Processing machine

Abstract

A machining tool comprises a machine unit including a driven machining tool and a positioning body for contact with a workpiece. The machine unit is movable relative to the positioning body to change the machining depth of the machining tool. A stop element is provided to limit the machining depth. This stop element is slidably guided in a stop guide of the machine unit and can be fixed in the stop guide by means of a clamping device. The clamping device includes a movable clamping wedge that can be driven between the stop element and a counter bearing of the machine unit by means of an actuating element to press the stop element against a contact surface of the stop guide.

Description

[0001] The present invention relates to a processing machine with a machine unit, according to the preamble of claim 1. Such a processing machine is known from document DE 10 2006 061238 A1.

[0002] Such machine tools are used, for example, in the trades for milling, drilling, sawing, and similar tasks. The mobility of the machine unit relative to the workpiece body allows the cutting tool to plunge into the workpiece. The stop element limits the plunge depth by abutting a corresponding stop surface on the workpiece body, an attached accessory, or the workpiece surface.

[0003] A clamping screw can be provided to secure the stop element. This screw sits in the stop guide and its tip presses against the stop element. However, operating a clamping screw is cumbersome and requires, in particular, repositioning the hand, which hinders precise work. Furthermore, achieving a high clamping force requires a correspondingly high manual force applied to the clamping screw.

[0004] DE 10 2006 061 238 A1 discloses a router in which a depth adjustment element designed as a rack and pinion is provided. The adjustment element can be moved by turning an adjusting knob, and a pivotable lever, the actuation of which can cause the adjustment element to be locked in place, serves to fix a set depth.

[0005] DE 100 21 18 B discloses an attachment for an electric hand milling machine in which the milling tool can be secured in the immersed working position by a locking finger.

[0006] The milling machine disclosed in US 5 988 241 A1 has a milling depth stop in which a stop bar is held by pulling together a collar part.

[0007] CN 114311158 A discloses a machining machine with a stop bar that can be clamped in a housing-side receptacle.

[0008] Devices for milling depth adjustment are also disclosed in DE 40 08 224 A1, in DE 101 36 526 A1 and in DE 17 70 357 U.

[0009] It is an object of the invention to provide a machining machine of the type mentioned which enables a more ergonomic change of the machining depth and enables stable clamping of the stop element in the stop guide even with little manual effort.

[0010] The problem is solved by a processing machine with the features of claim 1.

[0011] According to the invention, the clamping device comprises a movable clamping wedge which can be driven between the stop element and a counter bearing of the machine unit by means of an actuating element in order to press the stop element against a contact surface of the stop guide.

[0012] Driving in the clamping wedge requires only a relatively simple and short movement. Compared to a clamping screw, a clamping wedge can also exert a relatively large clamping force, thus counteracting unwanted wear. By varying the wedge angle, the clamping force and adjustment range can be easily adapted to the specific application.

[0013] A clamping wedge within the meaning of this disclosure may have symmetrical and / or flat side surfaces. However, this is not mandatory. The wedge surfaces may also be curved or have sections with different wedge angles. Accordingly, a clamping wedge is to be understood as any component which, due to a local surface inclination, exerts a wedge effect when moving into the space between the stop element and the counter bearing.

[0014] Furthermore, it should be noted that driving the clamping wedge between the stop element and the counter bearing does not necessarily require that the clamping wedge directly act upon the stop element and the counter bearing, although this may be the intended design. Rather, additional transmission elements could be located between the wedge and the stop element and / or the counter bearing.

[0015] Preferably, the clamping wedge is displaceable by moving the actuating element between a clamping position, in which the clamping wedge is wedged between the stop element and the counter bearing, and a release position, in which the wedging is released. Thus, only the actuating element needs to be moved to fix and release the stop element in the stop guide. When moving the clamping wedge between the clamping and release positions, a slight pivoting of the clamping wedge may occur. That is, it can be, but does not have to be, a perfectly linear movement.

[0016] According to the invention, the clamping device comprises a clamping shaft rotatably mounted on the machine unit, with an eccentric section. The clamping shaft is rotatable by means of the actuating element, and the clamping wedge can be actuated by the eccentric section. This allows for a particularly simple conversion of the movement of the actuating element, especially a rotary or pivoting movement, into a movement of the clamping wedge. The actuating element can be directly coupled to the clamping shaft to save installation space. According to one possible embodiment of the invention, the actuating element and the eccentric section are arranged axially offset from each other on the clamping shaft. The eccentric section can be an eccentric cylindrical section or cam that sits on the clamping shaft or is formed integrally with it.

