CN1157587A

CN1157587A - Hand-held electric power tool

Info

Publication number: CN1157587A
Application number: CN95195071.1A
Authority: CN
Inventors: A·克莱达
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1994-09-16
Filing date: 1995-08-17
Publication date: 1997-08-20
Anticipated expiration: 2015-08-17
Also published as: DE4432973B4; IT1277563B1; BR9508931A; WO1996008339A1; JPH10505794A; DE4432973A1; ITMI951889A0; ITMI951889A1; CN1074969C

Abstract

The invention concerns a hand-held electric power-tool with a main spindle (13) which turns a rotary tool (18), a chuck (17) designed to clamp the rotary tool (18) rigidly to the spindle (13), and a manually operated lock (25) designed to secure the spindle against rotation when the tool (18) is being changed. In order to ensure an ergonomic, wear-free lock design, the lock (25) has on the one hand a grooved ring (27) with a multiplicity of grooves (28) of arc-shaped cross-section, the ring being fitted round the outside of a flange (19) holding the tool (18), and on the other hand a locking cam (32), with a flattened-circular section, which can be rotated into the grooves (28) and which is mounted on a hand-operated lever which rotates about an axis (30) parallel to that of the spindle (13).

Description

Hand-held electric power tool

Prior art

The present invention relates to a kind of hand-held electric power tool that has a throw, for example the hand-held electric power tool of that class angel grinder of claim 1 preamble definition or portable annular saw and so on.

For example when changing cutting disc or emery wheel or saw blade, fixing when realizing the no instrument of electronic main shaft unscrewed when a manual main shaft stop device prevents in main axis rotation or tightened locking nut being equipped with on the casing at the replacing instrument.When the handle of operation axis stop device, brake cam on the handle just changes in the groove immediately, and combine with the profile of groove and not being contained in clamp flange locking on the main shaft, that firm grip instrument rotationally, to prevent to produce any rotatablely moving by this cam.

In a kind of hand-held electric power tool with the main shaft stop device (German patent DE P43 44 128.9) that had proposed already, the cross section of groove is rectangular, and the clavate brake cam is arranged on the handle that can rotate perpendicular to the axis of main shaft.Because the cross section of groove and this structure of brake cam, the main shaft stop device can not be inserted into arbitrary position of rotation of clamp flange immediately, but after clamp flange carried out certain rotation, brake cam could unhinderedly fall into groove.This rotation of clamp flange is generally along with the loosening of locking nut or tighten and begin to carry out, and brake cam is just gone into groove suddenly when the actuating handle subsequently.This and rotatablely moving suddenly of handle are related.The operator does not notice generally when operating grip overcomes the reset force of back-moving spring whether brake cam goes into the whether stop of groove and clamp flange, rotatablely moving suddenly of handle is unexpected, thereby may decontrol toolroom machine or injury finger when unskilled operation.In addition, main shaft stop device long-term existence considerable wear.

Advantage of the present invention

Hand-held electric power tool of the present invention with claim 1 characteristic feature has such advantage, and promptly brake cam can change on arbitrary position of rotation of clamp flange in the groove of arc-shaped slot also and rotate to gradually in (when the axis of groove and brake cam axis inaccuracy radial fit) screw in clamp flange by brake cam the groove till the profile of the brake cam that scabbles of circle firmly comes in the half slot.Like this, each operation of handle has guaranteed that all effective stop of main shaft stop device and clamp flange are fastening non-rotatable.By on the parallel arbitrary position that the main shaft stop device can be arranged on casing of handle rotation and only account for little room, in other words, only be provided with according to man-machine control viewpoint with main-shaft axis.

Can carry out favourable improvement to the described hand-held electric power tool of claim 1 by the measure described in other claims.

