JP3626780B2 - Electric hand-held tool machine - Google Patents

Description

[0001]
[Industrial application fields]
The present invention is an electric hand-held tool machine such as an angle grinder, hand-held circular saw and the like, in which a rotary tool such as a separating or polishing disk, circular saw plate and the like can be tightened. A mechanical casing with a bearing flange for rotatably receiving a protruding working spindle, and a cylindrical clamping neck formed on the outside of the bearing flange for inserting a protective hood for a rotating tool, And a locking device for fixing the protective hood on the tightening neck, the locking device pivoting on the support flange and a locking means for engaging the tightening collar of the protective hood placed on the tightening neck. The present invention relates to a type having a hand lever which is supported and moves the coupling means to the working position and the non-working position.
[0002]
[Prior art]
In a known hand-held tool machine (German Patent 39 13 898), which is conceived as an angle grinding machine of this type, the locking means of the locking device are on the one hand part of the tightening collar of the protective hood. On the other hand, a ridge that is attached to the hand lever and that projects into the shape of the depression under the action of a compression spring that is loaded on the hand lever. Have. The hand lever can be pivoted against the spring force to rotate the protective hood over the tightening neck in the desired position, thereby allowing the ridge to be removed from the recess. Thereafter, the protective hood is rotated without any problem and brought to a desired position so that the raised portion can be locked into the recess again when the hand lever is released. The sides of the ridges and the sides of the depressions are compatible with each other and ensure that there is no play when locked. Adjustment of the rotation of the protective hood can therefore be done without tools in separate angle steps which are fixedly fixed to each other by the recess spacing.
[0003]
【The invention's effect】
On the other hand, the electric hand-held tool machine according to the present invention having the characteristics described in claim 1 is protected because the position of the protective hood on the tightening neck of the hand-held tool machine can be rotated steplessly over 360 °. It has the advantage that there is no need to specially form a hood fastening collar. All locking devices are exclusively attached to the bearing shield or bearing flange of the hand-held tool machine. For this reason, the protective hood can be manufactured very advantageously in terms of cost, and the storage of the protective hood is very convenient for the user because of the disk-shaped rotary tool having various diameters. All the protective hoods can be fastened and fastened in the same manner using a locking device provided on the hand-held tool machine. The disengagement and closing of the locking device can be operated well with very little force by only actuating the hand lever, as is the case with known hand-held tool machines. Regardless of the rotational position of the protective hood, the hand lever is always in a position that is advantageous and unobstructed for action by the hand-held tool machine.
[0004]
Overall, the locking device of the hand-held tool machine has a structurally simple construction and can therefore be manufactured in a cost-effective manner. The locking device is self-adjusting and is therefore not sensitive to manufacturing tolerances of the protective hood. The locking function is particularly reliably performed by self-amplification.
[0005]
Advantageous further configurations of the hand-held tool machine described in claim 1 are possible by the means described below.
[0006]
The automatic adjustment of the locking device can be achieved particularly reliably by making the clamping member elastically deformable, for example from a solid rubber body or from a steel strip as a hollow cylinder. When tightening in a stationary manner, the tightening member is elastically deformed in a large range, so that no post adjustment of the locking device is necessary even if the tolerance is large.
[0007]
【Example】
The invention will now be described in detail on the basis of an embodiment illustrated in the drawings.
[0008]
An angle grinding machine, which is shown in section in the drawing as an example of an electric hand-held tool machine with a disk-like rotary tool, has an electric motor with a machine casing 10 for receiving a transmission, and the machine casing 10 Is formed as a head portion 101 made of plastic in the front region, and the head portion 101 supports a ring-shaped support flange 11 made of plastic (FIG. 3). A ball bearing 12 is received in the bearing flange 11, and protrudes from the bearing flange 11 in the bearing 12 to receive a disk-shaped rotating tool such as a separation disk or a polishing disk in a non-rotatable manner. A work spindle 13 is supported, and the work spindle 13 is driven by an electric motor via a transmission. A cylindrical tightening neck portion 14 for fixing the protective hood 15 is formed outside the support flange 11. The protective hood 15 is fitted on the tightening neck portion 14 by a ring-shaped tightening collar 16 formed integrally with the protective hood 15, and the mechanical casing 10 is locked by a lock device 17 at a desired rotational position of the tightening neck portion 14. It is fixed relatively immobile.
[0009]
