US3018591A - Device for the working in stages of the surfaces of workpieces on a grinding or polishing train - Google Patents

Description

1962 w. WROBBEL 3,018,591

DEVICE FOR THE WORKING IN STAGES OF THE SURFACES 0F WORKPIECES ON A GRINDING 0R POLISHING TRAIN Filed June 9, 1958 3 Sheets-Sheet 1 INVENTOR.

Jan. 30, 1962 w. WROBBEL 3,013,591

DEVICE FOR THE WORKING IN STAGES OF THE SURFACES OF WORKPIECES ON A GRINDING 0R POLISHING TRAIN 1 Filed June 9, 1958 3 Sheets-Sheet 2 INVENTOR.

%rn er 44% BY Jan. 30, 1962 w. WROBBEL 3,018,591

DEVICE FOR THE WORKING IN STAGES OF THE SURFACES OF WORKPIECES ON A GRINDING 0R POLISHING TRAIN 3 Sheets-Sheet 3 Filed June 9. 1958 Pie. 7

INVENTOR. WM A rvW fiffa r 1 7 9 3,018,591 a I DEVICE FOR THE WORKING IN ;STAGES OF THE SURFACES OF WORKI'IECES ON A GRINDING OR POLISHING TRAIN p Werner Wiobb'el, Nurtinge'n, Germany, assigns: to Firnia Metahowe rk Class, Ranch & Schnizler K.G., Nuirtin gen, Wurttemberg, Germany Filed June 9. 1958, Ser. No. 740.807 Claims priority, application Germany June 15, 1957 11 Claims. (Cl. 51-217) This invention relates to a method and device for the working in stages of the surfaces of workpieces on a grinding or polishing train, the workpieces being conducted on a conveying truck each past a plurality of work ing machines. The working of the surfaces which occur regularly in sufiiciently large numbers is carried out in an economic manner on so-called grinding or polishing trains. These consist of a number of grinding or polishing machines, which are arranged on a conveying Way for the workpieces, These machines are in such cases so constructed that their head, with drive device, working spindle mounting and tool, for example grinding or polishing wheel, is arranged for vertical adjustment on a column, and can be set for the working operation in each case, and in fact in each case one stage of machining is carried out on the workpiece passing by on each machine. In the case of workpieces with plane surface, such as decorative strips or the like, the individual working stages can be set rigidly with their tools and the workpieces can be drawn through beneath these tools in a simple rectilinear movement. If on the other hand the surfaces of the workpieces are profiled, the-procedure is adopted in the known polishing or grinding trains, that the head of each of the individual Working machines is moved in relation to the passing workpiece. For this purpose copy rulers are used, which must very precisely imitate the section of the workpiece surface to be machined, and the movement of the head is controlled hydraulically, pneumatically or electro-magnetically. This requires a very complicated and expensive control arrangement, and nevertheless often leads to unsatisfactory working results.

These disadvantages are avoided according to the invention in a simple and advantageous manner, due to the fact that the conveying trucks carrying the workpieces are so moved in every working stage in relation to the tool of each working machine, which is stationary in relation to them but is driven, additionally to their advancing movement and during this movement, by raising, lowering, inclining, tilting or rotation, that the part of the workpiece surface to be machined in each case comes to bear on the tool or is lifted from the tool. While, in the known process, in the machining the heads of the working machines are moved, in the case of the process according to the invention they are stationary in relation to the workpieces to be machined, and these are rather brought up to the tools and removed again. This movement can he carried out in a substantially simpler manner than that of the machine heads, and thus leads to a considerable reduction in expense of the entire plant. 7

A device for carrying out the method in accordance with the invention, with a frame and a guide-way arranged thereon and consisting of rails for a number of conveying trucks, which are couplable with an advancing device, can advantageously be so constructed in accordance with the invention that the running surfaces of the rails imitate in their course the course of the workpiece surface. The method in accordance with the invention accordingly needs for its carrying out a purely mechanical control and conveying arrangement for the grinding and polishing train, wherein the expensive structural elements are avoided, which are necessary in the case of a hydraulic, pneumatic or electro-mag'netic control arrangeatent amassi ment. In the object of the invention the control, which is necessary in the case of the machining of irregularly shaped workpieces, is taken over by guide-ways, which so move the workpiece that the tools of the working machines, for example the grinding or polishing wheel's, remain in engagement with the workpiece surface, without variation of the vertical setting of the tools. 7