[0017] The actuating element can be a swivel lever fixed to the clamping shaft. Operating a swivel lever is simple and ergonomic, yet it still requires a relatively high actuating force.

[0018] One embodiment of the invention provides that the machine unit has a handle for holding and / or guiding the machining tool, and the pivot lever is arranged in relation to the handle such that it can be operated with a finger, in particular the thumb, of a hand holding the handle. This eliminates the need for the operator to reposition their grip when adjusting the machining depth. Instead, the machining tool can be held and guided continuously, thus preventing incorrect positioning.

[0019] The clamping wedge can have an eccentric recess into which the eccentric section extends. This allows for a particularly simple design. For example, the eccentric recess can be a feedthrough located in the area of ​​the wedge base of the clamping wedge.

[0020] The clamping shaft can be rotatable about a clamping shaft axis that runs parallel to a longitudinal axis of the stop element. Alternatively, the clamping shaft can be rotatable about a clamping shaft axis that runs perpendicular or at an angle to a longitudinal axis of the stop element. Compared to a locking screw, an arrangement consisting of a clamping wedge and clamping shaft offers more design possibilities with regard to positioning on the machine unit.

[0021] The clamping shaft can be rotated by means of the actuating element by at least one dead center of the eccentric section to provide self-locking. The clamped clamping wedge is then secured against unintentional loosening.

[0022] According to a further embodiment of the invention, the distance between the counter bearing and the stop element is variable. This allows the holding force of the clamping device to be adjusted. In this way, manufacturing tolerances can be compensated for in particular.

[0023] The counter bearing can be formed by the tip of an adjusting screw mounted in the machine unit, or it can be acted upon by such a screw tip. An adjusting screw allows for relatively precise adjustment of the distance between the counter bearing and the stop element. A pendulum bearing or similar feature can be arranged at the screw tip, the contact surface of which conforms to the wedge surface. The adjusting screw can be designed as a setscrew and concealed within the machine unit.

[0024] According to a further embodiment of the invention, the stop guide is at least partially prismatic. This results in a force concentration, which increases the reliability of the clamping. The individual surfaces of the partially prismatic stop guide do not necessarily have to be flat, but can also be slightly curved to avoid wear.

[0025] In particular, the stop guide can comprise flat or slightly curved surface sections that form the contact surface. These surface sections can encompass at least a quarter, and preferably at least half, of the stop element. This ensures reliable guidance.

[0026] Another embodiment of the invention provides that the machine unit has a housing, wherein the stop guide is integrated into the housing and / or a receptacle for the clamping wedge is formed in the housing. This is visually appealing and also facilitates cleaning of the machine unit.

[0027] The contact surface can be formed on an insert that is connected to the housing and made of a material with increased strength compared to the housing's base material. For example, the housing can be made of a lightweight metal such as magnesium. The insert can be made of steel or a hard plastic. This allows the weight of the machine unit to be kept low despite a stable clamping connection.

[0028] The actuating element may be designed to lock onto the machine unit in at least one release position and / or one locking position. The release position corresponds to the loose position of the clamping wedge, while the locking position corresponds to the clamping position of the clamping wedge. Thus, when the actuating element is in the release position, the clamping wedge is in the loose position. Conversely, when the actuating element is in the locking position, the clamping wedge is in the clamping position. This locking mechanism prevents unintentional adjustment of the actuating element, for example, due to vibrations. For this locking action, elastic locking lugs can be arranged on the actuating element, which is designed as an operating lever. These lugs can engage corresponding locking projections on the housing of the machine unit.

[0029] Preferably, the processing machine is designed as a router, and the support body is a base plate of the router. The advantages of the invention are particularly evident when using a router. However, a processing machine according to the invention can also be designed as a drilling machine, plunge saw, circular saw with a pendulum guard, or the like.

[0030] The stop element is preferably a stop bar.

[0031] Further developments of the invention can also be found in the dependent claims, the description and the accompanying drawings.

[0032] The invention is described below by way of example with reference to the drawings. Fig. 1 shows a machining machine according to the invention in a perspective view. Fig. 2 shows a clamping device of the in Fig. 1 The machining tool shown is in sectional view, with a clamping wedge of the clamping device in a released position. Fig. 3 shows the clamping device according to Fig. 2 , wherein the clamping wedge is in a clamping position. Fig. 4 shows an actuating element of the clamping device of a machine tool according to the invention in a release position. Fig. 5 shows the actuating element according to Fig. 4 in a fixed position. Fig. 6 shows an alternatively designed clamping wedge of a machining machine according to the invention.