The locking device 18 has two tightening members 18, one eccentric cam (19) disposed therebetween, and a hand lever 20 that is non-rotatably coupled to the eccentric cam 19. The clamping member 18 and the eccentric cam 19 are arranged in a receiving chamber 21 of the bearing flange 11 extending to the tightening neck 14. The tightening neck 14 has a through-wall hole 22 in the region of the receiving chamber 21. The back wall 211 of the receiving chamber 21 located on the opposite side of the tightening neck 14 and facing the through-wall hole 22 is configured to be flat and perpendicular to the diameter line of the tightening neck 14 to the support neck 11. It extends and forms a single string for the circular tightening neck 14. A spring clasp 23 is fixed to the back wall 211 of the receiving chamber 21 by a U-shaped clasp 231. The clasp ends or spring ends 232 and 233 of the spring clasp 23 surround both clamping members 18 with their outer sides opposite to each other and press the clamping members 18 toward the eccentric cam 19. . In this example, the tightening member 18 is configured as a roller or a roller and can be elastically deformed. The clamping member 18 can be manufactured from a solid rubber body or can be manufactured as a hollow cylinder made of strip steel.
[0010]
The eccentric cam 19 is a prism-like part having a substantially square cross section and a chamfered edge, and is formed in the bearing flange 11 by two coaxial end face journals 191 and 192 projecting from the end face. The camshaft is rotatably supported (FIG. 3), and the camshaft extends parallel to the rear wall 211 of the receiving chamber 21 and the axis of the work spindle 13. The receiving chamber 21 is formed so as to open toward the end face of the bearing flange 11 and is closed by the cover 24, so that both end side journals 191 and 192 of the eccentric cam 19 are on the other hand in the hole 25 of the cover 24. And on the other hand is receivable in the blind hole 26 in the bottom 212 of the receiving chamber 21. The hand lever 20 is non-rotatably coupled to the eccentric cam 19 in the vicinity of the bottom 212 of the receiving chamber 21, and more preferably the eccentric cam 19 is formed as one piece on the hand lever 20. Further, the non-rotatable coupling between the hand lever 20 and the eccentric cam 19 is a lock position of the lock device 17, and when the hand lever 20 is in contact with the tightening neck portion 14 (FIG. 2), a square shape is obtained. The eccentric cam has a larger transverse cross-sectional axis oriented parallel to the rear wall 211 of the receiving chamber 21, and thus is aligned with the moving direction of the clamping member 18, and When the hand lever 20, which is the release position, is pivoted from the tightening neck portion 14 (FIG. 1), the smaller transverse axis of the eccentric cam 19 is aligned with the sliding direction of the tightening body 18. Yes.
[0011]
The mode of operation of the locking device 17 is performed as follows.
[0012]
In the unlocked position of the locking device 17 shown in FIG. 1, the hand lever 20 is pivoted away from the tightening neck 14 so that the eccentric cam 19 is oriented radially by its longer transverse section axis. Has been. The spring clasp 23 presses both tightening members 18 on the wide side of the eccentric cam by both spring ends 232 and 233. In this release position of the locking device 17, the protective hood 15 is fitted on or removed from the tightening neck 14 in the axial direction by its tightening collar 16, and is disposed circumferentially on the tightening neck 14. Is arbitrarily rotatable until the desired position is achieved. Thereafter, the hand lever 20 is pivoted in the direction of the arrow 27 so that the hand lever 20 is completely brought into contact with the tightening neck 14 and protruded so as not to be obstructed by the angle polishing machine during the operation. The eccentric cam 19 is rotated counterclockwise in FIG. 1 by this pivoting movement of the hand lever 20 so that the eccentric cam 19 can occupy the position shown in FIG. 2 in the locked position. The smaller transverse axis of the cam 19 is oriented in the radial direction and the clamping member 18 is supported on the narrow side of the eccentric cam 19. Therefore, when the eccentric cam 19 rotates, the tightening member 18 moves along the clasp U-shaped portion 231 of the spring clasp 23 in the opposite movement direction on the string with respect to the tightening neck portion 14, and penetrates the wall through hole 22. Then, it enters the tightening neck portion 14 and is pressed against the cylindrical inner surface of the tightening collar 16 of the protective hood 15. The clamping member 18 is deformed due to its elasticity, thereby compensating for tolerances, so that no post adjustment of the locking device 17 is necessary.
[0013]
In order to disengage the locking device 17 in order to rotate the protective hood 15 on the tightening neck 14 or to remove the protective hood 15, the hand lever 20 is moved from its position shown in FIG. Rotate away so that the hand lever 20 can occupy the position illustrated in FIG. As a result, the eccentric cam 19 rotates counterclockwise in FIG. 2, and the dimension located between the two fastening members 18 is shortened. Since the spring clasp 23 holds the tightening member 18 with the eccentric cam 19, the tightening member 18 can be separated from the tightening collar 16 and can enter the through-hole 22 of the tightening neck portion 14. As a result, the tightening action among the back wall 211 of the receiving chamber 21, the tightening member 18 and the tightening collar 16 is blocked, and the protective hood 15 can move relative to the tightening neck portion 14.
[Brief description of the drawings]
FIG. 1 is a sectioned bottom view of an angle grinder of the present invention with a protective hood inserted but not locked.
FIG. 2 is a view similar to FIG. 1 with a locked protective hood.
FIG. 3 is a sectional view taken along line III-III in FIG. 1;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Mechanical casing 101 Head part 11 Bearing flange 12 Ball bearing 13 Working spindle 14 Tightening neck part 15 Protective hood 16 Tightening collar 17 Locking device 18 Tightening member 19 Eccentric cams 191 and 192 End face journal 20 Hand lever 21 Receiving chamber 211 Back wall 212 Bottom part 22 Wall through-hole 23 Spring clasp 231 Clasp U-shaped portion 232 Clasp end 233 Spring end 24 Cover 26 Blind hole