According to preferred constructive form of the present invention, back-moving spring is contained on swivel bolt or the handle, and this back-moving spring tries hard to make swivel bolt to get back on that home position that brake cam jumps out from grooved ring.By such back-moving spring that preferably constitutes with the swivel bolt axis coaxle as the torsion spring that is contained on the swivel bolt guaranteed the main shaft stop device always unclamp and have only the operator in the time of operating grip just effectively.In case handle unclamps, the main shaft stop device rises immediately.

Accompanying drawing

Describe the present invention in detail below in conjunction with an embodiment shown in the drawings.Accompanying drawing is:

Fig. 1 represents the partial cross section figure of the angel grinder cut open along Fig. 2 hatching I-I;

The part bottom view of the angel grinder of looking by Fig. 1 arrow II when Fig. 2 represents to take off emery wheel.

The description of embodiment

In Fig. 1 sectional view and the part angel grinder shown in Fig. 2 bottom view have a casing 10 as an example of hand-held electric power tool, in this casing, be equipped with one and in Fig. 1, can only see the driving motor of driven shaft 11, a gearbox 12 and a main shaft 13.Main shaft 13 can be rotated to support on a ball axis 14 and the needle bearing 15, and these two bearings constitute journal bearings.Wherein, needle bearing 15 is contained on the casing 10, and ball bearing 14 then is contained on made of plastic and the axle journals 16 that casing 10 firmly is connected.Main shaft 13 stretches out axle journal 16, and the throw 18 an of cutting disc or emery wheel and so on is housed in the anchor clamps 17 of adorning on front end 131.Anchor clamps 17 comprise that one is inserted into and does not rotate on main shaft 13 front ends 131 and with main shaft and radial and axial clamp flange 19 and the locking nut 20 be connected that do not move, and locking nut can be tightened at the thread segment on the front end 131 21.Center internal point 22 of throw 18 usefulness firmly is contained on the installation axle journal 23 that constitutes on clamp flange 19 front ends, and compresses with the annular end face 191 of locking nut 20 facing to clamp flange 19.In case of necessity, also can between locking nut 20 and discoidal throw 18, fill up a fastening pad 24.

When unclamping and tighten locking nut 20, main shaft 13 must be fixing, to prevent rotation.For this reason, be provided with a main shaft stop device 25, in operation this when device, main shaft 13 just is fixed on the axle journal 16 and no longer rotation.For this reason, main shaft stop device 25 have on the one hand one in clamp flange 19 outsides by a plurality of grooved rings of forming apart from the groove 28 of the band circular arc cross section that staggers mutually by same angular 27, have again on the other hand one 27 coacting with grooved ring, be with and scabble the brake cam 32 of circular cross-section.The profile of the cross section of groove 28 and brake cam 32 coincide up and down, so that brake cam 32 is fitted with groove 28.Constitute brake cam 32 on the free end of swivel bolt 31, this bolt is rotatable to be bearing on the axle journal 16, and its rotation 30 is parallel with the axis of main shaft.Handle 29 is not connected rotatably with swivel bolt 31, and the preferably whole moulding of handle 29, swivel bolt 31 and brake cam 32.Handle 29 is arranged on the end that swivel bolt 31 deviates from brake cam 32, and swivel bolt section 311 exceeds handle 29.Adorn a back-moving spring 33 that constitutes as torsionspring on swivel bolt section 311, an end of this spring is fixed on the axle journal 16, and the other end then is fixed on the swivel bolt 31.Back-moving spring 33 is designed to try hard to make swivel bolt 31 to rotate to the home position that brake cam 32 spins out fully from groove 28, and directly radially is parked in the front (illustrated in figures 1 and 2) of the grooved ring 27 of clamp flange 19.This home position of swivel bolt 31 or brake cam 32 is predefined by a block 34 that constitutes on axle journal 16, and handle 29 leans against (Fig. 2) on this block.Sub-handle 29 stretches out axle journal a little by a hole 35 on the axle journal 16, and has a block operations plate 291 (Fig. 1) at pommel.

