CN203765467U - Novel dresser for grinding wheel for bearing for asymptotic convergence curve raceway - Google Patents
Novel dresser for grinding wheel for bearing for asymptotic convergence curve raceway Download PDFInfo
- Publication number
- CN203765467U CN203765467U CN201320826129.9U CN201320826129U CN203765467U CN 203765467 U CN203765467 U CN 203765467U CN 201320826129 U CN201320826129 U CN 201320826129U CN 203765467 U CN203765467 U CN 203765467U
- Authority
- CN
- China
- Prior art keywords
- dresser
- shaft
- bearing
- convergence curve
- novel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Grinding-Machine Dressing And Accessory Apparatuses (AREA)
Abstract
The utility model provides a novel dresser for a grinding wheel for a bearing for an asymptotic convergence curve raceway. The novel dresser aims to guarantee that the dressed grinding wheel can meet technical requirements of grinding of the asymptotic convergence curve raceway of the bearing. According to the structure of the novel dresser, a dressing shaft and an eccentric shaft are combined to swing, the eccentric shaft swings around the center of the dressing shaft at a higher speed while a dressing shaft sleeve drives a dressing support to swing around the center Op of the eccentric shaft, and therefore the swinging radius of a diamond pen on the dressing support around the center of the dressing shaft becomes the combination radius of the radius and the eccentricity delta of the eccentric shaft, and a continuous swinging track is an asymptotic convergence curve. The novel dresser has the advantages that assembling of the components is adjusted, so that gapless rotating and sliding are achieved, the convergence curved surface of the grinding wheel is ground, rigidity, stability and continuity of overall work of the dresser for the grinding wheel are guaranteed, technical problems of machining of the asymptotic convergence curve raceway of the ball bearing are solved, and machining is carried out easily.
Description
Technical field
The utility model relates to the equipment for grinding of trimming wheel, relates in particular to a kind of novel asymptotic convergence curve race bearing dresser, is that use diamond pen is that diamond roller is by the equipment for grinding of raceway shape trimming wheel.
Background technology
Existing ball-bearing groove cross sectional shape is circular arc type, and the arc radius of raceway arc radius and steel ball exists certain proportionate relationship, and raceway arc radius is bigger than normal.But with regard to the raceway shape of bearing self, if bearing is under non-homogeneous stressing conditions, be bearing stressed on circumference be heterogeneous, actual contact point (contact angle) the meeting deviation theory design point (contact angle) of rolling element, the bias meeting of stressed large steel ball and raceway contact point is obvious, the contact point of steel ball and raceway is non-circular in the distribution of circumference, in the situation that being subject to tilting moment, detect bearing, will find in bearing, at circumferencial direction, there is axially relatively moving in various degree in outer ring, load is larger, bearing deformation is larger, Internal and external cycle relatively moves more obvious.If steel ball at stressed rear deviation theory contact point simultaneously, can make the contact angle of steel ball and raceway increase fast, reduce the deflection of bearing, the embroidery that contact point of steel ball and raceway distributes can diminish, and therefore adopts the convergence curve raceway of gradual change especially necessary.If lasso raceway adopts convergence curve raceway, the contact point of steel ball and raceway is when being subject to load deviation theory position, in the situation that bearing deformation is less, the contact angle of steel ball and raceway increases can be obvious, meets the requirement of bearing load, and bearing is under identical deflection condition, adopt the contact point increase of convergence curve raceway steel ball more obvious, can make the comprehensive load capacity of bearing obviously improve, anti-rollover performance obviously increases, and operation stability is better.But gradual change convergence curve raceway difficulty of processing is larger, reason mainly contains two:
1. elliptic roller track belongs to the raceway of circular curve radius gradual change, and simulation difficulty is larger, even if adopt the electric control methods such as servo-drive system, is also difficult to realize even without the whole curved surface of node trimming wheel;
2. as dresser itself, the rigidity of operation, stability are the keys that guarantees emery wheel curve form, and traditional simple and mechanical finishing action is to complete the finishing of the emery wheel curved surface of arc radius gradual change.