Claims (8)

Electric hand-held tool machines such as angle grinders, hand-held circular saws and the like, motor driven, rotary tools such as separating or polishing discs, circular saw plates and the like can be tightened, A machine casing (10) with a bearing flange for rotatably receiving a protruding working spindle and a cylindrical shape formed outside the bearing flange for inserting a protective hood (15) for a rotating tool A tightening neck (14) and a locking device (17) for fixing the protective hood (15) on the tightening neck (14) are provided. The locking device (17) is provided on the tightening neck (14). Locking means (17) that engages the tightening collar (16) of the placed protective hood (15), and the coupling means that is pivotally supported by the bearing flange (11) can be used as an operating position and an inoperative state. In of the type having a hand lever (20) for moving the location,
The locking means (17) has two clamping members (18) movable in the bearing flange (11) and an eccentric cam (19) arranged between them, the eccentric cam (19) being a hand lever. It is coupled to the hand lever (20) so as to be able to rotate during the turning of (20), the clamping member (18) is in contact with the eccentric cam (19) by a frictional connection under the spring force, and the clamping member ( 18) and the configuration of the eccentric cam (19), the eccentric cam (19) moves against the spring force when the hand lever (20) pivots from the released position to the locked position. The fastening member (18) is pressed against the inner wall of the fastening collar (16) of the protective hood (15), and the fastening member (18) and the eccentric cam (19) are provided on the bearing flange (11). Placed in the receiving chamber (21) The tightening neck (14) has a through-wall hole (22) in the region of the receiving chamber (21) for allowing the tightening member (18) to pass through, both tightening members (18) being one Held by a spring clasp (23), with its clasp ends (232, 233) each coupled to one clamping member (18) and to the outer surface of the clamping member opposite the eccentric cam (19); An electric hand-held tool machine characterized in that the clasp U-shaped part (231) of the spring clasp (23) is held on a flat surface (211) in the receiving chamber (21) . Both clamping members (18) are movably arranged in opposite directions, and the mutually aligned directions of movement of the clamping members (18) extend along the chord relative to the circular clamping neck (14). The machine according to claim 1, wherein: An eccentric cam (19) located between the two clamping members (18) is rotatably held in the receiving chamber (21) and is non-rotatably coupled to the hand lever (20) and has a transverse cross section. The machine according to claim 1 , wherein the machine has a substantially square shape with rounded chamfered edges. The eccentric cam (19) is supported by coaxial end face journals (191, 192), and the end face journals (191, 192) are axial lines of the eccentric cam (19) at both end faces of the eccentric cam (19). 4. A machine according to claim 3 , characterized in that it projects coaxially with respect to the bearing and is pivotally received in holes (25, 26) in the bearing flange (11). The non-rotatable connection between the hand lever (20) and the eccentric cam (19) is a square eccentric cam (19) when the hand lever (20) is in contact with the tightening neck (14) (lock position). ) Of the larger cross-sectional axis is aligned with the moving direction of the tightening member (18) and the hand lever (20) is pivoted away from the tightening neck (14) (release position), the eccentric cam ( Device according to claim 3 or 4 , characterized in that the smaller cross-sectional axis of 19) is aligned with the direction of movement of the clamping member (18). Clamping member (18) is characterized in that it is deformable constructed resiliently Machine according Izure of claims 1 to 5. Characterized in that the clamping member (18) is configured as a roller or rollers, machine Izure one of claims 1 to 6. 8. A machine as claimed in claim 7 , characterized in that the roller is made from a solid rubber body or from a steel strip as a hollow cylinder.

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