US3678916A

US3678916A - Apparatus for dressing side surfaces of grinding wheels

Info

Publication number: US3678916A
Application number: US119496A
Authority: US
Inventors: Tsuneji Fujii
Original assignee: Toyoda Koki KK
Current assignee: Toyoda Koki KK
Priority date: 1970-03-30
Filing date: 1971-03-01
Publication date: 1972-07-25
Anticipated expiration: 1989-07-25
Also published as: JPS496783Y1; DE2115420A1; FR2087900A5

Abstract

In apparatus for dressing side surfaces of a grinding wheel, there are provided a base swung in a plane parallel to the side surfaces of the grinding wheel, a pair of rotary dressing tools journalled by a pair of supporting members mounted on the base on both sides of the grinding wheel, and a drive mechanism for rotating the dressing tools. In addition, there are further provided adjusting means for moving the supporting members and the rotary dressing tools toward and away from the side surfaces of the grinding wheel without the necessity of operating the drive mechanism.

Description

United States Patent Fu'ii 1451 July 25, 1972 54] APPARATUS FOR DRESSING SIDE 2,148,120 2/1939 Hall ..125/11 ST 2,077,363 4/1937 l-lulbert.. ....125 11 ST SURFACES 0F GRINDING WHEELS 3,552,375 1 1971 Carr ..125 11 c1) [72] Inventor: Tsuneji Fujii, Kariya, Japan Primary Examiner-Harold D. Whitehead [73] Ass1gnee. Toyoda Kokl Kabushlkl Kaisha, Kariya- An0mey wendemth Lind & Ponack shi, Japan [22] Filed: March 1, 1971 [57] ABSTRACT [21] Appl. No.: 119,496 In apparatus for dressing side surfaces of a grinding wheel, there are provided a base swung in a plane parallel to the side surfaces of the grinding wheel, a pair of rotary dressing tools [30] Forelgn Apphcauon Prmr'ty Data journalled by a pair of supporting members mounted on the March 30, 1970 Japan ..45/30465 base on both Sides of the grinding Wheel, and a drive mechanism for rotating the dressing tools. In addition, there [52] U.S. Cl ..l25/ ll CD, l25/l I ST are further Provided adjusting means for moving FP 51 2' 53/14 ing members and the rotary dressing tools toward and away 53 1 Field of Search 125 1 1 from the Side Surfaces of the grinding Wheel Without the necessity of operating the drive mechanism. [56] References Cited 8 Claims, 4 Drawing Figures UN [TED STATES PATENTS 3,581,730 6/1971 Boyd ..125/ll CD 11 F' r E 1112 1 10 I- 111 v I? I? I? Ill A14 in T Patented July 25, 1972 3,678,916

4 Sheets-Sheet 1 If 'ENTOR ,7 MMMQZMMZ ATTORNEKS Patented July 25, 1972 3,678,916

4 Sheets-Sheet 2 INVENTOR Wfi/ AUMIMAC Z ATTORNEYS Patented July 25, 1972 4 Sheets-Sheet 3 I? VENT 9R MM ATTORNEY Patented July 25, 1972 3,678,916

43heets-Sheet 4 Q a 9 an 5 0Q 2 a Q 5 E an; gm N o o O O o o o o 5 2 Q Q 0 0P0 M n 5 .5

APPARATUS FOR DRESSING SIDE SURFACES OF GRINDING WHEELS BACKGROUND OF THE INVENTION This invention relates to an improved apparatus for dressing the side surfaces of a grinding wheel.

In prior apparatus for dressing opposite surfaces of a grinding wheel by using a single rotary dressing tool, the grinding wheel is forced to be displaced by the side pressure applied thereto by the rotary dressing tool, which results in a lower parallelism between side surfaces of the grinding wheel. In addition, twice dressing operations are required to dress a single grinding wheel. Thus, the efficiency of the operation is lower.

Furthermore, in a prior dressing apparatus utilizing a rotary dressing tool, the rotary dressing tool is moved in its straight path of travel in a direction perpendicular to the axis of the grinding wheel, whereby a rapid wear takes place on the forward end periphery of the rotary dressing tool.

Moreover, in such prior dressing apparatus, as the shaft carrying the rotary dressing tool is connected to a rotating driving mechanism, it is difiicult to finely adjust the cutting depth of the dressing tool without adjustment of such driving mechanism.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a new and improved dressing apparatus for simultaneously dressing opposite surfaces of a grinding wheel whereby the grinding wheel is not displaced by the side pressure applied thereto by the rotary dressing tool.

Another object of the present invention is to provide an improved apparatus for simultaneously dressing opposite side surfaces of a grinding wheel by utilizing a pair of swinging rotary dressing tools.