[0033] At the in Fig. 1 The machining machine 11 shown, designed according to an embodiment of the invention, is a router comprising a support body in the form of a base plate 13 and a machine unit 15.

[0034] The base plate 13 has a preferably flat contact surface for positioning the processing machine 11 against the surface of a workpiece and is guided by two column-like guide elements 19, only one of which is Fig. 1 visible, coupled to the machine unit 15. The machine unit 15 has a housing 21 in which a Fig. 1 A non-visible, preferably electric motor for rotatingly driving a tool holder for a milling tool is housed. The coupling of the machine unit 15 to the base plate 13 via the guide elements 19 is designed in a generally known manner such that a linear plunge movement of the machine unit 15 relative to the base plate 13 along the guide elements 19 is possible. The plunge direction is in Fig. 1 Designated 25. To enable the milling tool to plunge into a workpiece, a recess 26 is provided in the base plate 13.

[0035] Depending on the type of workpieces to be machined, a support body with a curved contact surface or with individual support points can be provided instead of the base plate 13 with a flat contact surface.

[0036] As shown, the housing 21 of the machine unit 15 has a first handle section 27, located on the right in the image, and a second handle section 28, located opposite it. Using the two handle sections 27 and 28, a user can grasp the machine unit 15 and guide the processing machine 11 against a workpiece surface by placing the base plate 13 against it. A switch 30 is located on the first handle section 27, by means of which the motor can be activated and deactivated.

[0037] To limit the machining depth to a specific value, i.e., to define the maximum plunge depth of the milling tool, an adjustable depth stop 29 is provided. This includes a stop element 31, which is linearly displaceable within a stop guide 33 of the machine unit 15. In the illustrated embodiment, the stop element 31 is designed as a rod with a longitudinal axis 35. As shown, the longitudinal axis 35 runs parallel to the plunge direction 25. When the stop element 31 abuts the base plate 13 or a component attached to it during the plunge operation, further plunge penetration is prevented, and the user knows that the maximum plunge depth has been reached.

[0038] The maximum machining depth is changed by manually moving the stop element 31 within the stop guide 33. Once the desired machining depth is reached, the stop element 31 is fixed in the stop guide 33 by means of a clamping device 41, as described in more detail below. The clamping device 41 is engaged and disengaged by operating an actuating element 43, which in this case is a pivot lever.

[0039] The in the Figuren 2 and 3 The clamping device 41 shown in a cutaway top view comprises a clamping wedge 45 which is mounted in the housing 21 of the machine unit 15 and between the in Fig. 2 shown solution position and the one in Fig. 3 The clamping wedge 45 is movable in the clamping position shown. In the released position, the clamping wedge 45 rests loosely against the stop element 31. In the clamping position, however, the clamping wedge 45 is driven clampingly between the stop element 31 and a counter bearing 49 of the machine unit 15.

[0040] Specifically, the clamping wedge 45 has two opposing wedge surfaces 50, 51 inclined relative to each other, one of which is in contact with the stop element 31 and the other with the counter bearing 49. In the clamping position, the wedge surface 51 facing the stop element 31 presses the stop element 31 against a contact surface 53 of the stop guide 33. To concentrate the force, the stop guide 33 can be prismatic, at least in sections, with the individual sections of the prismatic surfaces preferably not being flat but slightly curved to prevent excessive wear. In the illustrated embodiment, the stop guide 33 is integrated into the housing 21. Adjacent to the stop guide 33, a recess 55 for receiving the clamping wedge 45 is provided in the housing 21.

[0041] According to an embodiment of the invention not shown, the contact surface 53 is not formed directly on the housing 21, but on an insert made of steel. This increases the stability of the clamping device 41 without having to make the housing 21 itself out of steel.

[0042] The clamping device 41 further comprises a clamping shaft 57, which is rotatably mounted in the housing 21 of the machine unit 15 about a clamping shaft axis 59. An eccentric section 61 is mounted on the clamping shaft 57 and is rotatably slidably received in a passage 63 of the clamping wedge 45. The clamping shaft 57 is therefore located eccentrically with its axis 59 within the passage 63 of the clamping wedge 45, which, for example, has a circular cross-section. Due to the eccentric section 61, the clamping wedge 45 thus moves similarly to a connecting rod when the clamping shaft 57 is rotated.

