WO2008080460A1

WO2008080460A1 - Device and method for the machine processing of a material

Info

Publication number: WO2008080460A1
Application number: PCT/EP2007/010154
Authority: WO
Inventors: Kuno Winkelheide
Original assignee: Brinkmann Gmbh
Priority date: 2006-12-21
Filing date: 2007-11-22
Publication date: 2008-07-10
Also published as: DE102006060764A1

Abstract

The invention relates to a device (100) for the machine processing of a material. The device (100) comprises a fixed stator (110) and a rotatable rotor (120). The rotatable rotor (120) is arranged around the fixed stator (110). The device (100) further comprises a machining tool (130) which is mechanically coupled to the rotor (120).

Description

Apparatus and method for abspanenden editing a

material

description

The present invention relates to an apparatus and a method for abspanenden processing of a material, as can be used for example in wood and metal processing.

In woodworking and metalworking, a lot of chip-removing tools are currently being used. For example, in the manufacture of components for the automotive industry are many tools for metal processing, such as drills, cutters, grinding heads, etc. used. Even in the woodworking industry, such as furniture manufacturers, many tools such as planers, cutting tools, buffing wheels, etc. are used. These tools are currently being picked or clamped in a chuck during wood or metal cutting, and rotated by a motor. The motors used are so-called internal rotors, i. they have a rotor or a spindle which is rotatably mounted, and a stator which is fixed in a cage around the spindle. The principle of the cutting tool, which is driven by an internal rotor, is known from many fields. For example, the field of application of these tools ranges from household use, such as drills or cutting wheels, to heavier industrial tools.

Especially the tools used in the industry, which are subject to much higher loads, since they are mostly operated permanently and also have to meet higher demands on precision and steadfastness are For example, used milling tools in which permanently a milling tool is attached to the engine and rotates, for example, with 6000 rpm. Other cutting tools, eg. As grinding heads and drills, are repeatedly loaded in a so-called tool spindle, each tool requires an individual optimized speed to meet the corresponding requirements for precision and steadfastness.

For example, in some, mostly industrial applications, but also occasionally in domestic applications, it is necessary to use heavier tools in confined spaces. To drill, for example, around the corner or from below, appropriate tools are being built especially in the industrial sector, which redirect a rotational power through belts or bevel gears. Two such tools are shown in Figs. 5a and 5b. Fig. 5a shows an angle drill 500 which allows drilling in four directions around the corner. The angle drill comprises a cylindrical central part 510, in which a spindle and a deflection gear is located. The drive takes place via a main spindle 520, which drives the four drills 530 to 533. All four drill bits 530 to 533 rotate simultaneously, but only a single drill is used for drilling, depending on the orientation. The angle drill 500 is also referred to as Vierachsaggregat.

Fig. 5b shows a drill 550 for industrial use intended to drill a workpiece from below. It is also spoken in connection with such drills 550 from underfloor drilling. The drilling machine 550 shown in FIG. 5b is driven by a main spindle 560. Inside the drill 550, the rotational energy delivered through the main spindle 560 is deflected via a gear, and finally the drill 570 is driven therewith. To have such a translation To illustrate gear, is shown in FIG. 6 is a schematic cross section 600 of such a transmission.

FIG. 6 shows a cross-section 600 through a transfer gear through an underfloor unit. Fig. 6 shows a

Main spindle 610, which drives the axes 620, 630 and 640.

At the ends of the main spindle 610, as well as the axes 620,

630 and 640, there are so-called bevel gears that the

Redirecting the rotary motion to the different axes. The drive shaft 640 ultimately drives via a bevel gear to the actual drill 650, which may optionally be clamped in a drill chuck 660.

FIGS. 5a, 5b and 6 make it clear that the use of internal-rotor motors involves the problem that such lossy transmission and deflection transmissions must be used. Due to the design, it is not possible to use internal rotor motors of the desired power without the lossy conversion gear.