A further object of the present invention is to provide a novel apparatus for simultaneously dressing opposite surfaces of a grinding wheel which can provide fine adjustment of the cutting depth of the rotary dressing tools without the recessity of operating a rotating driving mechanism.

According to the present invention, these and further objects can be accomplished by providing a dressing apparatus comprising a base, means to swing the base in a plane parallel to the side surfaces of the grinding wheel, a pair of supporting members mounted on the base on the opposite sides of the grinding wheel, a first shaft rotatably mounted in each of the supporting members, a rotary dressing tool mounted on each first shaft, a second shaft drivingly connected to a driving means, and a drive connection between the second shaft and each first shaft.

In addition, there are further provided means to move each supporting member and hence the rotary dressing tool associated therewith toward and away from each side surface of the grinding wheel and means to prevent the drive connection from being released upon movement of each supporting member toward and away from each side surface of the grinding wheel.

BRIEF DESCRIPTION OF THE DRAWINGS The invention can be move fully understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 shows a cross-sectional view of a dressing apparatus embodying the invention;

FIG. 2 shows an enlarged section taken along a line IIII in FIG. 1;

FIG. 3 shows a section taken along a line IIIIII in FIG. 2 and FIG. 4 shows an enlarged sectional view taken along a line IVIV in FIG. 1.

A preferred embodiment shown in the accompanying drawings comprises a base 1 supported on the rear side of a guard plate 7 to be rotatable in a plane parallel to the side surfaces of a plurality of grinding wheels 3. Thus, the sleeve in of base 1 is rotatably mounted on a shaft 2 through bearings. One end of shaft 2 being journalled in a casing 8 secured on a grinding wheel carriage, not shown, in a manner not to be movable in the axial direction. A plurality of pairs of supporting members 4 are adjustably mounted on the base 1 by bolts 36, each pair of supporting members 4 being disposed on the opposite sides of one of the grinding wheels 3 mounted on a common shaft, not shown.

An intermediate shaft 5 is supported at its opposite ends by bearings 40 and 41 mounted in casings 9 and 42, respectively, secured to the base 1 (FIGS. 1, 3). The shaft 5 extends through the base portions 43 of respective supporting members 4 and is journalled by

bearings

44 and 45 mounted therein, as shown in FIG. 3. A bevel gear 11 keyed to one end of shaft 5 is driven by a bevel gear 6 keyed to the shaft 19 of a driving motor 20 secured to casing 42. As best shown in FIG. 3, in each supporting member 4 is rotatablyjournalled a rotary shaft 12 at right angles with respect to the intermediate shaft 5. A rotary dressing tool 10 is secured to one end of each shaft 12 and a bevel gear 15 is keyed to the inner end thereof to mesh a corresponding bevel gear 16 keyed to intermediate shaft 5. Thus, when motor 20 is started, shafts 12 are rotated through

gears

6 and 11, intermediate shaft 5 and

gears

16 and 15.

A collar 46, loosely mounted on the intermediate shaft 5, is disposed between bearing 45 and bevel gear 16 within the base portion 43 of each supporting member 4 to locate the bevel gear 16 in meshing engagement with the bevel gear 15 of rotary shaft 12. Accordingly, when each supporting member 4 is moved for adjustment of cutting depth of rotary dressing tool 10, as described later in detail, the associated

bearings

44 and 45, bevel gear 16 and collar 46 are moved therewith as a unit, whereby the bevel gear 15 of the rotary shaft 12 is held in meshing engagement with its associated bevel gear 16.

A gear box 13 is securely fixed to the righthand side of guard plate 7, as viewed in FIG. 1. Housed in gear box 13 is a worm wheel 21 which is secured to one end of sleeve 1a of the base 1 and freely mounted on the driving shaft 2 extending through the gear box 13. As shown in FIG. 4, a worm shaft 17.

with an integral worm 22 meshing worm wheel 21 is mounted in the gear box 13 to be slidable in a direction perpendicular to driving shaft 2. One end of worm shaft 17 is connected to a piston 18, slidably received in a cylinder 14, in a manner to be rotatable but not movable in the axial direction with respect thereto.

