Chisel with double limit discs

Abstract

The present invention discloses a chisel with double limiting disks, which comprises a holding seat and a cutter head installed on the holding seat. The cutter head includes a head portion and an extension portion provided on the lower side of the head portion. A first limiting disk and a second limiting disk arranged vertically are installed between the holding seat and the head portion. The middle of the first limiting disk has a first installation through hole, and the middle of the second limiting disk has a second installation through hole. The second limiting disk is combined with the first limiting disk in a manner of partial indentation or partial protrusion. For the chisel with double limiting disks of the present invention, the second limiting disk is combined with the first limiting disk in a manner of partial indentation or partial protrusion, which prolongs the service life of the holding seat and the cutter head. The concave portion of the second limiting disk completely encompasses the supporting portion of the holding seat, so that the coaxiality of the position of the chisel and the holding seat is maximally ensured, and the chisel can maintain the optimal rotary cutting performance during operation.

Description

Technical Field

[0001] The invention belongs to the technical field of road maintenance operation equipment, and in particular relates to a chisel with double limit plates. Background Art

[0002] At present, the shank chisel is used in mechanical equipment for ground maintenance, such as on the milling drum of a road milling machine, a road reclaimer or similar machines; the tip of the chisel is its main working part, which is in direct contact with the road substrate to be planed, so the shank chisel structure plays a key role in the cutting effect of the chisel. However, the shank chisel in the prior art is limited to conventional shapes and component structures. During use, the chisel does not rotate smoothly and the rotation speed is not enough, resulting in eccentric wear, short service life, low utilization rate of wear-resistant materials, and low work efficiency. Summary of the invention

[0003] The purpose of the present invention is to create a chisel with double limit plates of the above type, which is characterized in that the contact area between the limit plates and the retaining seat can be increased, the mutual pressure force can be reduced, and the service life of the chisel and the retaining seat can be extended.

[0004] A chisel with double limit plates comprises a retaining seat and a cutter head mounted on the retaining seat, the cutter head comprising a head and an extension portion arranged on the lower side of the head, the bottom of the head having a head support surface, the upper end surface of the retaining seat having a force-bearing surface, a first limit plate and a second limit plate arranged up and down are installed between the retaining seat and the head, the first limit plate has a first mounting through hole in the middle, the second limit plate has a second mounting through hole in the middle, the second limit plate is combined with the first limit plate in a partially recessed or partially raised manner; the extension portion passes through the first mounting through hole and the second mounting through hole. By using this innovative cutter head installation method, it is beneficial to increase the contact area between the first limiting plate and the second limiting plate, reduce the pressure force between each other and transmitted to the retaining seat, and extend the service life of the chisel and the retaining seat. More importantly, the cutter head as a wearing part can be replaced frequently, while the retaining seat needs to maintain a certain service life. In road operations, the part of the retaining seat in contact with the support surface of the cutter head is very easy to wear under huge pressure and sliding friction. Considering this wear, the part of the retaining seat in contact with the support surface of the cutter head will be lengthened and thickened to extend its service life. The present invention adopts a double limiting plate arranged between the retaining seat and the support surface of the cutter head. The first limiting plate and the second limiting plate are replaced by the first limiting plate or the second limiting plate through material selection (for example, the first limiting plate or the second limiting plate is more easily worn relative to the retaining seat), and the first limiting plate or the second limiting plate slides relative to each other, which also reduces the sliding friction and sliding length of the retaining seat, which also reduces the wear of the retaining seat to a certain extent, prolongs the service life of the retaining seat, and reduces the use cost.

[0005] Preferably, the second limiting disk is combined with the first limiting disk in a locally recessed manner; the lower side of the first limiting disk has a lower surface and a positioning portion, and the positioning portion is an annular protrusion provided at the lower edge of the first mounting through hole; the upper side of the second limiting disk has a force guiding surface and a guiding portion, and the guiding portion is an annular concave surface provided along the upper edge of the second mounting through hole.

[0006] Preferably, the positioning portion of the first limiting disk matches the guiding portion of the second limiting disk.

[0007] Preferably, the central axis L1 of the first mounting through hole coincides with the central axis L2 of the second mounting through hole; the first limiting disk and the second limiting disk can rotate freely around the central axis L1 or L2 relative to each other.