When changing throw 18, at first unscrew locking nut 20 with spanner.For fixed main shaft 13, the operator is put into a finger on the operation panel 291 of handle 29, and handle is rotated along direction shown in Fig. 2 arrow 26.Like this, swivel bolt overcomes the power of back-moving spring 33 and rotates along Fig. 2 clockwise direction, so semicircular brake cam 32 just changes in the semi-circular groove 28 of grooved ring 27.By the profile combination between groove 28 and the brake cam 32, being in one's hands, clamp flange 19 and main shaft 13 just cannot not stop rotatablely when stopping handle 29.At this moment just available spanner unclamps locking nut 20 smoothly.After changing throw 18, main shaft 13 needs identical locking when tightening locking nut 20.

If tightening locking nut 20 back operator's unclamp operation bars 29, then back-moving spring 33 makes swivel bolt 31 along Fig. 2 counter rotation, till action bars 29 is blocked by the block on the axle journal 16 34.Carry out this when rotatablely moving at swivel bolt 31, brake cam 32 produces from groove 28 reliably fully, so clamp flange 19 just rotatablely moves freely.

Claims

1. hand-held electric power tool has a casing (10), one piece stretches out casing, be used for the electronic main shaft (13) of a throw of transmission (18), one is not fixed on anchor clamps (17) on the main shaft (13) rotatably with throw (18), these anchor clamps (17) do not rotate and axially do not move fixing clamp flange (19) and be used for supporting and/or clamping throw (18) and one and be used for throw (18) firmly is pressed onto on the clamp flange (19) at the locking nut (20) that can tighten on main shaft (13) front end (131) thread segment (21) having one on main shaft (13) front end (131), and have a manual main shaft stop device (25) and be used for fixed main shaft (13) when changing throw (18), to prevent rotation, this device (25) one of clamp flange (19) outer setting by a plurality of by the handle (29) that equates that grooved ring (27) that the anglec of rotation is formed apart from the grooves (28) that stagger mutually and can rotate around the rotating shaft (30) that is fixed on the casing (10), handle is provided with a brake cam (32) that can change in the groove (28), it is characterized in that, groove (28) is the circular arc cross section, the rotation (30) of handle (29) is parallel with the axis of main shaft (13), and one with the coaxial swivel bolt (31) of the rotation (30) of handle (29) on brake cam (32) cooperate with the circular cross section that scabbles of groove cross section.

2. press the toolroom machine of claim 1, it is characterized in that, swivel bolt (31) can be rotated to support in the axle journal (16) of a main shaft (13) that firmly is connected with casing (10), and the handle (29) that is not connected rotatably with swivel bolt (31) meets at right angles with swivel bolt and protruding by the hole (35) on the axle journal (16), and at pommel one block operations plate (291) arranged.

3. by the toolroom machine of claim 1 or 2, it is characterized in that brake cam (32) constitutes whole with swivel bolt (31) and is arranged on the free end of the swivel bolt (31) that stretches out from axle journal (16).

4. by the toolroom machine of claim 2 or 3, it is characterized in that handle (29) is fixed on swivel bolt (31) near brake cam one end, best and its formation integral body.

5. by each toolroom machine of claim 1 to 4, it is characterized in that, back-moving spring (33) is connected on swivel bolt (31) or the handle (29), and this back-moving spring tries hard to make swivel bolt (31) to reset to the home position that brake cam (32) comes out from grooved ring (27) transfer fully.

6. by the toolroom machine of claim 5, it is characterized in that the home position of swivel bolt (31) is gone up the block (34) that constitutes by axle journal (16) and set, handle (29) is being accommodated on this block under the effect of back-moving spring (33).

7. by the toolroom machine of claim 5 or 6, it is characterized in that back-moving spring (33) is made of a torsion spring that is contained on the swivel bolt (31), an end of this spring is fixed on the swivel bolt (31), and the other end then is fixed on the axle journal (16).

8. by the toolroom machine of claim 7, it is characterized in that swivel bolt (31) has one section bolt section (311) that exceeds handle (29), and torsion spring set is contained on the bolt section (311).