Fluid ports

14a and 14b are communicated with a source of fluid under pressure via a change over valve, not shown. Furthermore, a cylinder 23 is formed on the righthand side of gear box 13, as viewed in FIG. 4, to slidably receive a piston 24 with integral piston rods 25 and 26 extending outwardly and inwardly, respectively of the gear box. Piston rod 25 carries a pair of spaced apart

dogs

27a and 27b cooperating with limit switches 31a and 3112 whereas the inner end of piston rod 26 cooperates with a stop 28 secured to the end surface of worm wheel 21. Stop 28 is arranged to engage piston rod 26 in its left end position, as shown in FIG. 4 during a period in which the dressing operation of the grinding wheels 3 is not performed to prevent rotation of worm wheel 21 so as to maintain supporting members 4 and hence base 1 at the solid line position shown in FIG. 2. The lefthand chamber 23a and the righthand chamber 23b of cylinder 23 are communicated with a source of fluid under pressure via a change over valve, not shown. Further, a pair of circumferentially spaced apart

dogs

29a and 29b are secured to the end surface of worm wheel 21 to actuate

limit switches

30a and 30b, respectively. Consequently, when the pressurized fluid is admitted into the lefthand chamber 23a of cylinder 23, piston 23 is moved to the right as viewed in FIG. 2 to disengage piston rod 26 from stop 28, thus permitting worm wheel 21 to rotate freely. Then, the

pressurized fluid is admitted into the cylinder 14 through port 14a to slide worm shaft 17 toward right as viewed in FIG. 4 to rotate worm wheel 21 through worm 22 whereby the base 1 is tilted about driving shaft 2. Thus, the entire widths of rotary dressing tools 10 are simultaneously brought into engagement with the grinding wheel, whereby the grinding wheel is not displaced by the side pressures applied thereto by the rotary dressing tools 10.

As shown in FIGS. 1, 2 and 3, plates 34 are securely fixed on base 1 on the opposite sides of each pair of supporting members 4. As best shown in FIG. 3, an adjusting bolt 35 extends through each plate 34 in a manner not to be movable in the axial direction, the inner threaded end of the bolt being threaded into the supporting member 4. An elongated guide 32 is secured on the upper surface of base 1 in parallel with the axes of grinding wheels. The guide 32 is received in a groove 33 formed in the upper surface of base 1 beneath supporting members 4 and plates 34 as shown in FIG. 2. Thus, the adjustment of the feed or cutting depth of the dressing tools 10 into the side surfaces of the grinding wheel 3 is made by loosening bolts 36, and the rotating adjusting bolts 35 for moving supporting members 4 along guide 32.

The operation of the moved dressing apparatus is as follows. To dress opposite side surfaces of grinding wheels 3, at first driving motor 20 is started to drive intermediate shaft 5 through

bevel gears

6 and 11. The rotation of intermediate shaft 5 is transmitted to rotary dressing tools 10 through bevel gears 16 and and shafts 12. It should be understood that concurrently with the operation of motor 20 the shaft for driving grinding wheels is also rotated by a driving motor not shown. Then, the pressurized fluid is admitted into lefthand chamber 23a of cylinder 23 of gear box 13 to drive piston 24 and piston rods 25 and 26 to the right. As a consequence, piston rod 26 is disengaged from stop 28 to release worm wheel 21. Movement of piston rod 25 causes dog 27a to actuate limit switch 31a to indicate the forward movement of piston 24. Responsive to the operation of limit switch 31a, the pressurized fluid is supplied to cylinder 14 through its port 14a to advance piston 18 together with worm shaft 17 whereby worm wheel 21 is rotated. As above described, since worm wheel 21 is secured to sleeve 1a of base 1, base 1 is tilted downwardly about driving shaft 2. Consequently, supporting members 4 are also rotated about shaft 2 from the solid line position to the dot and dash line position shown in FIG. 2 to simultaneously dress both side surfaces of each grinding wheel by the dressing tools 10 carried by the supporting members. When dog 29a actuates limit switch 30a mounted on gear box 13, the change over valve, not shown, is operated to admit the pressurized fluid into cylinder 14 through port 14b thus moving worm shaft 17 in the opposite direction. Accordingly, worm wheel 21 is roted in the opposite direction to restore base 1, supporting members 4 and dressing tools to the original position shown by solid lines. At this position, dog 29b operates the other limit switch 30b to switch the change over valve to admit the pressurized fluid into cylinder 14 through port 1412. In tlu's manner, rotary dressing tools 10 are continuously oscillated about shaft '2 to perform the dressing operation on both side surfaces of each grinding wheel 3. To adjust the cutting depth of respective dressing tools 10, while supporting members 4 are maintained at the solid line position,

bolts 36 are loosened and then adjusting'bolts are rotated to move supporting members 4 along guide 32 together with shafts 12 and gears 15, 16,

