BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates in general to segments for diamond saw blades used for cutting stones or concrete structures and, more particularly, to a structural improvement in such segments for letting users easily attach the segments to steel discs of the saw blades due to silver solders provided on the bottom surfaces of the segments, and allowing the users to easily directly reproduce the abraded saw blades without sending the abraded saw blades to a reproduction factory.

Description of the Prior Art

With reference to Fig. 1, there is shown a typical saw blade used for cutting stones or concrete structures. The typical saw blade is shown to comprise a steel disc whose edge is integrated with a plurality of segments 10 laden with diamond particles. As shown in the drawing, the edge of the steel disc is radially repeatedly slitted at regular intervals, thus to form a plurality of teeth for the segments 10. When integrating the segments 10 with the teeth of the steel disc into the saw blade, the steel disc is heated under the condition that the segments 10 laden with the diamond particles are placed on their

associated teeth of the steel disc with interposition of silver solders 20 between the segments 10 and the teeth. As a result of heating, the silver solders 20 are melted and integrate the teeth of the steel disc and their associated segments 10 into the saw blade. The typical saw blades are noted that there is no problem in substituting an abraded small-diameter saw blade, whose segments have been completely abraded, with new one because of negligible cost of the steel disc of the small- diameter saw blade. However, as cost of the steel disc of a large-diameter saw blade is not negligible, the large-diameter saw blade is not totally changed with new one but the abraded segments are removes from the teeth of the disc and new segments are attached to the disc. That is, when the segments of the large-diameter saw blade have been completely abraded, the expensive large-diameter steel disc of the saw blade is not discarded but reused while reproducing the saw blade by substituting new segments for abraded segments. In order to reproduce and reuse the typical large- diameter saw blade with abraded segments, the abraded saw blade should be sent to a saw blade production factory and processed for removing the abraded segments from the disc and attaching the new segments to the teeth of the disc respectively. However, the above process for reproducing and reusing the abraded saw blade is noted to cause waste of time and waste of cost as the abraded saw blade is not

directly reproduced by a user but sent to the reproduction factory for substituting new segments for the abraded segments. With the above-described point, the typical saw blades have been shipped abroad in such a manner that the small-diameter saw blades are exported in the state of finished blades but the large-diameter saw blades are exported in the state of separated segments and the segments are integrated with steel discs into the saw blades in the importing country.

SUMMARY OF THE INVENTION

It is, therefore, an object of the present invention to provide a saw blade segment with silver solder in which the above problems can be overcome and which includes the silver solder suitable for facilitating substitution of the segments for abraded segments of the saw blade, thus to allow users to easily directly substitute the new segments for the abraded segments of the blade without sending the abraded saw blade to a reproduction factory for reproducing the abraded saw blade and to let the users save time and cost in reproduction and reuse of the abraded saw blade, and which segment with silver solder also removes the typical silver solder injection device from the saw blade production factory, thus to improve the productivity of the saw blades and let the saw blade production process be automated.

In order to accomplish the above object, the segment for saw blade in accordance with the present invention is provided with a silver solder on its bottom surface. The silver solder of the segment may be formed by attaching a silver solder plate to the bottom surface of the segment by means of viscous flux or by providing the segment with a silver solder channel whose both ends or both sides are bent for partially covering the both end surfaces or the both side surfaces of the segment. In addition, the bottom surface of the segment may be provided with a recess for increasing the bonding force between the silver solder plate and the segment. The bonding force between the silver solder plate and the segment may be increased by forming scratches on the bottom surface of the segment. Alternatively, the silver solder of the invention may be formed by immersing the bottom surface of the segment in melted silver solder and by cooling and solidifying the silver solder on the bottom surface of the segment. As a further alternative, the silver solder plate on the bottom surface of the segment may be slightly heated in order to be preliminarily welded to the segment so that the solder plate can be tightly welded to the segment during high temperature sintering of the segment.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and other

advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

Fig. 1 shows a construction of a typical saw blade with segments laden with diamond particles in a partial front view and in a cross sectional view;

Figs. 2A to 2G show saw blade segments with silver solders in accordance with different embodiments of the present invention in bottom perspective views or enlarged bottom perspective views respectively; and

Figs. 3A to 3E show sectional views of segments of Figs. -2A to 2E attached to the teeth of saw blades respectively.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

If described in detail the saw blade segment of the invention, the segment is previously provided with a silver solder on its bottom surface as shown in the drawings and as will be described hereinbelow.

Attachment of the silver solder to the bottom surface of the segment 10 may be most simply achieved by bonding a predetermined thickness of silver solder plate 20 to the bottom surface of the segment 10 by means of viscous flux as shown in Fig. 2A, showing a first embodiment of the invention. In order to use the segments 10 having the silver solder plates 20 simply bonded to the bottom

surfaces of the segments 10, the segments 10 will be simply attached to teeth of a steel disc of a saw blade respectively by a user after removing abraded segments from the teeth of the steel disc and after cleaning the top surfaces of the teeth.