Internal rotor motors, such as synchronous motors, have an inner rotor which is rotatably mounted, and which consists of a spindle, on which magnets are usually glued. The glued magnets have the disadvantage that in operation, ie with a rotating spindle, the centrifugal force of the bond counteracts, ie that the magnets can solve. Accordingly, care should be taken in the manufacture of a spindle that the bond can withstand appropriate loads. At higher centrifugal forces bandages, such as a sleeve or wrapping threads, which are in turn fixed with lacquer / adhesive, applied costly. Around the rotor there is a locked cage or winding package in which a magnetic field is generated by the coils, ie windings, by means of which the rotor is driven. In addition to the large design, internal rotor motors have the disadvantage that in the outboard stator, ie the cage surrounding the spindle, a coil for generating the exciter field must be wound. The winding of the exciting coils into the so-called grooves is technically complex and time-consuming.

Internal rotor motors can be realized both as synchronous and asynchronous machines. They are currently used for chipping materials and are used to drive drills, cutters, grinders, etc. FIGS. 7a to 7c show some chipping tools used. The milling tools shown in Fig. 7a to 7c, are intended to be plugged onto a shaft of a drill or so-called milling motor. In this case, all three tools on a carrier material which receives the actual tool blades. The carrier material is then slipped onto a corresponding shaft and fixed so that it is then ready for chipping processing, e.g. can be used by metal.

In order to produce a clean milling pattern or clean chip removal, each milling / machining tool requires a certain level of speed. In order to achieve a speed level for optimum chip removal, this speed is generated partly directly or through translations, such as belt drives. Standard electric motors, such as the asynchronous internal rotor motors, for example, can be operated at a fixed speed, for example, the 2-pole three-phase asynchronous motor at a mains frequency of 50 Hz, a rated speed of 2930 rpm, for example, so that translations to speeds of, for example, 4500 or 6000 rpm can be realized , The respective speed after the translation depends on the requirements of the respective tools or on the associated specifications, which are specified by the tool manufacturer. Of course, an optimal speed can also be generated via an electronic system, such as a frequency converter with a three-phase asynchronous motor. Furthermore, external rotor motors are known from the prior art, which are preferably used in the fan technology. External rotor motors can be realized in both synchronous and asynchronous motor technology. FIGS. 8a and 8b show a typical fan motor realized as an external rotor. 8a shows an image of a stationary stator, wherein it can be seen that in this motor variant, the winding is on the stationary stator FIG. 8a. Fig. 8b shows an associated rotor, which is attached to the fixed stator. It can be seen that there are no windings in the rotor shown in FIG. 8b.

Further, drum motors are known in the conventional art, such as e.g. in E. Kretzschmar, "Drum Motors RL 072 / RL 110", http://www.e-kretzschmar.de/pdf/RL072- RL110. pdf is read.

It is the object of the present invention to provide an improved concept for chipping materials that is more efficient, less expensive, and achievable in a smaller space.

This object is achieved by a device according to claim 1 and a method according to claim 6.

The present invention provides a device for machining a material having a fixed stator and a rotatable rotor. The rotatable rotor is arranged around the stationary stator. The device further comprises a chipping tool, which is mechanically coupled to the rotor.

The present invention further provides a method of machining a material comprising a step of mechanically copying a chipping tool a rotor. Further, the method of machining a material includes a step of locking a stator and a step of rotating the rotor around the stator.

The gist of the present invention is to provide chipping tools, e.g. in wood, plastics, and metal processing, to implement using an external rotor motor. Embodiments of the present invention offer the advantage that, compared to devices for chipping processing from the prior art, about two-thirds of weight, cost and volume can be saved, wherein embodiments of the present invention have a comparable performance.

A great advantage, for example, in the arrangement of tool blades on an external rotor is in the smaller design. In connection with the synchronous engine technology, about two-thirds of the volume can be saved here, with embodiments of the present invention being more versatile and, moreover, mostly without translation or conversion gears.

In the construction volume of the carrier material of the external rotor, in which, for example, milling or tool blades can be integrated, the motor can be installed with the same. There is no additional space for the engine needed. This results in the already mentioned advantages of weight, space and cost savings.