[0008] The first mounting through hole and the second mounting through hole have the same diameter, and the first mounting through hole, the second mounting through hole and the extension portion of the chisel blade match each other.

[0009] Preferably, the upper surface of the first limiting disk is in contact with the head supporting surface of the chisel blade; the lower surface of the first limiting disk is in contact with the force guiding surface of the second limiting disk (which is beneficial to increasing the contact area between the first limiting disk and the second limiting disk, reducing the mutual pressing force, and prolonging the service life of the chisel blade and the holder. The same applies to other contact surfaces). The supporting surface of the second limiting disk is in contact with the force receiving surface of the holder.

[0010] Preferably, an inner concave portion is provided along the second mounting through hole on the lower side of the second limiting disk, and the inner concave portion includes an upper limit surface on the inner side and a transition surface with a slope on the outer side.

[0011] Preferably, the upper end surface of the holder has a supporting portion with an annular protrusion, and the supporting portion is fittingly embedded into the inner concave portion, and there is a gap between the supporting portion and the inner concave portion. In terms of relative movement, the holder is "fixed", so the supporting portion of the holder is also "fixed". The inner concave portion of the second limiting disk constitutes a structure meshing with the supporting portion of the holder to achieve the purpose of maximizing the coaxiality with the position of the holder. The setting of the gap can avoid the problem that the supporting surface and the force receiving surface cannot be in contact due to machining errors. If the supporting surface and the force receiving surface are not in contact, the working pressure on the chisel blade and the chisel blade limiting disk cannot be effectively transmitted to the holder, and the working life of the chisel blade and the chisel blade limiting disk will be greatly affected and it will be damaged quickly under a large impact force. Similarly, the transition surface of the second limiting disk and the guiding surface of the holder are also preferably in a clearance fit state, which can also make the inner concave portion of the second limiting disk completely encompass the supporting portion of the holder. After the chisel blade limiting disk and the holder are separated to a certain extent during work, they can quickly return to the original relative position state and will not get stuck when the limiting disk rotates.

[0012] Preferably, an outer convex portion is provided along the second mounting through hole on the lower side of the second limiting disc, and the upper end surface of the holding seat has a recessed supporting portion. The outer convex portion is fittingly embedded into the supporting portion, and there is a gap between the outer convex portion and the supporting portion.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] For the chisel with double limiting discs of the present invention, the second limiting disc is combined with the first limiting disc in a manner of partial indentation or partial protrusion. By using this innovative tool head mounting method, it is beneficial to increase the contact area between the first limiting disc and the second limiting disc, reduce the mutual and the pressing force transmitted to the holding seat. Part of the wear of the holding seat is replaced by the first limiting disc or the second limiting disc, extending the service life of the holding seat and the tool head; moreover, the inner concave portion of the second limiting disc completely encompasses the supporting portion of the holding seat, thus maximizing the coaxiality of the position of the chisel and the holding seat, and enabling the chisel to maintain the optimal rotational cutting performance during operation. Description of the Drawings

[0015] Figure 1 is a half-sectional view of the chisel with double limiting discs of the present invention mounted in the holding seat;

[0016] Figure 2 is Figure 1 an enlarged view of the partial sectional view in

[0017] Figure 3 is Figure 1 a lateral full sectional view of the combined structure of the first limiting disc and the second limiting disc in

[0018] Figure 4 is Figure 1 an exploded view of the combined structure of the first limiting disc and the second limiting disc in

[0019] Figure 5 is Figure 1 a schematic view of the upper structure of the combined structure of the first limiting disc and the second limiting disc in

[0020] Figure 6 is Figure 1 a schematic view of the bottom structure of the combined structure of the first limiting disc and the second limiting disc in

[0021] Figure 7 is a lateral full sectional view of another embodiment of the present invention. Detailed Embodiments