Therefore, design bearing processing at present still adopts fixing arc raceway, causes the running precision of bearing and product quality to be greatly affected, and especially, in the situation that load is inhomogeneous, the probability of the damage of bearing can obviously increase, and reduces service life.
Summary of the invention
The utility model provides a kind of novel asymptotic convergence curve race bearing dresser, object is to guarantee that the emery wheel being trimmed can meet the specification requirement of bearing gradual change convergence curve ball race grinding, thereby improve running accuracy, the anti-rollover performance of bearing, extend bearing service life.For solving the gradual change convergence curve shape processing problems of raceway, first rigidity, stability and the continuity of dresser be to consider, the accuracy of emery wheel asymptotic convergence curved surface and the validity of grinding bearing gradual change convergence curve raceway that are trimmed also will be considered.
Novel gradual change convergence curve race bearing dresser mentality of designing: the theoretical contact point of steel ball and raceway of take is benchmark, make the raceway arc radius of theoretical contact point both sides be slightly less than the arc radius of contact point, but be not less than the minimum parameter of raceway curve requirement, make the finishing point of trimmer diamond pen present convergent tendency gradually on two side directions of theoretical circular arc contact point, thereby form the convergence curve raceway of a gradual change.The frame mode that trimmer adopts dresser shaft and eccentric shaft combination to swing, at trimmer, swing in dressing process, finishing axle sleeve (driving finishing support) is when eccentric shaft center O p swings, eccentric shaft is swinging around dresser shaft center O x, and eccentric shaft is faster around the swing speed of eccentric shaft center O p than finishing axle sleeve around dresser shaft center O x swing speed, thereby making to be fixed on diamond pen on finishing support becomes around eccentric shaft center O p pendulum radius with around the synthetic radius of dresser shaft center O x pendulum radius δ around the pendulum radius of dresser shaft center O x, form continually varying pendulum radius (continually varying track is gradual change convergence curve), realization is trimmed to gradual change convergence curve shape curved surface to emery wheel working curved surface, thereby in wheel grinding raceway process, guarantee raceway to wear into gradual change convergence curve raceway.
In order to achieve the above object, the utility model is taked following technical scheme: (2) the integral body of trimmer be fixed on grinding machine body correct position (1) by principal saddle, and (20) (3) trimmer agent structure constituted with the eccentric shaft of the dresser shaft (21) swinging and swing by the bolster main shaft swinging.
(3) principal saddle (2) middle part is fixedly connected with main shaft, limit portion assemble can drive oil cylinder I that (7) tooth bar I move up and down (6) with guide rail I (5).
(4) (3) main shaft relatively rotate connection by bearing with outside collar bush; Collar bush be (4) equipped with gear I (8) with joint cover (9), gear I (8) with; (7) tooth bar I meshes; Collar bush (4) end is equipped with and eccentric adjusts pressing plate (10), adjusts (10) fixing dresser shaft (21) of pressing plate, adjusts pressing plate and is (10) connected by chute guide frame with dresser shaft (21); There is an offset A in dresser shaft center O x and alignment of shafts Ow.
(11) (9) joint cover be fixedly connected with finishing seat board, finishing seat board (11) assemble oil cylinder II (14) with guide rail II (17), tooth bar II (12) with tooth bar III (15), side channel is in-built after (15) has spring mechanism (18) for tooth bar III;
(20) eccentric shaft is the inhomogeneous hollow cavity of wall thickness, utilizes bearing assemble with the dresser shaft (21) being loaded in chamber, and eccentric shaft center O p and dresser shaft center O x exist offset δ; (12) (13) the eccentric shaft (20) gear II of one end assembling mesh with tooth bar II; Eccentric shaft (20) the other end and middle part utilize bearing assemble finishing axle sleeve (19) in; (15) (16) finishing axle sleeve (19) outer gear III of installing mesh with tooth bar III; Finishing axle sleeve (19) end is provided with curvature adjustment pressing plate (22); Curvature is adjusted fixedly maintaining support (24) of pressing plate (22), and fixedly maintaining support (24) is equipped with diamond pen (25).
