Band saw

Abstract

A band saw is includes a driving wheel and a driven wheel rotatably provided at a saw housing; an endless saw band made to run around the driving wheel and the driven wheel; and a plurality of saw band guiding devices for directing and guiding cutting edges of the saw band toward a direction of a workpiece to be cut. The saw band guiding devices are constructed to be movable in directions where one of the guiding devices gets closer to and away from another of the guiding devices, wherein each of the saw band guiding devices includes vibrating means for vibrating the saw band in a cutting direction relative to the workpiece. A pressure member holder including a plurality of pressure rollers or a pressure member for pressing a back surface of the saw band is provided in each of the saw band guiding devices.

Claims

1. A band saw comprising: a driving wheel and a driven wheel rotatably provided at a saw housing; an endless saw band that runs around the driving wheel and the driven wheel; and a plurality of saw band guiding devices for directing and guiding cutting edges of the saw band toward a direction of a workpiece to be cut, wherein the saw band guiding devices are movable in directions such that one of the guiding devices moves toward and away from another of the guiding devices, wherein each of the saw band guiding devices comprises a vibrator including a rotating actuator, a cam coupled with and rotated by the rotating actuator, a cam follower in contact with the cam to undergo motion, and a pressure rod coupled with the cam follower and that vibrates the saw band in a cutting direction relative to the workpiece, wherein a pressure member holder comprising a plurality of pressure rollers that press a back surface of the saw band, is provided in each of the saw band guiding devices and is pivoted about a position between two of the plurality of pressure rollers, wherein the pressure member holder is provided to be rockably pivoted on a substantially central portion of a rocking arm coupled with and driven by the pressure rod so as to be capable of rocking in directions towards and away from the back surface of the saw band at each of the saw band guiding devices, and wherein the plurality of rollers are in a free floating state in accordance with an edge of the saw blade.

2. The band saw as recited in claim 1, wherein the saw housing comprises a beam member elongated in a parting direction between the driving wheel and the driven wheel, the saw housing further comprises the driving wheel and the driven wheel independently and rotatably mounted on front surfaces of wheel supporting members provided respectively at one end side and another end side of a rear surface of the beam member, wherein said one of the guiding devices is provided at a tip end side of a guide arm member that projects at a front surface of one of the wheel supporting members that rotatably comprises the driving wheel, and the rotating actuator of the vibrator that vibrates said one of the saw band guiding devices in the cutting direction of the saw band is provided at a proximal end side of the guide arm member, and wherein said another of the saw band guiding devices is provided at a tip end portion of a movable guide arm movable along a guide portion provided at the rear surface of the beam member and the rotating actuator of the vibrator that vibrates said another of the saw band guiding devices in the cutting direction of the saw band is provided at a curved portion in a front-and-rear direction of the guide arm member.

3. The band saw as recited in claim 2, wherein a rotary shaft of the rotating actuator is provided substantially in parallel with a direction in which the saw band runs.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a schematic elevational view of a horizontal band saw according to an example involved in the prior art.

(2) FIG. 2A is an elevational view of a device for guiding a saw band, which includes a vibrating device involved in the prior art.

(3) FIG. 2B is an enlarged side view of the vibrating device, which mainly shows a cam and its accompanying elements in the device for vibrating.

(4) FIG. 3 is an elevational view of a horizontal band saw according to another example involved in the prior art.

(5) FIG. 4 is a perspective view of a horizontal band saw according to an embodiment of the present invention, which mainly shows its wheels, its saw band and its guiding device.

(6) FIG. 5 is a partial side sectional view of the horizontal band saw according to the embodiment of the present invention, which mainly shows the guiding device supported by a beam, a reciprocating motion generation device and a pressure portion.

(7) FIG. 6 is a partial elevational view of the horizontal band saw according to the embodiment of the present invention, which mainly shows the saw band and the pressure portion in contact therewith.

DESCRIPTION OF EMBODIMENTS

(8) Exemplary embodiments of the present invention will be described hereinafter with reference to the appended drawings.

(9) In the description of the embodiments of the present invention with reference to FIG. 4 and subsequent drawings, while a horizontal band saw is exemplified, it could be embodied as a vertical band saw. By the way, to elements serving the same functions as elements in the band saw described above, the same reference signs will be attached, and then redundant descriptions will be omitted.

(10) Referring to FIG. 4, the total construction of the horizontal band saw according to the embodiment of the present invention is similar to the construction of the horizontal band saw 1A shown in FIG. 3. Therefore the description will be given hereinafter only about the construction of a saw housing that exhibits a distinctive construction.

(11) The saw housing 63 in the horizontal band saw according to the embodiment of the present invention is, as with the saw housing 11A as described above, comprised of a beam member 59 elongated in a parting direction between the driving wheel 7 and the driven wheel 9 (the lateral direction in a horizontal band saw; the vertical direction in a vertical band saw), and one of wheel supporting members 65A is unitarily fixed with a rear surface at one end side of the beam member 59. Further, the driving wheel 7 and the driven wheel 9 are rotatably supported by the wheel supporting members 65A,65B.

(12) The wheel supporting member 65A rotatably supporting the driving wheel 7 is provided to be substantially vertical and this wheel supporting member 65A is provided with one of saw band guiding devices 19A for directing and guiding cutting edges of the saw band 15 toward the workpiece W. And, another of the saw band guiding devices 19B, which along with said one of the saw band guiding devices 19A forms a pair, is provided to be movable in directions where it gets closer to and away from said one of the saw band guiding device 19A.

