CN2322722Y

CN2322722Y - Live centre

Info

Publication number: CN2322722Y
Application number: CN 98206569
Authority: CN
Inventors: 李虎孟
Original assignee: Individual
Current assignee: RUYANG COUNTY ELECTRIC POWER BUREAU
Priority date: 1998-07-03
Filing date: 1998-07-03
Publication date: 1999-06-09
Anticipated expiration: 2008-07-03

Abstract

The utility model relates to a movable centre, which comprises a casing, a centre body, rolling bearings, a thrust bearing, a bearing row, a distance bushing of the bearing row, a liner, a sealing cover and a bottom cap. Two sets of rolling bearings used for supporting are arranged between the neck of the centre and the casing, the liner arranged between the neck of the centre and the rolling bearings has a 1: 12 taper, and 7-10 sets of bearing rows used for supporting are arranged between the body of the centre and the casing. The interior edge of the sealing cover is tightly fitted with the external edge of the head of the centre by a sealing fill-ring, the inside can not be easily contaminated, and the service life of the utility model is long. The utility model has the advantages of simple structure, reasonable structure, high machining precision, strong load capacity, low cost, and convenient operation.

Description

Novel live center

The utility model relates to a kind of live center, belongs to a kind of auxiliary mould tool that is used for grinding, particularly to large-scale and heavy workpiece, and the live center that adopts during workpiece grinding such as roll for example.The grinding of heavy type and large-scale workpiece, generally all adopt top mill and two kinds of forms of holder mill at home and abroad, but its pluses and minuses are arranged respectively, for top mill mode, top employing back dead centre, and be the location benchmark with the center hole, workpiece jack-up revolution grinding, back dead centre is bearing tens of tons axial force and radial load, for this reason, very high to top and required precision center hole, the rotation of workpiece a few hours will produce violent friction between top and center hole, the frictional heat that is produced will make back dead centre and center hole generation deformation, cause workpiece to scrap, simultaneously, also can be because of the quality problems of center hole, usually need to repair and grind center hole, have a strong impact on the workpiece quality processed but top mill formal operations are simple, non-cutting time is few, the production efficiency height.Holder mill form is then opposite, and its advantage is the grinding accuracy height, steady quality, but for the workpiece of tens of tons of weights, carriage and tray long-time (a few hours) bear so big load, produce temperature rise, cause workpiece dimension control difficult, and carriage is adjusted complicated.

Because live center has the advantage of back dead centre, can overcome the deficiency of back dead centre again, significant progress is arranged in recent years, China Patent No. 94205478 and 95217777 discloses a kind of live center, they have overcome the problem of above-mentioned existence to a certain extent, but also has certain defective, because the existence of rolling bearing, top neck contacts with a rolling element or is between two rolling elements when contacting with two rolling elements, top neck location has small shake, it is fine uneven that the surface of the work of processing is had, and causes the decline of machining accuracy; The existence of thrust bearing, heating that the friction between thrust bearing and housing causes and wearing and tearing descend machining accuracy; In addition, always there is certain clearance between housing and top body, makes the little bits of processing constantly enter and increase wearing and tearing, reduced the life-span of live center.

The purpose of this utility model is to overcome the deficiencies in the prior art and provides novel live center for work posts such as grindings, it is the advantage of the existing live center of tool maintenance both, and structurally reduce and shake, reduce friction, to improve the precision and the reliability of processing work, bearing capacity is strong, and structure arrangement is reasonable, and cost is low.

The utility model is to realize like this, the utility model includes top body, housing, rolling bearing body and retainer thereof, thrust bearing, bearing row and retainer thereof, tapered sleeve, envelope lid and bottom cap, top body is made up of centre head, top neck and top body, top body combines with the housing rolling by rolling bearing body, thrust bearing and bearing row, the front and back ends of housing is closed by capping or end cap, it is characterized in that being supported by two cover rolling bearing bodies between top neck and housing.The tapered sleeve that supports top neck and roller bearing shop has 1: 12 tapering, and the inner edge of capping has cannelure, has sealing to fill out the outer rim close fit of circle and centre head in the cannelure.

Two cover back-up roller dynamic bearing bodies of housing and top collar are and intersect little the trembling of the rolling bearing body arranged generation when having reduced top running, have promptly improved the machining accuracy of surface of the work more.

Bearing row is the 7-10 cover, is at least 7 covers; The inner edge that bearing is arranged the retainer between each rolling element has one to adjust packing ring, and the width of adjusting packing ring is slightly larger than the width of retainer.

With screw threaded, cap and housing screw togather with screw thread the front end of housing at the bottom of the rear end by capping and housing.

Be provided with the retainer packing ring between the retainer of housing and rolling bearing body.

The retainer of rolling bearing body and the best of the fit-up gap between capping are 0.01mm.

Centre head, top neck and top as integrative-structure are tapering transition between top neck and top body.

The utility model compared with the prior art, its advantage is:

1. the utility model housing and top collar are by two cover back-up roller dynamic bearing bodies and intersect arrangements, and little the trembling of generation when having reduced top the running improved the machining accuracy of surface of the work, the utility model is simple and reasonable for structure, the machining accuracy height, and bearing capacity is strong, cheap, easy to use;

2. the outer rim of capping inner edge of the present utility model and centre head has sealing to fill out the circle close fit, and inside is difficult for contaminated, long service life.