The beneficial effects of the utility model are: dresser is realized gapless rotation and slided by the assembling of adjustment component, guarantee rigidity, stability and the continuity of dresser overall work, dresser has been realized the grinding to emery wheel convergence curved surface, solved the technical barrier to the processing of ball bearing gradual change convergence curve raceway, and processing easy operating; Increase substantially combination property and the service life of rolling bearing.
Accompanying drawing explanation
Below in conjunction with the drawings and specific embodiments, the utility model is described in further detail.
Fig. 1 is trimmer overall structure schematic diagram;
Fig. 2 is dresser shaft and spindle eccentricity stationary water mean place schematic diagram;
Fig. 3 is that dresser shaft is rocked to positive and negative 45 ° of position views;
Fig. 4 is dresser shaft center, eccentric shaft center and alignment of shafts position conllinear schematic diagram;
Fig. 5 is not conllinear schematic diagram of dresser shaft center, eccentric shaft center and alignment of shafts position;
Fig. 6 is the actual crushing asymptotic convergence curve raceway schematic diagram of simulation.；
Fig. 7 is the actual crushing gradual change convergence curve enlarged drawing of simulation.
Illustration: grinding machine body 1, principal saddle 2, main shaft 3, collar bush 4, guide rail I 5, oil cylinder I 6, tooth bar I 7, gear I 8, connecting plate 9, eccentric pressing plate 10, finishing seat board 11, tooth bar II 12, gear II 13, oil cylinder II 14, tooth bar III 15, gear III 16, guide rail II 17, spring mechanism 18, finishing axle sleeve 19, eccentric shaft 20, dresser shaft 21, curvature adjustment pressing plate 22, emery wheel 23, finishing support 24, the diamond pen 25 adjusted.
In figure:
Zw-main spindle's
Zo, Z
1, Z
2-dresser shaft position
Ow-alignment of shafts
Ox, O
1, O
2, O
3, Oa, Ob, Oc, Od-dresser shaft center
A-dresser shaft and spindle eccentricity amount
Op, Op
1, Op
2, Op
3, Op
4-eccentric shaft external diameter center
α-position offset
L
1, L
2-circular curve
R
1, R
2-with O
1, O
2centered by radius
ROp-eccentric shaft external diameter
Rs, Rs
1-always repair radius R s
Po
2, Po
3-finishing support is in orientation
P
0, P
1, P
2, P
3, P
4-diamond pen position
Dw-steel ball
The specific embodiment
As shown in Figure 1,
The integral body of trimmer is fixed on the correct position of grinding machine body 1 by principal saddle 2, trimmer agent structure by main shaft 3 with and the dresser shaft 21 that swings, the eccentric shaft 20 swinging and finishing support 24 constitute.
Principal saddle 2 assembling oil cylinder I 6, guide rail I 5; Oil cylinder I 6 drives tooth bar I 7 to move up and down, and tooth bar I 7 drive shaft covers 4 rotate around alignment of shafts Ow, and 5 pairs of tooth bar I 7 of guide rail I play the guiding role.
Main shaft 3 is fixedly connected with principal saddle 2,3 main supporting roles of main shaft; Main shaft 3 passes through bearing fit with outside collar bush 4; Collar bush 4 is equipped with gear I 8 and joint cover 9, gear I 8 and 7 engagements of tooth bar I; The eccentric pressing plate 10 of adjusting is equipped with in collar bush 4 ends; Because angular contact ball bearing raceway feature is peach-shaped raceway, therefore must adjust dresser shaft center O x and an offset A(of alignment of shafts Ow formation is shown in Fig. 2), according to the size of steel ball size, determine the size of A value, then by bias, adjust pressing plate and be (10) fixedly connected with by chute guide frame with dresser shaft (21); Dresser shaft 21 synchronously rotates with collar bush 4, again along chute rotation.