An external rotor motor can be built significantly cheaper compared to a standard three-phase asynchronous motor, which is realized as an internal rotor. The windings are machined in seconds because the centrally arranged stator is much more accessible than the cage-like stator of an internal rotor. The windings can be machined similar to the windings of a hand drill. be applied, wherein during production a considerable time and cost savings can be realized.

Embodiments of the present invention will be explained in more detail with reference to the accompanying figures. Show it:

1 shows an embodiment of a device according to the invention for abspanenden processing of a material;

FIG. 2 shows a schematic illustration of an embodiment of a device according to the invention for machining a material by chipping; FIG.

Fig. 3 shows an embodiment of a modified

External rotor, with a milling or machining tool;

4 shows an embodiment of a Zerspaners.

FIGS. 5a and 5b drill devices according to the prior art;

Fig. 6 is a schematic representation of a conversion or transmission gear, according to the prior art;

Fig. 7a-c cutting tools according to the prior art; and

Fig. 8a and b Typical conventional fan motors.

Fig. 1 shows a device 100 for abspanenden processing of a material. The device comprises a fixed stator 110 and a rotatable rotor 120. The rotatable rotor 120 is thereby around the fixed stator 110 arranged around. Further, a chipping tool 130 is attached to the rotatable rotor 120, which is exemplified in FIG. 1 as a drill. The chipping tool 130 is mechanically coupled to the rotatable rotor 120. By way of example, FIG. 1 shows a drill as a chipping tool 130, in principle any chipping tools are conceivable, for example milling cutters, grinding heads, grinding wheels, planers, buffing wheels, etc.

The fixed stator 110 forms with the rotatable rotor 120 an external rotor motor, which can be realized both as a synchronous motor and as an asynchronous motor. Furthermore, the device according to the invention can be used flexibly, i. Both underfloor drilling units and differently oriented drilling and processing units can be realized.

For better illustration, Fig. 2 shows a schematic embodiment of a device according to the invention for chipping processing. Fig. 2 shows a rotating external rotor 210 are mounted on the cutting tools 220. In the embodiment shown in Fig. 2 are on the inside of the outer rotor 210 glued magnets 230. In the middle of the arrangement shown in Fig. 2 is the stator 240, which is held for fixing ü- about a shaft. The stator 240 further has grooves 250, in which an electrical winding for generating the exciter field can be introduced.

2, embodiments of the present invention have the advantage that permanent magnets, as shown in FIG. This results in the advantage that the adhesives to be used need not counteract the centrifugal force, as is the case with internal rotors. Fig. 3 shows a further embodiment of an external rotor according to the invention. FIG. 3 shows a milling tool 300 which, in other embodiments of the present invention, may also be realized as any other chip removing machining tool. The milling tool 300 is mounted in the exemplary embodiment, which is shown in FIG. 3, on a carrier material 310, which simultaneously represents the actual external rotor. The carrier material 310 may also carry any other chipping tools. In the opening 320, which is located in the center of rotation of the arrangement in Fig. 3, a fixed shaft with the stator and for fixing the motor is introduced. The milling tool 300 shown in FIG. 3, which is realized as a chipper, could also be mounted rotatably mounted around the stator 240 from FIG. 2.

4 shows a further embodiment of a device according to the invention for machining a material. FIG. 4 initially shows, at the bottom, an external rotor 400 onto which a tool 410 can be applied. In the embodiment shown in FIG. 4, the tool 410, which is realized in the embodiment considered here as a milling tool, is mounted by screws 420 on the external rotor. The screw connection 420 offers the advantage that different tools 410 can be mounted on the same external rotor.

Embodiments of the present invention offer the advantage that chipping tools can be realized in a significantly reduced space. The concomitant saving of material is likewise reflected directly in a cost advantage in the production costs of abrading devices according to the invention.

Another advantage of the present invention results from the fact that tools with lower volume and weight can be realized, which increases their portability, and thus the range of usability significantly expanded, for example, in a small space. Furthermore, the efficiency of the chipping processing in the manufacture of products by embodiments of the present invention is significantly increased, since now can be dispensed with in many cases lossy reversing gear and translations.