The guide-ways possess the length of the conveying arrangement, and can be differently constructed in every Working position. Their construction can take place Without great precision if the workpiece is clamped on resilient mountings or the grinding or polishing wheel is resiliently supported. According to the constructon of the guideways the workpiece can also be pressed with diiferent pressures in different sections against the grinding or potishing wheel, or the engagement of the wheel can be iiiterrupted. Even the grinding of projections or edges to exact points is possible. I

The conveying device of the object of the invention can advantageously he so constructed that every conveying truck consists of an under part and a workpiececarrying upper part movable in relation thereto, its own guide-Way being allocated to each part. The lower part of the conveying truck can here expediently be couplable with the advancing device and the upper part can be so mounted on the under part that on the one hand it participates in the advancing movement of the under part and on the other hand it is shiftable perpendicularly of this movement as Well as being rotationally movable in all directions. For this purpose the guide-way of the under partof the truck can have a rectilinear course, and that of the upper part of the truck can be made to imitate the form of the workpieces. Furthermore the upper part of the truck can advantageously run with two pairs of wheels on the guide-way, and each wheel can have its own rail. v

The conveying trucks themselves can advantageously be so constructed in accordance with the invention that the spacing between the upper part and the lower part is variable from working site to working site. For workpieces of different forms a plurality of upper parts dilfering from one another in their assembly can be used with one and the same lower part, due to the fact that a plurality of diiferently designed upper truck parts are interchangeably mounted on the lower truck part.

For the machining of greatly curved workpieces the conveying trucks can advantageously be so constructed that the upper parts of the trucks are provided with a clamping arrangement for the workpieces, and this arrangemeiit, with the clamped-in workpiece, is movable, for example rotatable, in relation to the upper part of the truck. For this purpose a control rail and an arm can be provided, in which arm a guide roller running on the control rail is mounted.

In accordance with the invention the work piece can advantageously also be moved transversely of the guideway, due to the fact that in the region of the tool a carriage with sections of the guide rails mounted thereon is movable in the guide-way by means of stops such for example as rollers, which are mounted on the under part of the truck and rest on guide rails of the carriage, transversely of the direction of travel and of the endless belt driving the under part of the truck, and the upper truck 'part running on the guide rails is connected in transversely movable fashion with the under part of the truck. The carriage can here expediently be held in the rest position by return springs, and the upper part of the truck can be guided with a transversely disposed slot on a bolt projecting from the under part of the truck.

The invention is illustrated by Way of example by reference to details of the device for carrying out the method in accordance with the invention in the accompanying drawings, wherein:

FIGURE 1 shows a conveying arrangement with an extended workpiece, in front elevation,

FIGURE 2 shows a lateral elevation thereof,

FIGURE 3 shows a laterally tilted conveying arrangement, again in front elevation,

FIGURE 4 shows a lateral elevation thereof,

FIGURE 5 shows a conveying arrangement with a curved workpiece, again in front elevation,

FIGURE 6 shows a lateral elevation thereof,

FIGURE 7 shows a conveying arrangement movable transversely of the guide-way, in a front elevation, and

FIGURE 8 shows a plan view thereof.

In the drawings, 1 designates a frame constructed in suitable fashion and consisting of a plurality of sections, which are preferably similar. These are allocated in each case to a grinding and polishing machine (not shown) of suitable construction. They are firmly connected with one another, and in their entirety form the guide-way of a grinding and polishing train, which is provided at one end with a drive device for an endless belt or chain moving the conveying trucks of the train and at the other end with a reversing device for the conveying trucks. On the frame 1 there is arranged a roll-way 2, consisting of two pairs of rails. The individual rails of this roll-way 2 lie horizontally and are secured parallel to one another at a specific interval. Between them there run rollers 3, which are mounted on spindles 4. These pertain to an under part 5 of the conveying truck, which is couplable with the endless belt (not shown in FIGURES l to 6), and is driven by this belt. The rollers 3 have some clearance from the upper rails of the roll-way 2.