[0022] Figure 1 、 2The front side view shows a chisel 5 with a double limit disc installed in a holding seat 3. The chisel 5 includes a top 6 made of tungsten carbide-cobalt hard alloy, which is permanently fixed in a blind-hole-shaped molten pool of the chisel head 7 by brazing. The chisel extension 8 extends below the chisel head 7 and is formed by a cylinder with a diameter smaller than that of the chisel head 7. A first limit disc 1 and a second limit disc 2 are sleeved on the first holding handle 8.1 of the chisel extension 8. The upper surface 1.1 of the first limit disc 1 is in close contact with the supporting surface 7.1 of the chisel head 7, while the supporting surface 2.6 of the second limit disc 2 is in close contact with the convex ring surface 3.2 of the holding seat 3. The fastening steel sleeve 4 is usually made of thin steel plate rolled, has a certain elasticity, has an opening, has a suitable length, and is sleeved in the second holding handle 8.2 of the chisel extension 8. A number of internal depressions 4.1 are processed on the surface by stamping and are fitted into the grooves 8.3 of the holding handle. The fastening steel sleeve 4 is pressed into the installation through-hole of the holding seat 3, and the outer side expands and presses tightly in the installation through-hole of the holding seat 3 and maintains fixed contact.

[0023] Figure 2 Enlarged Figure 1 of the partial view therein, where the first limit disc 1, the second limit disc 2, the holding seat 3, and the fastening steel sleeve 4 are shown as semi-sectional views. As Figure 2 shown, in the actual working state, the concave portion 2.7 of the second limit disc 2 constitutes a structure meshing with the supporting portion 3.1 of the holding seat 3. Among them, the upper limit surface 2.4 and the convex ring surface 3.2 are in a clearance fit state, and the clearance value is within 0.4 mm and 2.9 mm. And the transition surface 2.5 and the guiding surface 3.3 are in a clearance fit state, and the supporting surface 2.6 is in contact fit with the stress surface 3.4. The advantage of this is to eliminate the dimensional errors caused by machining. During the working process, it can be considered that the holding seat 3 is relatively stationary, and the first limit disc 1 and the second limit disc 2 rotate around the holding seat 3, that is, the central axes L1 and L2 of the first limit disc 1 and the second limit disc 2 rotate around the central axis L of the holding seat 3.

[0024] Again, as Figure 1 、 2 shown, the supporting portion 3.1 of the holding seat 3 extends from one side of the stress surface 3.4 to form a circular convex platform shape, with the convex ring surface 3.2 as the end surface in the length direction and the guiding surface 3.3 as the end surface in the diameter direction, and forms an installation through-hole around the central axis L of the holding seat 3 for accommodating the fastening steel sleeve 4, the second holding handle 8.2, and the third holding handle of the chisel 5.

[0025] In Figures 2 to 6As can be seen, the first holding handle 8.1 of the extension part 8 of the chisel 5 has a diameter d1, and the dimension range thereof is between 15 mm and 25 mm. The first limiting disc 1 has a mounting through hole 10 with a diameter D1, and the dimension range thereof is between 16 mm and 26 mm; the second limiting disc 2 has a mounting through hole 20 with a diameter D2, and the dimension range thereof is between 16 mm and 26 mm. The first holding handle 8.1 of the extension part 8 of the chisel 5 is installed in the mounting through holes 10 and 20 of the first limiting disc 1 and the second limiting disc 2. The positioning part 1.4 of the first limiting disc 1 and the guiding part 2.2 of the second limiting disc 2 are in an interlocked match. The lower surface 1.5 of the first limiting disc 1 and the force guiding surface 2.1 of the second limiting disc 2 are arranged to be in contact and cooperate. The mounting through hole 10 of the first limiting disc 1 has a central axis L1 and is arranged coaxially with the central axis L2 of the mounting through hole 20 of the second limiting disc 2. The first limiting disc 1 and the second limiting disc 2 can rotate freely around the central axis L1 relative to each other. The concave part 2.7 of the second limiting disc 2 is surrounded by an upper limit surface 2.4 and a transition surface 2.5. Such a design ensures that the chisel 5 maintains the maximum coaxiality with the central axis L of the holder 3 during the working rotation process, improving the service performance and lifespan of the chisel 5, etc.

