the recess, and the recess and the projection fit into the cone. has upper and lower spherical surfaces arranged for relative concentric movement when the recess makes a pivoting motion; the elastic device has a thickness less than a distance, and the resilient device forms a sealing engagement between the upper surfaces of the two seals and also forms a space between the lower surfaces of the base. A rotating rock drill that forms a fluid air dust seal between the seal and the conical seal. 2. The pressurized air device is provided with a deflection device extending through the base seal and opening into the recess to direct flowing air into the space of the dust seal. jackhammer. 3. A rock drilling machine according to claim 1, wherein said seal includes a bottom friction insert. (4) The rock drilling machine according to claim 1, wherein the elastic device includes a plurality of compression springs engageable between the base seal and the base frame. (5) the resilient device has a plurality of spring-loaded plungers, the plungers being engageable between the base seal and the base frame, and at least some of the plungers sealing the base seal; 2. A rock drilling machine as claimed in claim 1, including socket fits in both said base seal and conical seal to prevent relative rotation of said base seal and conical seal. (6) the pressurized air device extends through the base seal and opens at the outer free end of the base seal, and a deflection device at the free end directs the escaping air downwardly into the space of the dust seal; A rock drilling machine according to claim 1, which is provided adjacently. (7) The pressurized air device extends through the base seal, opens at the outer end of the base seal, and is shaped to reverse the direction of outflowing air and direct the air into the dust seal space. 2. A rock drilling machine as claimed in claim 1, wherein a baffle having a baffle is provided at said outer end. (8) The baffle includes a ring member mounted by a recess on the outer end.
Jackhammer as described in section. 9. A rock drilling machine according to claim 1, wherein said seal includes a bottom friction insert. 10. The seal of claim 1, wherein the seal has a bottom friction insert used in combination with an adjacent bottom friction insert to form a space between the base seal and the conical seal. Jackhammer. (11) The rock drilling machine according to claim 1, wherein the elastic device includes a plurality of compression springs that can be engaged between the base seal and the base frame. (12) The elastic device has a plurality of plungers biased by a spring, the plungers are engageable between the base seal and the base frame, and at least some of the plungers are engaged with the base seal. 2. A rock drill as claimed in claim 1, wherein both the base seal and the conical seal have socket fits to prevent relative rotation of the conical seals. (13) The rock drilling machine according to claim 6, wherein the pressurized air device includes a blower, and the air passage communicates with the blower to guide air to the recess through the base seal. (14) Claim 1, wherein the pressurized air flow path has an annular flow path adjacent to the base seal, and a plurality of ducts extend from the flow path via the base seal.
The rock jackhammer described in item 3. (15) The pressurized air device includes a blower having an inlet and an outlet, and a filter provided at the inlet of the blower to filter the incoming air, and the air flow path 7. The rock drilling machine according to claim 6, wherein the rock drill communicates with an outlet of a blower and guides air through the base seal to the recess.