bearings

44, 45 and collars 46 contained in the cylinders 4. Such adjustment is made several times until the width of each grinding wheel has been dressed to a predetermined width. Upon completion of the dressing operation supporting members 4 and dressing tools 10 are brought back to the solid lineposition shown in FIG. 2, and the supply of the pressurized fluid to cylinder 14is interrupted while at the same time driving motor 20 is deenergized. The pressurized fluid is admitted into the righthand chamber 23b of cylinder 23 to move piston 23 to the left to engage piston rod 26 against stop 28 whereby the rotation of supporting members 4 is prevented. Since both side surfaces of each grinding wheel 3 are dressed simultaneously, side surfaces thereof are never be displaced by the side pressures applied by rotary dressing tools thus assuring high accuracy of dressing. Furthermore, since the entire widths of rotary dressing tools are simultaneously brought into engagement with each grinding wheel 3, weardoes not take place on the forward end periphery of each dressing tool 10. From the foregoing description it will be clear that the invention provides a novel apparatus for simultaneously dressing both side surfaces of a grinding wheel wherein supporting members for the both side surfaces are secured to a base supported in a guard plate to oscillate in a plane parallel to the side surfaces of the grinding wheel, rotary dressing tools are rotatably joumalled in the supporting members and the supporting members are moved along a guide by turning adjusting bolts threaded in the cylinders so as to adjust the cutting depth of the dressing tools. With this construction, it is possible not only to simultaneously dress both side surfaces of the grinding wheel at a high efficiency but to prevent the displacement of the side surfaces caused by the side pressure applied thereto by the dressing tools thus dressing these surfaces with extremely high accuracies. Since the adjustment of the cutting depth of the dressing tools is made without operating the driving mechanism of the rotary dressing tools such adjustment can be made readily.

While the invention has been shown and described in terms of a preferred embodiment many changes and modifications will be obvious to those skilled in the art without departing from the true spirit and scope of the invention as defined in the appended claims.

What is claimed is 1. Apparatus for dressing side surfaces of a grinding wheel comprising a base, means to swing said base in a plane parallel to said side surfaces, a pair of supporting members mounted on said base on the opposite sides of said grinding wheel, a first shaft rotatably mounted in each of said supporting members, a rotary dressing tool mounted on each first shaft, a second shaft drivingly connected to driving means, and a drive connection between said second shaft and each first shaft.

2. The dressing apparatus according to claim 1, wherein there are further provided means for moving each supporting member and hence the rotary dressing too] associated therewith toward and away from each side surface of said grinding wheel, and means for preventing said drive connection from being released upon movement of each supporting member toward and away from each side surface of said grinding wheel.

3. The dressing apparatus according to claim 2, wherein said second shaft is disposed in parallel with the axis of said grinding wheel and said drive connection comprises a bevel gear secured to one end of each first shaft, and a bevel gear keyed to said second shaft and meshing with said first mentioned bevel gear.

4. The dressing apparatus according to claim 2 wherein said base comprises a sleeve rotatably mounted on a third shaft, and said base is oscillated about said third shaft together with said supporting members and said rotary dressing tools by means of a double acting piston cylinder assembly.

5. The dressing apparatus according to claim 2 wherein said means for moving each supporting member comprises an adjusting bolt threaded into each supporting member and sup ported by said base.

6. The dressing apparatus according to claim 2 wherein said movement of said supporting member towards and away from the side surfaces of said grinding wheel is guided by guide means located on said base beneath said supporting members.

7. The dressing apparatus according to claim 4 wherein said sleeve of said base is operated by said double acting pistoncylinder assembly through a worm wheel rotated by said piston-cylinder assembly and means is provided to lock and unlock the rotation of said worm wheel.

8. The dressing apparatus according to claim 7 wherein means responsive to a predetermined angle of rotation of said worm wheel are provided for periodically reversing the operation of said double acting piston-cylinder assembly.

Claims

1. Apparatus for dressing side surfaces of a grinding wheel comprising a base, means to swing said base in a plane parallel to said side surfaces, a pair of supporting members mounted on said base on the opposite sides of said grinding wheel, a first shaft rotatably mounted in each of said supporting members, a rotary dressing tool mounted on each first shaft, a second shaft drivingly connected to driving means, and a drive connection between said second shaft and each first shaft.

2. The dressing apparatus according to claim 1, wherein there are further provided means for moving each supporting member and hence the rotary dressing tool associated therewith toward and away from each side surface of said grinding wheel, and means for preventing said drive connection from being released upon movemEnt of each supporting member toward and away from each side surface of said grinding wheel.

5. The dressing apparatus according to claim 2 wherein said means for moving each supporting member comprises an adjusting bolt threaded into each supporting member and supported by said base.

7. The dressing apparatus according to claim 4 wherein said sleeve of said base is operated by said double acting piston-cylinder assembly through a worm wheel rotated by said piston-cylinder assembly and means is provided to lock and unlock the rotation of said worm wheel.