DUAL-SPINDLE CIRCULAR SAW FOR SAWING WOOD

Abstract

A dual-spindle circular saw (1) for sawing wood (2) with two saw groups (3) is proposed, wherein each saw group (3) comprises a drive (7) having an armature (5) and a stator (6) for rotary driving of a saw spindle (9) which is mounted in a housing (8) and which is connected in a rotationally fixed manner to at least one saw tool (11) comprising at least one exchangeable circular saw blade (10), and wherein the center distance (A) of the saw spindles (9) is adjustable by means of an actuator. In order to create particularly advantageous design conditions, it is proposed that the armature (5) is arranged in a rotationally fixed manner on the saw spindle (9) and the stator (6) is arranged in a rotationally fixed manner in the housing (8) between a fixed bearing (13) and a floating bearing (14) of the saw spindle (9), wherein the saw tool (11) is floatingly mounted on the saw spindle (9).

Claims

1. A dual-spindle circular saw for sawing wood, said saw comprising: two saw groups, wherein each saw group has a drive having an armature and a stator providing rotary driving of a saw spindle that is mounted in a housing and that is connected in a rotationally fixed manner to a saw tool comprising exchangeable circular saw blades, and wherein an actuator provides adjustment of a center distance of the saw spindles, wherein the armature is rotationally fixed on the saw spindle and the stator is rotationally fixed in the housing between a fixed bearing and a floating bearing of the saw spindle, and wherein the saw tool is floatingly mounted on the saw spindle.

2. A dual-spindle circular saw according to claim 1, wherein the saw tool comprises a circular saw blade group interchangeably supported on a tool clamp, wherein the tool clamp is detachably fastened via a quick-change cone to the saw spindle, which has a corresponding counterpart in the form of a conical axle stub.

3. A dual-spindle circular saw according to claim 2, wherein the tool clamp is secured with a screw connection that extends coaxially with an axis of the saw spindle, a head actuating the screw connection is mounted in the tool clamp so as to be freely rotatable but axially secured therein.

4. A dual-spindle circular saw according to claim 1, wherein the armature or the stator of the drive, or both, are liquid-cooled.

5. A dual-spindle circular saw according to claim 1, wherein the armature, the stator, the fixed bearing, and the floating bearing are liquid-cooled.

6. A dual-spindle circular saw according to claim 4, wherein the liquid cooling is provided by a liquid cooling system that is equipped with a temperature control preventing undershooting of a dew point in the housing.

7. A dual-spindle circular saw according to claim 1, wherein the saw spindle is liquid-cooled by a rotary union operatively associated with an end of the saw spindle facing away from the saw tool, a sleeve being connected to the rotary union is inserted into a bore coaxial with an axis of the saw spindle such that a flow channel is formed between the bore wall and sleeve.

8. A dual-spindle circular saw according to claim 1, wherein the stator is inserted into the housing so as to form a flow channel providing liquid cooling of the stator between the stator and the housing, or the housing enclosing the stator has a flow channel providing liquid cooling of the stator.

9. A dual-spindle circular saw according to claim 8, wherein the housing is provided with a jacket tube around an outer circumference thereof, and wherein the flow channel providing liquid cooling of the stator is formed between the jacket tube and the stator.

10. A dual-spindle circular saw according to claim 1, wherein the floating bearings or the fixed bearings are inserted into a bushing supported rotationally fixed in the housing in a bearing block, wherein a flow channel providing liquid cooling of the bearings is formed between the bushing and the bearing block.

11. A dual-spindle circular saw according to claim 7, wherein the flow channel extends helically around an axis of the saw spindle.

12. A dual-spindle circular saw according to claim 1, wherein the floating bearing and the fixed bearing each comprise at least one rolling bearing connected via fluid lines to an oil-air lubrication device.

13. A dual-spindle circular saw according to claim 1, wherein the stator has coils that are formed of shaped wire.

14. A dual-spindle circular saw according to claim 1, wherein the stator has coils with pole ends, and the pole ends of the coils of the stator are guided out of the housing on an end face side or a floating bearing side in an axial direction parallel to an axis of the saw spindle.

15. A dual-spindle circular saw according to claim 2, wherein a screw connection coaxial with an axis of the saw spindle secures the tool clamp in a mounting position.

16. A dual-spindle circular saw according to claim 5, wherein four liquid-cooling circuits cool the armature, the stator, the fixed bearing, and the floating bearing, and temperature control valves provide independent temperature control for each of the cooling circuits.

17. A dual-spindle circular saw according to claim 7, wherein the sleeve is inserted into the bore in an axial direction through the floating bearing, the armature, and the fixed bearing.

18. A dual-spindle circular saw according to claim 8, wherein the housing is provided with a jacket tube around an outer circumference thereof, and wherein the flow channel providing liquid cooling of the stator is formed between the jacket tube and the housing.

19. A dual-spindle circular saw according to claim 1, wherein the floating bearing and the fixed bearing each comprise at least one rolling bearing connected via fluid lines to a central oil-air lubrication device.