[0043] The actuating element 43 is arranged axially offset from the eccentric section 61 with respect to the clamping shaft axis 59 and is therefore in Fig. 2 and 3 only shown with dashed lines. It is about a pivot axis 64 between a in Fig. 2 shown swept-out release position and one in Fig. 3 The clamping wedge 45 can be pivoted in the shown pivoted fixed position. Due to a rotationally fixed connection between the actuating element 43 and the clamping shaft 57, the clamping shaft 57 can be rotated by operating the actuating element 43. Accordingly, the clamping wedge 45 can be moved by pivoting the actuating element 43.

[0044] When the actuating element 43 is in the swiveled-out release position, the clamping wedge 45 is in the release position. Conversely, when the actuating element 43 is in the swiveled-in locking position, the clamping wedge 45 is in the clamping position.

[0045] If the clamping device 41 starts from the in Fig. 2 To activate the position shown, the actuating element 43 is manually swung in and the clamping shaft 57 is moved according to Fig. 2 rotated counterclockwise. The clamping wedge 45 is thereby driven between the stop element 31 and the counter bearing 49 due to the rotation of the eccentric section 61, until the in Fig. 3 The clamping position shown is reached. This is preferably only reached after overcoming the dead center of the eccentric section 61, so that the clamping wedge 45 is self-locking in the clamping position. The stop element 31 is accordingly clamped firmly in the stop guide 33 and cannot be moved further.

[0046] To deactivate the clamping device 41, the actuating element 43 is manually swung out and the clamping shaft 57 is moved from the position in Fig. 3 The position shown is rotated clockwise, overcoming the dead center of the eccentric section 61, as shown in the illustration, until the release position is reached again.

[0047] To regulate the clamping force of the clamping device 41, an adjusting screw 90 is provided, which sits in a corresponding receptacle in the housing 21. The adjusting screw 90 can be designed as a setscrew and be rotatable by means of an Allen key. A pendulum bearing, which forms the counter bearing 49, is arranged at the tip of the adjusting screw 90. By turning the adjusting screw 90, the distance of the counter bearing 49 from the stop element 31 is changed. The pendulum-bearing counter bearing 49 adapts to the corresponding wedge surface 50 during the positioning movement of the clamping wedge 45. The clamping force of the clamping device 41 can be adjusted relatively finely by means of the adjusting screw 90.

[0048] The swivel angle of the actuating element 43 between the swiveled-out release position and the swiveled-in locking position can also be smaller or larger than in the Fig. 2 and 3 shown. Fig. 4 and 5 show a variant in which the choice between the in Fig. 4 shown swept-out release position and the in Fig. 5 In the shown swiveled fixed position, the swivel angle is 90°. Preferably, the actuating element 43 is plate-shaped and rests against the housing 21 when it is in the fixed position.

[0049] The pivot axis 64 of the actuating element 43 preferably runs parallel to the clamping shaft axis 59 or coincides with it, as shown. In particular, the pivoting actuating element 43 can be directly connected to the clamping shaft 57. Furthermore, the pivot axis 64 preferably runs parallel to the longitudinal axis 35 of the stop element 31. This is ergonomically advantageous. In particular, when adjusting the machining depth, the user can place both hands on the handles 27, 28 provided for holding and / or guiding the machining center 11. Fig. 1 ) and operate the actuating element 43 with the thumb, while supporting the other fingers on the first handle 27. Repositioning the grip during the operation is not necessary.

[0050] To secure the actuating element 43 against unintentional adjustment, it is provided with two locking lugs 77. Furthermore, a locking projection 79 is arranged on the housing 21, which allows the locking lugs 77 to be selectively engaged. The locking lugs 77 are arranged such that the actuating element 43 can be locked in both the release and locking positions. Since the locking lugs 77 are elastically deformable, the user can pivot the locked actuating element 43 by overcoming the spring force. Locking the actuating element 43 in the release position allows the stop element 31 to move freely. Locking the actuating element 43 in the locking position secures the clamping device 41 against unintentional release, which could otherwise occur, for example, due to vibrations.

[0051] Should the application require that the actuating element 43 be pivoted in a different orientation with respect to the longitudinal axis 35 of the stop element 31, the clamping wedge 45 can be adjusted accordingly in a relatively simple manner. For example, in the case of the Fig. 6 In the clamping wedge 75 shown, the guide 63 is arranged rotated relative to the wedge surfaces 50, 51 such that the clamping shaft axis 59 is skew to the longitudinal axis 35 of the stop element 31. It is understood that, in principle, any orientation is possible by appropriately designing the clamping wedge 75. Therefore, the disclosed clamping device 41 is particularly flexible with regard to its operating geometry.

