WO1980001530A1

WO1980001530A1 - Impact tip for impact rock breaker

Info

Publication number: WO1980001530A1
Application number: PCT/US1979/000043
Authority: WO
Inventors: R Livesay
Original assignee: Caterpillar Tractor Co; R Livesay
Priority date: 1979-01-29
Filing date: 1979-01-29
Publication date: 1980-08-07
Also published as: GB2053141A; GB2053141B; JPS55501148A

Abstract

A detachable impact tip (10) for an impact rock breaker (B) has a mounting socket (11) and an improved tooth (12) which has a rectangular base (13) abutting the socket (11), and a body (14) which is wedge-shaped in side elevation and generally spade-shaped in plan. The body (14) has smoothly rounded longitudinal margins (17), and an extremity (15) which forms a generally blunt edge smoothly rounded from top to bottom and gently convex from side to side, and smoothly curved forward margins (18) between generally triangular sides (14a) of the body (14) and said extremity.

Description

Impact Tip for Impact Rock Breaker

Technical Field

This invention relates to a removable impact tip which mounts on a shank of an impact material fracturing apparatus, or rock breaker.

Background Art

Impact tips for material fracturing devices, which are commonly called rock breakers, are subjected to enormous stresses in use, so that they ordinarily have a rather short useful life. Careful selection of materials for maximum impact resistance has produced marked improvements in these devices; but even with the best available materials the useful life of the impact. tips is undesirably brief.

The use to which impact tips are put is so different from that of devices such as bucket teeth, excavator teeth, or trencher teeth that the experience with such teeth is quite useless in engineering an improved impact tip for an impact rock breaker.

Typical tip structures for impact rock breakers are seen in U.S. patents 3,770,322; 3,922,017 ; and 4 , 068 , 742.

Disclosure of Invention The present invention is directed to providing a replaceable impact tip for an impact rock breaker which has a longer service life than do the impact tips of the prior art.

According to the present invention, a detachable impact tip for an impact rock breaker includes a mounting socket adapted for fixed attachment to a breaker shank, and a rock impacting tooth of improved shape which is integral with the socket. The tooth has a base abutting the socket, and a body on the base which is wedge-shaped in side elevation and generally spadeshaped in plan, the body having smoothly rounded longitudinal margins, an extremity which forms a blunt edge smoothly rounded from top to bottom and gently convex from side to side, and smoothly curved forward margins between generally triangular sides of the body and the extremity forming the blunt edge.

Brief Description of Drawings

Fig. 1 is a fragmentary side elevational view of an impact rock breaker provided with a detachable impact tip embodying the present invention;

Fig. 2 is a plan view of the detachable impact tip of the present invention;

Fig. 3 is a side elevational view of the detachable impact tip of the present invention; and

Figs. 4-8 are transverse sectional views taken, respectively, as indicated along the lines IV-IV, V-V, VI-VI, VII-VII, and VIII-VIII of Fig. 2.

Best Mode for Carrying Out the Invention

Referring to Fig. 1 of the drawings, an impact rock breaker, indicated generally at B, may, for exemplary purposes, be of the type disclosed in U.S. patent 3,922,017, so that it has a breaker shank B1, the lower end portion B2 of which is adapted to receive the detachable impact tip 10 of the present invention. The impact tip 10 consists generally of a mounting socket 11 having side walls 11a and top and bottom walls lib. Aligned apertures lie in the side walls 11a receive a mounting pin which detachably secures the impact tip 10 to the extremity B2 of the breaker shank B1. The impact tip 10 also includes a tooth 12 which includes a base 13 abutting the socket 11 and a body 14 on the base 13. As seen in Figs. 2 and 3, the body is wedgeshaped in side elevation and generally spade-shaped in plan.

The body 14 has effectively smooth surfaced, substantially triangular lateral faces 14a. which extend from the base 13 toward a tooth extremity 15, and it also has effectively smooth surfaced top and bottom faces 16 which extend from the base 13 to the tooth extremity 15, and which are gently convexly curved in cross section throughout their lengths as seen in Figs. 4-7. The substantially triangular lateral faces 14a are connected to the top and bottom faces 16 by smoothly rounded longitudinal margins 17 which are seen in Figs. 4-7; and a comparison of Figs. 6 and 7 with Figs. 4 and 5 shows that the generally triangular sides 14a of the body 14 gradually vanish into the smoothly rounded top and bottom margins 17a about midway between the base 13 and smoothly curved forward margins 18 which are between the generally triangular sides 14a and the extremity 15. As seen in Figs. 2 and 3, the extremity 15 forms a blunt edge which is smoothly rounded from top to bottom and gently convex from side to side so as to merge smoothly into the curved forward margins 18.

The base 13 is seen in Fig. 8 to be generally square in cross section, with substantially planar side surfaces 13a and top and bottom surfaces 13b which are connected by smoothly rounded top and bottom margins 17a that merge into the smoothly rounded longitudinal margins 17 of the body 14. As seen in Fig. 2, the top and bottom faces 16 of the body 14 are wider at the curved forward margins 18 than they are at the base 13.