[0026] The chisel 5 needs to maintain a high-speed rotation in the mounting through hole of the holder 3. Therefore, during the working rotation process, the chisel 5 needs to maintain the maximum coaxiality with the central axis L of the holder 3, which is beneficial to improving the service performance of the chisel 5. Therefore, the first limiting disc 1 and the second limiting disc 2 can also increase the contact area between the limiting disc and the holder, reduce the mutual pressing force, extend the service life of the chisel and the holder, and achieve the beneficial effects of the present invention. Embodiment

[0027] Similar to Embodiment 1, the difference is that an outward convex part 2.7' is provided along the second mounting through hole on the lower side of the second limiting disc. At this time, the upper end surface of the holder has a sunken supporting part, and the outward convex part is embedded into the supporting part in a matching manner, and there is a gap between the outward convex part and the supporting part.

[0028] It should be noted that the drawings of this embodiment all adopt very simplified forms and non-precise ratios, and are only used to conveniently and clearly assist in explaining the embodiments of the present invention.

[0029] Although the embodiments of the present invention have been disclosed as above, it is not limited to only the applications listed in the description and embodiments. It can be fully applied to various fields suitable for the present invention. For those familiar with the field, additional modifications can be easily made. Therefore, without departing from the general concept defined by the claims and the equivalent scope, the present invention is not limited to specific details and the illustrated examples here.

Claims

1. A chisel (5) with double limiting discs, comprising a holding seat (3) and a cutter head mounted on the holding seat (3), the cutter head including a head (7) and an extension part (8) provided on the lower side of the head (7), the bottom of the head (7) having a head bearing surface (7.1), and the upper end surface of the holding seat (3) having a force-receiving surface (3.4), characterized in that , a first limiting disk (1) and a second limiting disk (2) are installed up and down between the holding seat (3) and the head (7). The middle of the first limiting disk (1) has a first mounting through hole (10), and the middle of the second limiting disk (2) has a second mounting through hole (20). The extending part (8) passes through the first mounting through hole (10) and the second mounting through hole (20); The second limiting disk (2) is combined with the first limiting disk (1) in a partially recessed manner. The lower side of the first limiting disk (1) has a lower surface (1.5) and a positioning part (1.4). The positioning part (1.4) is an annular protrusion provided at the lower edge of the first mounting through hole (10). The upper side of the second limiting disk (2) has a force guiding surface (2.1) and a guiding part (2.2). The guiding part (2.2) is an annular concave surface provided along the upper edge of the second mounting through hole (20). The lower surface of the second limiting disk (2) has an annular supporting surface (2.6); The upper surface (1.1) of the first limiting disk (1) is in contact with the head supporting surface (7.1) of the chisel (5). The lower surface (1.5) of the first limiting disk (1) is in contact with the force guiding surface (2.1) of the second limiting disk (2), and the supporting surface (2.6) of the second limiting disk (2) is in contact with the force receiving surface (3.4) of the holding seat (3); An inner concave part (2.7) is provided along the second mounting through hole (20) on the lower side of the second limiting disk (2). The inner concave part (2.7) includes an upper limit surface (2.4) on the inner side and a transition surface (2.5) with a slope on the outer side; The upper end surface of the holding seat (3) has a supporting part (3.1) in the shape of an annular protrusion. The supporting part (3.1) is fitted into the inner concave part (2.7) in a matching manner, and there is a gap between the supporting part (3.1) and the inner concave part (2.7); or An outer convex part (2.7') is provided along the second mounting through hole (20) on the lower side of the second limiting disk (2). The upper end surface of the holding seat (3) has a recessed supporting part. The outer convex part (2.7') is fitted into the supporting part in a matching manner, and there is a gap between the outer convex part (2.7') and the supporting part; The positioning part (1.4) of the first limiting disk (1) is matched with the guiding part (2.2) of the second limiting disk (2); The central axis L1 of the first mounting through hole (10) coincides with the central axis L2 of the second mounting through hole (20). The first limiting disk (1) and the second limiting disk (2) can rotate freely around the central axis L1 or L2 relative to each other.

2. The chisel (5) with double limit discs according to claim 1, characterized in that, The first mounting through hole (10) and the second mounting through hole (20) have the same diameter, and the first mounting through hole (10), the second mounting through hole (20) and the extending part (8) of the chisel (5) are matched with each other.

Images