Joint cover 9 is fixedly connected with finishing seat board 11, finishing seat board 11 assembling oil cylinder II 14 and guide rail II 17, tooth bar II 12 and tooth bar III 15; The rear side channel of tooth bar III 15 is in-built spring mechanism 18, and spring mechanism 18 eliminates by the mode of hinged one end, one end spring pre-tightening because the gap that the bias in gear drive produces.Eccentric shaft 20 is the inhomogeneous hollow cavities of wall thickness, passes through bearing assemble with the dresser shaft 21 being loaded in chamber, and eccentric shaft center O p and dresser shaft center O x exist offset δ; The gear II 13 of eccentric shaft 20 one end assemblings and 12 engagements of tooth bar II; Eccentric shaft 20 middle parts and the other end by bearing assemble finishing axle sleeve 19 in; The gear III 16 of finishing axle sleeve 19 outer installations and 15 engagements of tooth bar III; Finishing axle sleeve 19 ends are provided with curvature and adjust pressing plate 22; Curvature is adjusted the maintaining support 24 that pressing plate 22 is fixedly equipped with diamond pen 25.
As shown in Figure 2, the realization of dresser shaft center O x and alignment of shafts Ow eccentric action, is swung and is realized by oil cylinder I 6; 6 actions of oil cylinder I start to make alignment of shafts Ow and dresser shaft center O x to be horizontal, and offset A is maximum, and dresser shaft 21 is in Z
0position; In oil cylinder I 6 band carry-over bar I 7 or during lower action, driven wheel I 8 is clockwise or counter-clockwise swing around Ow.
As shown in Figure 3, can according to the requirement of raceway, rest on the position (for example negative or positive is 45 °) of proper angle, dresser shaft 21 is rocked to Z
1or Z
2during position, corresponding dresser shaft center O x rotates to O
1, O
2position, trimmer is respectively with O
1, O
2centered by, with R
1, R
2(R
1=R
2) radius swings and to draw circular curve L
1and L
2and position offset α, conform to the status requirement of bearing standard arc raceway; Now dresser shaft center O x rotates to O
1, O
2position is just keeping (or negative) 45 ° of invariant positions, the main eccentric position of rigid bearing raceway, and the main eccentric parameter of raceway can be determined by adjusting the offset A of dresser shaft 21.
As shown in Figure 4, when finishing seat board 11 and the parts that are connected and repair support 24 main bodys with the position that is fixed on joint cover 9 on collar bush 4 and swings to 45 ° of lines, dresser shaft center O x rotates to O
2position, dresser shaft 21 positions by Zo to Z
2, the offset of the external diameter center O p(of the lucky eccentric shaft 20 in this position and dresser shaft center O x is δ) and be positioned at O
2on 45 ° of lines that are connected with Ow, i.e. O
2, Op and Ow position conllinear, finishing support 23 is in Po
2(45 °) position; Total finishing radius R s=δ+ROp.
As shown in Figure 5, when finishing seat board 11 returns to swing with the joint cover 9 being fixed on collar bush 4 since the position of 45 ° of lines with the parts that are connected and finishing support 24 main bodys, dresser shaft center O x is by O
2when position turns to convolution, oil cylinder II 14 band carry-over bar II 12 and 15 actions of tooth bar III, driven wheel II 13 and gear III 16 clockwise rotate simultaneously, and gear II 13 is rotated around Ox, and gear III 16 is rotated around Op.According to emery wheel 23 finishing requirements, the diameter of design gear II 13 is less than the diameter of gear III 16, that is to say, gear II 13 rotating speeds are faster than gear III 16 rotating speeds, and eccentric shaft 20 for example, with speed (2 times) rotation higher than finishing axle sleeve 19, O
3, Op
3, OwSan Ge center forwards non-colinear position to, finishing support 24 is by Po
2forward Po to
3position, always repairs radius R s and becomes Rs
1, Rs
1offset δ, eccentric shaft 20 radius R Op and Rs
1form (with O
3, Op, Po
2for summit) a leg-of-mutton limit, Rs
1be less than Rs.Thus, combination swing along with dresser shaft 21 and eccentric shaft 20, the arc radius that dresser is repaired out emery wheel 23 diminishes the increase along with eccentric shaft 20 pendulum angles, thereby, the circular curve of the emery wheel 23 forming below 45 ° of lines is restrained gradually, the correction of emery wheel 23 circular curves is determined by adjusting the offset δ of eccentric shaft 20, thereby has been guaranteed that circular curve shape guarantees that raceway shape meets the load parameter requirement of bearing.