(13) In more detail, the guide rails 67 (see FIG. 5) as a guide portion in the lateral direction are provided at a rear surface and at a central portion of a rear surface of the beam member 59. These guide rails 67 are provided with a guide arm member 69 to be movable. Further, at a tip end portion (lower end portion) of the guide arm member 69 provided is the saw band guiding device 19B. More specifically, the guide arm member 69 is comprised of a cut-direction rear portion side portion (upper side portion) 69A guided by the guide rails 67 and a cut-direction front portion side portion (lower side portion) 69B. And, at a curved portion where the upper side portion 69A is connected with the lower side portion 69B provided is a vibrating means 71 for vibrating the saw band guiding device 19B in a cutting direction of the saw band 15.

(14) In more detail, at the curved portion 69C, a rocking lever 95, a proximal end portion side of which is pivoted on the guide arm 69 to be capable of rocking via a hinge pin 73, is provided, and a cam follower 77 is rotatably provided at a tip end portion side of the rocking lever 75. Further, a rotating actuator 79 such as a motor or such is attached to the curved portion 69C. A rotary shaft 80 of the rotating actuator 79 is provided to be substantially parallel with a direction where the saw band 15 runs, and a cam member 91 such as an eccentric cam for rocking the rocking lever 75 in the cutting direction of the saw band 15 via the cam follower 77 is unitarily provided at this rotary shaft 80.

(15) Further, one end portion (upper end portion) of a pressure rod 83 provided to be capable of reciprocating motion at the lower side portion 69B of the guide arm member 69 is in contact with a pressure portion 75A provided at the rocking lever 75. This pressure rod 83 is steadily urged by an urging means (repulsive member) 84 such as a coil spring or such provided at the lower side portion 69B in a direction where the rod 83 is to be in contact with the pressure portion 75A. Another end portion (lower portion) of the pressure rod 83 is in contact with a tip end portion of a rocking arm 85 (see FIG. 6) provided to be capable of rocking at the saw band guiding device 19B.

(16) In more detail, the saw band guiding device 19B is, as with the prior saw band guiding devices, comprised of a pair of pinching guide members 87 pinching the saw band 15 from both sides. Further, the saw band guiding device 19B is comprised of a pressure member holder 91 comprising a plurality of pressure rollers 89 of a disk-like shape, which press a back surface 15A of the saw band 15, or a pressure member (not shown) in plane contact with the back surface 15A of the saw band 15. And, at the saw band guiding device 19B, a proximal end portion side of the rocking arm 85 is pivoted on a substantially central portion of this rocking arm 85 via a hinge pin 95 to be capable of rocking.

(17) Said one of the saw band guiding device 19A is provided at a tip end side of a guide arm member unit 97 (see FIG. 4) unitarily provided to project from a front surface of the wheel supporting member 65A. Meanwhile, as the construction of the saw band guiding device 19A is similar to the construction of the saw band guiding device 19B, the same reference signs will be attached and thus redundant descriptions will be omitted.

(18) As being already understood, when the rotating actuator 79 of each vibrating means 71 is made to rotate so that the cam member 81 rotates, the pressure rod 83 is put in reciprocating motion via the cam follower 77 and the rocking lever 75. And, when the tip end portion side of the rocking arm 85 is pressed by the pressure rod 83 in a direction where it gets closer to the saw band 15, the pressure member holder 91 is moved via the hinge pin 95 in the same direction and the plurality of pressure rollers 89 or the pressure member provided at the pressure member holder 91 press the back surface 15A of the saw band 15.

(19) Even if the saw band 15, in this case, becomes bowed by cutting resistance in the cutting direction relative to the workpiece W, as the pressure member holder 91 is capable of rocking in response to this bowed state, the plurality of pressure rollers (pressure member) 89 evenly presses the back surface 15 of the saw band 15. In other words, the load on the workpiece by the saw band 15 in the cutting direction is dispersed evenly to the respective pressure rollers (pressure member) 89, thereby reducing load and extending the lifetime of the respective pressure rollers (pressure member) 89.

(20) Further, as being understood from the aforementioned construction, as each vibrating means 71 is in the region below the beam member 59 and is provided within the region at the front side of the wheel supporting members 65A,65B, it can be enabled to improve compactness of the saw housing 63 and as well, when the saw band 15 is to be detached and exchanged from the driving wheel 7 and the driven wheel 9, it does not interfere with the saw band 15 so that the exchange of the saw band 15 is readily carried out.

(21) Further, as the rotating actuator 79 of the vibrating means 71 is provided at the curved portion 69C and the rotary shaft 80 of the rotating actuator 79 is provided to be parallel with the direction where the saw band 15 runs, it is avoided that the rotating actuator 79 projects forward to a considerable extent, thereby improving compactness of the total constitution and safety.

(22) Although the invention has been described above by reference to certain embodiments of the invention, the invention is not limited to the embodiments described above. Modifications and variations of the embodiments described above will occur to those skilled in the art, in light of the above teachings.

INDUSTRIAL APPLICABILITY

(23) A band saw that extends the lifetime of pressure rollers is provided.