[0052] The advantages of the disclosed clamping device 41 according to the invention are not only applicable to routers, but also to other machine tools such as drills, plunge saws, or pendulum saws. Due to the clamping wedge 45, 75, a comparatively high clamping force can be generated on the stop element 31 with a moderate manual effort at the actuating element 43. Depending on the design specifications, the actuating element 43 can, in principle, be positioned freely on the machine unit 15. Bezugszeichenliste

[0053] 11 Machining machine 13 Base plate 15 Machine unit 19 Guide element 25 Plunge direction 26 Recess 27 First handle section 28 Second handle section 29 Adjustable depth stop 30 On / off button 31 Stop element 33 Stop guide 35 Longitudinal axis 41 Clamping device 43 Actuating element 45 Clamping wedge 49 Counter bearing 50 Wedge surface 51 Wedge surface 53 Contact surface 55 Clearance 57 Clamping shaft 59 Clamping shaft axis 61 Eccentric section 63 Feedthrough 64 Swivel axis 75 Clamping wedge 77 Detent stud 79 Detent projection 90 Adjusting screw

Claims

1. A machine tool (11) comprising a machine unit (15), which comprises a drivable machining tool, and a contact body (13) provided for direct or indirect contact with a workpiece, wherein the machine unit (15) is movable relative to the contact body (13) in order to change the machining depth of the machining tool and wherein a stop element (31) is provided for limiting the machining depth, which stop element is displaceably guided in a stop guide (33) of the machine unit (15) and can be fixed in the stop guide (33) by means of a clamping apparatus (41), wherein the clamping apparatus (41) comprises a movable clamping wedge (45, 75) which can be driven in between the stop element (31) and a counter bearing (49) of the machine unit (15) by means of an actuation element (43) in order to press the stop element (31) against a contact surface (53) of the stop guide (33), characterized in that the clamping apparatus (41) comprises a clamping shaft (57) which is rotatably supported at the machine unit (15) and which comprises an eccentric section (61), wherein the clamping shaft (57) can be rotated by means of the actuation element (43) and wherein the clamping wedge (45, 75) can be acted on by the eccentric section (61).

2. A machine tool according to claim 1, wherein the clamping wedge (45, 75) can be displaced by a movement of the actuation element (43) between a clamping position, in which said clamping wedge is wedged between the stop element (31) and the counter bearing (49), and a releasing position in which the wedging is released.

3. A machine tool according to claim 1 or 2, wherein the actuation element (43) is a pivot lever rotationally fixedly connected to the clamping shaft (57).

4. A machine tool according to claim 3, wherein the machine unit (15) has a handle (27) for holding and / or guiding the machine tool (11) and the pivot lever is arranged in relation to the handle (27) such that an actuation of the pivot lever with a finger, in particular with the thumb, of a hand located at the handle (27) is made possible.

5. A machine tool according to any one of the preceding claims, wherein the clamping wedge (45, 75) has an eccentric receiver (63) into which the eccentric section (61) extends.

6. A machine tool according to any one of the preceding claims, wherein the clamping shaft (57) is rotatable about a clamping shaft axis (59) which extends in parallel with a longitudinal axis (35) of the stop element (31), or wherein the clamping shaft (57) is rotatable about a clamping shaft axis (59) which extends perpendicular or skewed with respect to a longitudinal axis (35) of the stop element (31).

7. A machine tool according to any one of the preceding claims, wherein the clamping shaft (57) can be rotated beyond at least one dead center of the eccentric section by means of the actuation element (43).

8. A machine tool according to any one of the preceding claims, wherein the spacing of the counter bearing (49) from the stop element (31) is variable.

9. A machine tool according to any one of the preceding claims, wherein the counter bearing (49) is formed by the screw tip of an adjustment screw (90) received in the machine unit (15) or can be acted on by such a screw tip.

10. A machine tool according to any one of the preceding claims, wherein the stop guide (33) is at least sectionally prism-shaped.

11. A machine tool according to any one of the preceding claims, wherein the stop guide (33) comprises planar or slightly curved surface sections which form the contact surface (53).

12. A machine tool according to any one of the preceding claims, wherein the machine unit (15) has a housing (21), and wherein the stop guide (33) is integrated into the housing (21) and / or a receiver (55) for the clamping wedge (45, 75) is formed in the housing (21), in particular wherein the contact surface (53) is formed at an insert part which is connected to the housing (21) and which is composed of a material that has an increased strength compared to a base material of the housing (21).

13. A machine tool according to any one of the preceding claims, wherein the actuation element (43) can be latched to the machine unit (15) at least in a release position and / or in a fixing position.

14. A machine tool according to any one of the preceding claims, wherein the machine tool (11) is configured as a router and the contact body (13) is a base plate of the router.

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