The manufacturing process of embodiments according to the invention itself can be realized more efficiently and cost-effectively, since external rotor motors are used which have windings on the stationary rotor situated in the center of rotation. The centrically located stator is much more cost-effective to access, as compared to an outboard stator of an internal rotor motor. Furthermore, external rotor motors offer the advantage that permanent magnets can be mounted on the inside of the external rotor, so that a risk of detachment is already contained by the geometry of the external rotor motor per se.

Three-phase asynchronous motors (DASM) are used as "standard machines" wherever something needs to be rotated or moved: A DASM always generates a magnetic field on the rotor, which requires external energy, ie the stator induces this magnetic field on the rotor For synchronous motors, permanent magnets (permanent magnets) are not used In the case of the synchronous motors, magnets are glued to the circumference of the rotor In the case of the DASM, grooves are milled into the rotor in which so-called short-circuit windings, eg Aluminum, cast in, and afterwards re-planed, and at DASM the speed fluctuates and depends on the load.

For example, a 2-pole DASM with 1.5kW rated power typically has a rated speed of 2830upm at a mains frequency of 50Hz. At idle, the engine turns approximately synchronously with 3000upm. This means that the motor has a speed difference of 170upm between 0 and 100% load (here 1,5kW). There is talk of a relative slip of 5.6% here. The smaller a DASM in its design and thus performance, the greater the slip and thus the speed reduction at nominal operation. The reduced speed also adversely affects the circumferential speed of a milling tool and thus also the surface quality of a machined material.

In synchronous motors, the excitation is generated by means of magnets, it is for this no energy as the DASM needed. Thus, the use of synchronous motors enables energy savings. Synchronous motors have, as the name already expressed, no speed change under load. Regardless of whether the synchronous motor is idling, with its nominal power or overload, typically up to a factor of 3, the synchronous motor runs constantly at its speed. This means that z. B. in a milling process, the peripheral speed of a tool remains the same, so that the surface quality of a machined material is always the same. Since there is no slippage, the usable power is also 5.6% higher in relation to the above example. Embodiments of the present invention thus offer the advantage that a more efficient and more precise processing is possible because due to the applicability of synchronous motors, the speed of the tools kept constant, avoiding slippage and thus a higher surface quality can be achieved.

A further advantage is that embodiments of the present invention make the smaller design and the lower weight of a synchronous motor usable for the same power. Since there is no fall in speed and a lower energy requirement, there are further advantages. The combination of an external rotor and synchronous motor with The interchangeable "milling rotor, (rotor and tool are one)" brings these advantages to advantage.

LIST OF REFERENCE NUMBERS

100 Device for machining a material

110 stationary stator

120 rotatable rotor

130 chipping tool

210 external rotor 220 cutting tools

230 glued magnets

240 stator

250 grooves

300 milling tool 310 carrier material / external rotor

320 opening in the center of rotation

400 external rotor

410 tool

420 screw connection 500 angle drill

510 cylindrical middle part

520 main spindle

530 to 533 drills

550 drilling machine 560 main spindle

570 drills

600 gear cross section

610 main spindle

620 drive shaft 630 drive shaft

640 drive shaft

650 drills

660 drill chuck

Claims

claims

1. Devices (100) for chipping a material, having the following features:

a fixed stator (110);

a rotatable rotor (120), wherein the rotor (120) is disposed around the fixed stator (110); and

a chipping tool (130) mechanically coupled to the rotor (120).

2. Device (100) according to claim 1, wherein the chipping tool (130) as a drill, a milling cutter, a grinding head, a grinding wheel, a planer or a buffing wheel is formed.

3. Device (100) according to one of claims 1 or 2, wherein the rotor (120) and the stator (110) form an external rotor motor, which is designed as a synchronous motor.

4. Device (100) according to one of claims 1 or 2, wherein the rotor (120) and the stator (110) form an external rotor motor, which is designed as an asynchronous motor.

5. Device (100) according to one of claims 1 to 4, wherein the chipping tool (130) is designed as a drill and the rotor (120) and the stator (110) are arranged such that the device acts as a bottom drill ,

6. Method for machining a material, with the following steps: mechanically coupling a chipping tool to a rotor (120);

Locking a stator (110); and

Rotating the rotor (120) around the stator (110).