Description of drawings

Fig. 1 is a cutaway view of the present utility model;

Fig. 2 is that the rolling element of two rolling bearing bodies 4 is arranged the expansion schematic diagram.

Accompanying drawing is described in conjunction with the embodiments:

As shown in Figure 1, the utility model includes top body, housing 6, rolling bearing body 4 and retainer 2 thereof, thrust bearing 7, bearing row 8 and retainer 9 thereof, tapered sleeve 15, capping 3 and end cap 12, top body is by centre head 1, top neck 16 and top body 17 are formed, top body is by rolling bearing body 4, thrust bearing 7 and bearing row 8 combines with housing 6 rollings, before the housing 6, the rear end is covered by capping 3 or end cap 12, it is characterized in that 6 of top neck 16 and housings overlap rolling bearing bodies 4 by two and support, cover rolling bearing body support by prior art changes two cover rolling bearing bodies supports into, thereby the length of one side rolling bearing body reduces its diameter and also reduces, spacing between rolling bearing body ball reduces, reduce the trickle shake of surface of the work, thereby improved machining accuracy; Two cover back-up roller dynamic bearing bodies 4 of housing 6 and 16 on top neck are and intersect the arrangement (see figure 2), the rolling bearing body of cross arrangement more reduces the trickle shake of surface of the work, it is identical to reduce ripple to be equivalent to make full-wave rectification into from halfwave rectifier in the rectification circuit, has promptly improved the machining accuracy of workpiece more.Simultaneously, because rolling bearing body diameter reduces, make whole top weight saving, and its bearing capacity is not fallen.The tapered sleeve 15 that supports 4 on top neck 16 and rolling bearing has 1: 12 tapering, and the inner edge of capping 3 has cannelure 18, has sealing to fill out the outer rim close fit of circle 14 and centre head 1 in the cannelure 18.

Bearing row 8 is the 7-10 cover, is at least 7 covers, and bearing is arranged the increase of 8 quantity, can use less rolling element, and its advantage is identical with rolling bearing body 4; The inner edge of the retainer 9 between bearing row 8 each rolling element has one to adjust packing ring 11, the width of adjusting packing ring 11 is slightly larger than the width of retainer 9,8 be subjected to huge pressure when adding man-hour bearing row, owing to adjust the existence of packing ring 11, retainer 9 do not stressed and indeformable.

The front end of housing 6 is screwed togather with bolt 13 by capping 3 and housing 6, and cap 12 and housing 6 screw togather with screw thread at the bottom of the rear end.

2 of the retainers of housing 6 and rolling bearing body 4 are provided with retainer packing ring 5, can prevent preferably that the particulate of processing bits from entering top body inside.

Fit-up gap the best that the retainer 2 of rolling bearing body 4 and capping are 3 is 0.01mm.

Centre head 1, top neck 16 are structure as a whole with

top body

17, and 17 of top neck 16 and top bodies are tapering transition.

Claims

1. novel live center, include top body, housing (6), rolling bearing body (4) and retainer (2) thereof, thrust bearing (7), bearing row (8) and retainer (9) thereof, tapered sleeve (15), capping (3) and end cap (12), top body is by centre head (1), top neck (16) and top body (17) are formed, top body is by rolling bearing body (4), thrust bearing (7) and bearing row (8) combine with housing (6) rolling, before the housing (6), the rear end is covered by capping (3) or end cap (12), it is characterized in that supporting by two cover rolling bearing bodies (4) between top neck (16) and housing (6), tapered sleeve (15) between top neck (16) and rolling bearing (4) has 1: 12 tapering, the inner edge of capping (3) has cannelure (18), has sealing to fill out the outer rim close fit of circle (14) and centre head (1) in the cannelure (18).

2. novel live center according to claim 1, it is characterized in that two cover back-up roller dynamic bearings (4) between housing (6) and top neck (16) are intersects arrangement.

3. novel live center according to claim 1 is characterized in that bearing row (8) and retainer (9) thereof are the 7-10 cover.

4. novel live center according to claim 1 is characterized in that the inner edge of the retainer (9) between each rolling element of bearing row (8) has one to adjust packing ring (11).

5. novel live center according to claim 4, the width that it is characterized in that adjusting packing ring (11) is slightly larger than the width of retainer (9).

6. novel live center according to claim 1 is characterized in that the front end of housing (6) is screwed togather with bolt (13) by capping (3) and housing (6), and cap at the bottom of the rear end (12) screws togather with screw thread with housing (6).

7. novel live center according to claim 1 is characterized in that being provided with retainer packing ring (5) between the retainer (2) of housing (6) and rolling bearing body (4).

8. novel live center according to claim 1 is characterized in that the retainer (2) of rolling bearing body (4) and the best of the fit-up gap between capping (3) are 0.01mm.

9. novel live center according to claim 1 is characterized in that centre head (1), top neck (16) are structure as a whole with top body (17).

10. novel live center according to claim 1 is characterized in that being between top neck (16) and top body (17) tapering transition.