In like manner, dresser shaft center O x is adjusted to O
1during position, fix, by the action of oil cylinder II 14, can repair out the circular curve of the lower part gradual change of 0 °～-45 ° of emery wheels 23.
As shown in Figure 6, according to the course of action of Fig. 2～Fig. 5, to steel ball Dw raceway, simulation is got a little, and dresser shaft center is placed in to O
2position, the pendulum angle of getting respectively finishing support 24 is 10 ° of (P
1), 20 ° of (P
2), 30 ° of (P
3), 40 ° of (P
4), dresser shaft center swings to Oa, Ob, Oc, Od position by O2 correspondence, and eccentric shaft center pendulum angle corresponds to 20 ° of (Op
1), 40 ° of (Op
2), 60 ° of (Op
3), 80 ° of (Op
4), connect the point that finishing support 24 swings each circular curve of above-mentioned each angle, from P0 point, start to dwindle into gradually gradual change convergence curve to P4 point curve radius (amplifying as Fig. 7).This gradual change convergence curve shape is just consistent with the requirement of ball-bearing groove under non-uniform load condition.
4 angular contact bearing raceways that steel ball (Dw) diameter is 45mm, while being swung with 5 ° of pendulum angles, 10 °, 15 °, 20 °, 25 °, 30 °, 35 °, 40 ° respectively by 45 ° of contact angles, each point line is made circular arc, get from top to bottom 5 points (0 ° of point, 10 ° of points, 20 ° of points, 30 ° of points, 40 ° of points), radius is respectively R23.625mm(ideal position P
0), R23.625mm(P
1position), R23.2195mm (P
2position), R23.1973mm (P
3position), R22.9842mm (P
4position), approaching P
0during position, camber line convergence is not obvious, and pendulum angle is larger, and camber line is restrained more obviously gradually, forms gradual change convergence curve raceway.
Claims (6)
1. a novel asymptotic convergence curve race bearing dresser, it is characterized in that: (2) the integral body of described trimmer be fixed on grinding machine body correct position (1) by principal saddle, (20) (3) trimmer agent structure constituted with the eccentric shaft of the dresser shaft (21) swinging and swing by the bolster main shaft swinging.
2. novel asymptotic convergence curve race bearing dresser according to claim 1, is characterized in that: (3) described principal saddle (2) middle part is fixedly connected with main shaft, limit portion assemble can drive oil cylinder I that (7) tooth bar I move up and down (6) with guide rail I (5).
3. according to novel asymptotic convergence curve race bearing dresser described in claim 1 or 2, it is characterized in that: (4) (3) described main shaft relatively rotate connection by bearing with outside collar bush; Collar bush be (4) equipped with gear I (8) with joint cover (9), gear I (8) with; (7) tooth bar I meshes; Collar bush (4) end is equipped with and eccentric adjusts pressing plate (10), adjusts (10) fixing dresser shaft (21) of pressing plate, adjusts pressing plate and is (10) connected by chute guide frame with dresser shaft (21); There is an offset A in dresser shaft center O x and alignment of shafts Ow.
4. novel asymptotic convergence curve race bearing dresser according to claim 3, it is characterized in that: (11) (9) described joint cover be fixedly connected with finishing seat board, finishing seat board (11) assemble oil cylinder II (14) with guide rail II (17), tooth bar II (12) with tooth bar III (15), side channel is in-built after (15) has spring mechanism (18) for tooth bar III.
5. novel asymptotic convergence curve race bearing dresser according to claim 1, it is characterized in that: (20) described eccentric shaft is the inhomogeneous hollow cavity of wall thickness, utilizing bearing assemble with the dresser shaft (21) being loaded in chamber, there is offset δ in eccentric shaft center O p and dresser shaft center O x; (12) (13) the eccentric shaft (20) gear II of one end assembling mesh with tooth bar II; Eccentric shaft (20) the other end and middle part utilize bearing assemble finishing axle sleeve (19) in.