20. A dual-spindle circular saw according to claim 8, wherein the flow channel extends helically around an axis of the saw spindle.

Description

BRIEF DESCRIPTION OF THE INVENTION

[0028] In the drawing, the subject matter of the invention is shown by way of example, wherein:

[0029] FIG. 1 shows a front view of a dual-spindle circular saw,

[0030] FIG. 2 shows a saw group of the dual-spindle circular saw in schematic longitudinal section,

[0031] FIG. 3 shows the enlarged and more detailed left section with the fixed bearing of the saw group from FIG. 2, and

[0032] FIG. 4 shows the enlarged and more detailed right section with the floating bearing of the saw group from FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0033] The dual-spindle circular saw 1 for sawing wood 2 comprises two saw groups 3. The saw groups 3 are offset in the cutting direction 4 of the wood 2 to be cut. Each saw group 3 has an electric motor 7, comprising an armature 5 and a stator 6, for a rotary drive of a saw spindle 9 mounted in a housing 8. The saw spindle 9 is connected in a rotationally fixed manner to at least one saw tool 11 comprising at least one replaceable circular saw blade 10. The saw tool 11 and the saw spindle 9 therefore rotate together at the same angular speed when driven. The center distance A of the saw spindles 9 can be adjusted with an actuator not shown in more detail. The lateral offset of the saw tools 11 relative to each other in the direction of the saw spindle axis 12 can also be adjusted with this or another actuator to ensure that the circular saw blades 10 of the two saw tools are precisely aligned with each other and lie in one and the same cutting plane.

[0034] According to the invention, the armature 5 is arranged in a rotationally fixed manner on the saw spindle 9 and the stator 6 is arranged in a rotationally fixed manner in the housing 8 between a fixed bearing 13 and a floating bearing 14 of the saw spindle 9. The saw tool 11 is mounted in cantilever fashion on the saw spindle 9. The saw groups 3 are arranged parallel to the saw spindle axis and with the housing 8 aligned in the same way in a machine frame or the like that is not shown in more detail.

[0035] The saw tool 11 comprises at least one saw blade 10 interchangeably accommodated on a tool clamp 15, optionally two or more saw blades 10, in particular a circular saw blade group. The tool clamp 15 is detachably fastened by means of a quick-change cone 16 in the manner of a steep cone (for example 7/24) to the saw spindle 9, which has a corresponding counterpart in the form of a conical axle stub 17, and is secured in the mounting position by a screw connection 18 coaxial with the saw spindle axis 12. In the exemplary embodiment, the axle stub 17 is a transition piece fitted to the saw spindle end, but it can also be formed directly by the saw spindle. A head 19, a screw or nut head, for actuating the screw connection with a corresponding tool, is freely rotatable but axially secured in the tool clamp 15. For this purpose, the head 19 is equipped with a shoulder 20, which at one end rests against the tool clamp 15 when the screw connection is tightened and is supported against an annular washer 21 when the screw connection is loosened and the tool clamp 15 is pulled off the axle stub 17.

[0036] The drive, in particular electric motor 7, is liquid-cooled. The armature 5, the stator 6, the fixed bearing 13, a group of rolling bearings, and the floating bearing 14 are liquid-cooled. Four cooling circuits, which can be temperature-controlled independently of one another by means of temperature control valves 22, are provided for this purpose. To avoid undershooting of the dew point in the housing, the cooling circuits can be equipped with a temperature control system to which a heater may be assigned in order to be able to control the temperature of the drive even when it is at a standstill.

[0037] For cooling the armature 5 and the inner rings of the fixed bearing 13 and floating bearing 14 via the saw spindle 9, the saw spindle 9 is liquid-cooled via a rotary union 23 associated with the end of the saw spindle 9 facing away from the saw tool. For this purpose, a sleeve 25 connected to the rotary union 23 is inserted into a bore 24 coaxial with the saw spindle axis 12 and extending in the axial direction, preferably via floating bearing, armature and fixed bearing, in such a way that a flow channel 26 is formed between the bore wall and sleeve 25. The stator 6 is inserted into the housing 8 in such a way that a flow channel 26 for liquid cooling of the stator 6 is formed between the stator 6 and the housing 8 or in the housing 8 enclosing the stator 6. In the present exemplary embodiment, the flow channel 26 is provided in the housing 8 between a stator receptacle and a housing shell. Floating bearings and/or fixed bearings are inserted for cooling on the outer circumferential side into a bushing 28 arranged non-rotatably in the housing in a bearing block 27, the flow channel 26 for liquid cooling of the bearings being formed between the bushing 28 and the bearing block 27. The flow channels of the bearing cooling, the armature cooling and the shaft cooling run helically around the saw spindle axis 12.

[0038] For cooling and lubrication of floating bearing 14 and fixed bearing 13, these are each connected to a central oil-air lubrication device 30 via at least one fluid line 29.