However, the simple bonding of the silver solder plate 20 to the bottom surface of the segment 10 may be suddenly separated from the segment 10 during long time transportation such as for export of the segments 10. In order to overcome the above possible problem of the first embodiment, the segment 10 with the silver solder plate 20 may be slightly heated in order to preliminarily melt the plate 20 and to improve the bonding strength of the plate 20. Alternatively, the silver solder plate 20 may be additionally spot-welded to the bottom surface of the segment 10 as shown in Fig. 2F. As shown in Fig. 2B showing another embodiment of the invention, the bottom surface of the segment 10 may be provided with a recess 12 for tightly fitting the silver solder plate 20 therein such that the plate 20 protrudes out of the bottom surface of the segment 10. The segment 10 with the recess 12 prevents possible separation of the plate 20 from the segment 10. In accordance with a third embodiment of Fig. 2C, the bonding force of the viscous flux between the plate 20 and the segment 10 is increased by forming a plurality of scratches 14 on the bottom surface of the segment 10. The scratches 14 enlarges the bonding area

of the bottom surface of the segment 10 and increases the bonding force of the flux. Of course, it should be understood that the scratches 14 may be provided on the bonding surface of the silver solder plate 20 instead of the bottom surface of the segment 10.

However, forming of the recess 12 or the scratches 14 on the bottom surface of the segment 10 may be not profitable in view of productivity of the segments 10 as the process for production of the segments 10 should include additional steps for forming the recess 12 or the scratches 14 on the bottom surface of each segment 10. The above problem of the above embodiments may be overcome by use of silver solder channels 20A and 20B as shown in Figs. 2D and 2E, which channels 20A and 20B are suitable for increasing the bonding force between the channels 20A and 20B and the segments 10 when bonding the channels to the segments using the viscous flux. In the embodiment of Fig. 2D, the silver solder channel 20A is bent at its both ends and partially covers the both end surfaces of the segment 10 so that the bonded state of the channel 20A on the bottom surface of the segment 10 is increased. In the embodiment of Fig. 2E, the silver solder channel 20B is bent at its both sides and partially covers the both side surfaces of the segment 10 so that the bonded state of the channel 20B on the bottom surface of the segment 10 is increased. The embodiments using the silver solder channels 20A and 20B prevent sudden separation of the

silver solders from the segments 10 without forming recess 12 or scratches 14 on the bottom surfaces of the segments 10. A collateral advantage expected by use of the silver solder channels 20A and 20B is resided in that the bent portions of the channels 20A and 20B are melted and become reinforcing beads 20a and 20b respectively as shown in Figs. 3D and 3E when welding the segments 10 to the teeth of the steel disc. The beads 20a and 20b increase the attaching force between the segments 10 and the teeth of the steel disc.

Alternatively, the silver solders of the segments 10 of the invention may be formed by immersing the bottom surface of the segment in melted silver solder and by solidifying the silver solder on the bottom surface of the segment. As a further alternative, the silver solders of the segments 10 may be formed by applying liquid silver paste on the bottom surface of each segment 10 and by solidifying the silver paste on the bottom surface of the segment 10. In the present invention, the bonding force between the silver solder plates and the segments may be increased by forming the recesses or scratches on the bottom surfaces of the segments or on the bonding surfaces of the silver solder plates as described above. Additionally, the silver solder may be formed on the bottom surface of the segment 10 by use of a silver solder plate 20 of the cap type as shown in Fig. 2G. In order for providing the

scratching effect for the bottom surfaces of the segments 10 or for the bonding surfaces of the silver solder plates 20 of the invention, the bottom surfaces of the segments 10 or the bonding surfaces of the silver solder plates 20 may be subjected to surface machining through a sand blasting using a sand blasting machine, a grinding using a grinder and a shot blasting.

As described above, the saw blade segment with silver solder according to the present invention lets user easily attach the segment to a steel disc of the saw blade due to the silver solder provided on the bottom surface of the segment, and allows the user to easily directly reproduce the abraded saw blade. The saw blade segment, therefore, lets the expensive steel disc of a large-diameter saw blade be easily reused so that the segment provides economical advantage for the users. As the segment is provided with the silver solder on its bottom surface, the user easily directly attaches the segment to the steel disc and reproduce the abraded saw blade without sending the abraded saw blade to a reproduction factory. Therefore, the user saves time and cost in reproducing the abraded saw blade. Furthermore, as the segments with silver solders of the invention can be simply attached to the teeth of the steel disc, the user does not need to cut the silver solder one by one when attaching the segments to the steel disc. Hence, the segment saves silver solder and simplifies the process for attaching the segment to

the steel disc and readily prevents bad quality of the saw blade. As the silver solder is tightly attached to the segment, the silver solder is scarcely suddenly separated from the segment during treatment and transportation of the segments. Another advantage of the segment of the invention is resided in that the segment lets the saw blade production process be automated.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.