Thus, the tooth may be described as having top, bottom and side surfaces which join at a leading edge that has a large radius center portion and smaller radius lateral extremities with the top and bottom sur faces diverging from the base 13 toward the small radius extremities of the leading edge.

Likewise, the top and bottom surfaces have a large radius and join the side surfaces along curves of relatively small radius which constantly decrease from the base 13 into the leading edge 15.

A typical impact tip embodying the invention has the following dimensions and radii of curvature, the "h" and "w" dimensions being, respectively, the vertical dimensions and horizontal dimensions of the correspondingly numbered sectional views, and "r" being the radius of curvature of the curve 17a or the longitudinal curve 17.

4h = .666"; 4w = 4.00"; 4r = .12" 5h = 1.07"; 5w = 3.86"; 5r = .36"

6h = 1.68"; 6w = 3.60"; 6r = .50"

7h = 2.10"; 7w = 3.50"; 7r = .62"

8h = 3.20"; 8w = 3.40"; 8r = .75"

The radii of curvature of the surfaces 16 are 8.00" throughout; the top-to-bottom radius of curvature at 15 is .12"; the transverse radius of curvature at 15 is 7.00"; the radius of curvature at 18 is .80"; and the radius of curvature at 13 is 1.12".

The length from lid to line VIII-VIII is 5.19". The distance from the various section lines to the extremity 15 is: from VIII-VIII 4.68"; from VII-VII 3.87"; from VI-VI 3.00"; from V-V 1.75"; from IV-IV .91".

The foregoing dimensions would, of course, vary proportionally for impact tips to be used with larger or smaller impact rock breaker machines.

Industrial Applicability

In use, the detachable impact tip 10 of the present invention is mounted upon a breaker shank B1 of an impact rock breaker B. The particular shape of the body 14 which is disclosed and claimed herein, and the way in which it merges into the base 13, provides greatly improved tip life as compared with tips heretofore available.

Other aspects, objects and advantages of the invention can be obtained from a study of the drawings, the disclosure and the appended claims.

Claims

1. In a detachable impact tip (10) for an impact rock breaker (B) which includes a mounting socket (11) adapted for fixed attachment to a breaker shank (B1), and a.rock impacting tooth (12) integral with said socket (11), a tooth (12) comprising: a base (13) abutting the socket (11); and a body (14) on said base (13) which is wedge-shaped in side elevation and generally spadeshaped in plan, said body (14) having smoothly rounded longitudinal margins (17), an extremity (15) which forms a blunt edge smoothly rounded from top to bottom and gently convex from side to side, and smoothly curved forward margins (18) between generally triangular sides (14a) of the body (14) and said extremity (15).

2. The tooth of claim 1 in which the body (14) has top and bottom faces (16) which are wider at the curved forward margins (18) than at the base (13) .

3. The tooth of claim 2 in which the base (13) has substantially planar side (13a) and top and bottom (13b) surfaces connected by smoothly rounded top and bottom margins (17a) which merge into the smoothly rounded longitudinal margins (17) of the body (14).

4. The tooth of claim 3 in which the generally triangular sides (14a) of the body (14) gradually vanish into the smoothly rounded top and bottom margins (17) about midway between the base (13) and the smoothly curved forward margins (18).

5. The tooth of claim 1 in which the base (13) has substantially planar side (13a) and top and bottom (13b) surfaces connected by smoothly rounded top and bottom margins (17) about midway between the base (13) and the smoothly curved forward margins (18).

6. The tooth of claim 5 in which the generally triangular sides (14a) of the body (14) gradually vanish into the smoothly rounded top and bottom margins (17) about midway between the base (13) and the smoothly curved forward margins (18).

7. The tooth of claim 1 in which the generally triangular sides (14a) of the body (14) gradually vanish into the smoothly rounded top and bottom margins (17) about midway between the base (13) and the smoothly curved forward margins (18).

8. In a detachable impact tip (10) for an impact rock breaker (B) which includes a mounting socket (11) adapted for fixed attachment to a breaker shank

(B1) , and a rock impacting tooth (12) integral with said socket (11), a tooth (12) comprising: a base (13) abutting the socket (11); effectively smooth surfaced, substantially triangular lateral faces (14a) which extend from said base (13) toward a tooth extremity (15); effectively smooth surfaced top and bottom faces (16) which extend from said base (13) to said tooth extremity (15) and which are gently convexly curved in cross section throughout their lengths; smoothly rounded longitudinal margins (17) between said lateral faces (14a) and said top and bottom faces (16); and smoothly curved forward margins (18) connecting said lateral faces (14) with said tooth extremity (15), said tooth extremity (15) being a blunt edge smoothly rounded from top to bottom and gently convex from side to side.