6. novel asymptotic convergence curve race bearing dresser according to claim 5, is characterized in that: (15) (16) described finishing axle sleeve (19) outer gear III of installing mesh with tooth bar III; Finishing axle sleeve (19) end is provided with curvature adjustment pressing plate (22); Curvature is adjusted pressing plate (22) maintaining support (24) of diamond pen (25) is fixedly housed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320826129.9U CN203765467U (en) | 2013-12-16 | 2013-12-16 | Novel dresser for grinding wheel for bearing for asymptotic convergence curve raceway |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320826129.9U CN203765467U (en) | 2013-12-16 | 2013-12-16 | Novel dresser for grinding wheel for bearing for asymptotic convergence curve raceway |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203765467U true CN203765467U (en) | 2014-08-13 |
Family
ID=51282710
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201320826129.9U Expired - Fee Related CN203765467U (en) | 2013-12-16 | 2013-12-16 | Novel dresser for grinding wheel for bearing for asymptotic convergence curve raceway |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203765467U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103770005A (en) * | 2013-12-16 | 2014-05-07 | 大连联合风电轴承有限公司 | Novel bearing grinding wheel dresser of asymptotic convergence curve roller path |
| CN105234776A (en) * | 2015-09-02 | 2016-01-13 | 无锡市普森精密机床制造有限公司 | Method for machining rolling way of inner ring of bearing and convexity degree of roller |
-
2013
- 2013-12-16 CN CN201320826129.9U patent/CN203765467U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103770005A (en) * | 2013-12-16 | 2014-05-07 | 大连联合风电轴承有限公司 | Novel bearing grinding wheel dresser of asymptotic convergence curve roller path |
| CN103770005B (en) * | 2013-12-16 | 2018-02-27 | 大连联合风电轴承有限公司 | New asymptotic convergence curve race bearing dresser |
| CN105234776A (en) * | 2015-09-02 | 2016-01-13 | 无锡市普森精密机床制造有限公司 | Method for machining rolling way of inner ring of bearing and convexity degree of roller |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104385143B (en) | Grinding wheel dressing method and device for machining bearing inner ring raceway crowning | |
| CN203765467U (en) | Novel dresser for grinding wheel for bearing for asymptotic convergence curve raceway | |
| CN103770005A (en) | Novel bearing grinding wheel dresser of asymptotic convergence curve roller path | |
| CN201998045U (en) | Swing head mechanism for superfinishing machine | |
| CN201361799Y (en) | System for automatically controlling variable angles of grinding wheel main shaft of full-automatic numerical control roll grinding machine | |
| CN208681200U (en) | A kind of plank sanding and polishing machine | |
| CN205033087U (en) | Micro - guiding mechanism of bearing ring groove grinder trimmer | |
| CN208644918U (en) | A kind of spring grinding machine | |
| CN103084980A (en) | Grinding wheel grinding roller | |
| CN105422744B (en) | Double-arc spline freely-supported mechanism and its processing method | |
| CN206662972U (en) | Single-point is axially hard to position radial direction static pressure grinding machine workpiece spindle | |
| CN104511828B (en) | Use and adjustment method for bearing inner ring raceway spiral super-finishing machine | |
| CN208342582U (en) | A kind of swing aligning structure for arc track feeding | |
| CN104108136A (en) | Automatically centripetal double riding wheel mechanism of concrete mixing truck | |
| CN105437063B (en) | Multistation switches precision positioning device | |
| CN203937023U (en) | A kind of concrete mixing and transporting car from trend axle center double supporting wheel mechanism | |
| CN202517376U (en) | Arc dresser for dressing grinding wheel through deep groove ball groove grinder | |
| CN206983180U (en) | A kind of locked mode two plate of injection machine | |
| CN202763677U (en) | Composite grinding oblique line motion control mechanism for rotationally trimming diamond pen | |
| CN203438075U (en) | Bearing grinding wheel trimming mechanism | |
| CN202006403U (en) | Grinding and polishing roller locking mechanism for artificial diamond inclined plane grinding and polishing machine | |
| CN207701607U (en) | A kind of double ditch high-precision emery wheels | |
| CN102975109B (en) | Spherical roller superfinishing method | |
| CN104653597A (en) | Adjustable compound roller bearing | |
| CN201002207Y (en) | Wide belt sander sanding head upper roller rigid centre shaft structure |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20140813 Termination date: 20141216 |
|
| EXPY | Termination of patent right or utility model |