The hunchbacked bar of hacksaw frameTechnical field
What the present invention relates to is a kind of hunchbacked bar of hacksaw frame, the cross sectional shape of especially hunchbacked bar.
Background technology
Hacksaw frame supports saw blade with its bow-shaped structural, and so-called bow-shaped structural has front boom and back boom, and the front and back cantilever is connected by hunchbacked bar, between the end end that cantilever connected without hunchbacked bar before and after saw blade was mounted in.The handling of saw blade when the tensioning degree on the saw frame is related to saw in work is related to the accuracy that sawing is cut.Therefore, in order to guarantee enough tensile forces, saw blade should have enough tension force, and the flexural strength of the bigger hunchbacked bar of length is a The key factor relatively wherein.In the past, hunchbacked bar was that solid steel bar bends, and consumptive material is bigger, has produced split type hacksaw frame afterwards, and hunchbacked bar serves as to save material with flat side's steel pipe.As be anticorrosion attractive in appearance with raising, then used steel material passes through electroplating processes usually.As everyone knows, electroplate not only a large amount of loss precious metals but also produce a large amount of pollutions, so people attempt to substitute the steel through electroplating processes with stainless steel.But stainless steel but exists and does bending strength not as the defective of steel, so the tubing in deltiod cross section commonly used can not satisfy the needs of hacksaw frame.
Summary of the invention
To above-mentioned not mesopodium, the present invention is exactly the hunchbacked bar that the hacksaw frame that a kind of stainless steel pipe that satisfies the needed flexural strength of hacksaw frame makes will be provided.
The hunchbacked bar of hacksaw frame provided by the invention; By the stainless steel tube material forming; The cross sectional shape of this stainless steel pipe is the hollow I-shaped that becomes with the tube wall cropping, and wherein the upper wall of the lower wall of hyphen and following hyphen is a hypotenuse on the I-shaped, the inclination of hypotenuse make the hyphen width from two ends gradually in the expansion of perpendicular both sides.
The hunchbacked bar of hacksaw frame provided by the invention serves as with the stainless steel pipe that the I-shaped shape is arranged, and has improved its flexural strength.Especially up and down the hyphen two ends with in tangent connection of hypotenuse of erecting, guaranteed the feasibility of tube forming, the uniformity of pipe thickness and the enough flexural strengths that finally provide.Compared with prior art, the present invention makes with flat side's stainless steel pipe and saves material more with the environmental protection more of the material after the ordinary carbon steel electroplating processes.
In said the both sides hypotenuse at perpendicular two ends with in the angle of perpendicular center line be 30 ° ~ 60 °, so that higher flexural strength to be provided, make the stainless steel material that under the prerequisite that equal tension can be provided, uses still less.
Inferior horn is fillet on the two ends of said hyphen up and down, and perhaps the two ends of hyphen are the circular arcs tangent with last lower wall up and down, to reduce the stress of two ends bending part, further improves its flexural strength.
Description of drawings
Fig. 1 is the sectional view of one embodiment of the invention, among the figure: the 1-hyphen, perpendicular among the 2-, among the a-both sides hypotenuse at perpendicular two ends with in the angle of perpendicular center line, r-hyphen two ends arc radius.
The specific embodiment
1, the hunchbacked bar of a hacksaw frame; Make by stainless steel pipe; The cross section of this back of a bow rod tube material is as shown in Figure 1; Roughly be a hollow I-shaped shape, connect with a tangent circular arc between the lower wall on the two ends of two hyphens 1 up and down, and in perpendicular about in the of 2 the both sides at two ends be connected with said circular arc is tangent with a hypotenuse.I-shaped height 28 mm wherein, wide 12 mm, in perpendicular high 18 mm of wide part, arc radius r 2 mm, hypotenuse with in 45 ° of the angle a of perpendicular center line.
2, the hunchbacked bar of the hacksaw frame of stainless steel pipe making; The cross section shape of this stainless steel tube such as hollow I-shaped; Its up and down on the hyphen two ends lower wall be connected with circular arc with end wall, up and down hyphen with in the perpendicular wall that is connected be hypotenuse, hypotenuse and in erect 30 ° of the angles of center line.
3, as above example, hypotenuse with in 60 ° of the angles of perpendicular center line, hypotenuse with in erect between the two side and also be connected with circular arc.