- On the under part of the truck, 5, there are mounted two spars 6 and 7, each carrying a slot. Through each of these there is pushed a bolt 8 and 9, which are arranged in the ends of the upper truck part 10. The upper part of the conveying truck is connected by the spars 6 and 7 and the bolts 8, 9 with the under part 5, for example by means of stop nuts mounted on the bolts 8, with security against. thrust and traction, and is driven by the under pant 5 in the direction of the arrow. The upper part 10 can here be offset laterally in relation to the under part 5, and also inclined in the direction of movement. In the upper truck part 10 there are arranged two axles 11 and 12 of different lengths, upon each of the ends of which there is rotatably mounted a roller 13 and 14. These rollers 13, 14 run on two pairs of rails 15 and 16, which are secured on the frame 1 and the running edges of which In the case of the form of embodiment of the object of the invention as shown in FIGURES 1 to 4, a holding arrangement 17 for the workpiece 18 to be machined is arranged on a mounting portion of the upper truck part 10, the workpiece having an extended form in the case of these forms of embodiment. By the holding arrangement 17 the workpiece 18 is firmly connected with the upper truck part 10, and positively follows the movements thereof. An additional intermediate member may if necessary be provided in the holding arrangement.

Since the upper truck part 10 is only connected with the under part 5 as regards thrust and traction, the workpiece 18 can be moved and controlled in every plane through the guide rails 15, 16. The running edges of the rails 15, 16 are adapted to the shape of the workpiece 18 and are so arranged that the latter is pressed against the tool 19 of the grinding and polishing machine in every position during the advancing movement. In order to render lateral deviation of the upper truck part 10 with the workpiece 18 in relation to the tool 19 impossible, the rollers 13, 14 are so constructed that they are provided with a groove, expediently wedgeshaped in crosssection, the flanks of which rest against the guide rails 15, 16.

The rails of the rail pairs 15, 16 may be made similar within the pairs. In this case the upper truck part 10 is only moved in a vertical plane lying in the direction of advancement. In order also to incline the upper truck part 10 laterally, differences in the height of the running edges must exist, as represented in FIGURE 3, between the rails 15, 15 and 16, 16' of each pair.

As may be seen from FIGURES 5 and 6, in the case of curved workpieces 20 the holding arrangement for these may be so constructed that the workpieces 20 are pivotable during the advancing movement of the upper truck part 10 about a horizontal axis lying transversely of this part. For this purpose the upper truck part can consist of a first part 21, which is mounted on the under part 5 for hingeing about a spindle 22 lying in the direction of advancement. On part 21 there is mounted a mounting part 23 carrying two holding arrangements 24 for the workpiece 20. Furthermore the lower part 21 carries the axle 11, which may be divided, and the rollers 13, which run on the pair of rails 15. On the mounting part 23 there is firmly mounted an arm 25 of lever form, carrying a cam follower roller 26 at its free end. This roller runs on a rail 27, which has cams of such a shape that the arm 25 is pivoted in the direction of the arrow during the advancing movement of the part, and in this movement the mounting part 23 with the holder 24 and the workpiece 20 is so rotated thereby that the machined surface always rests on the tool 19, which rotates oppositely t0 the direction of advancement.

In the case of the form of embodiment as illustrated in FIGURES 7 and 8 of the device for the carrying out of the method in accordance with the invention the conveying arrangement carrying the workpiece '18 can be shifted transversely of the direction of advancement and of the tool 19. The workpiece consists in this case for example of the grill of a motor vehicle radiator, of frame shape and curved on one side.

On the frame 1 there are arranged, transversely of the direction of advancement, pairs of rails 28, 29, and on them a carriage 30 is movable due to the fact that it is guided with rollers 31 between the pairs of rails 28, 29. This carriage 30 is subject to the influence of two return springs 32, which are stretched with equal initial tension between the frame 1 and the carriage 30, and hold the carriage 30 fast in its rest position as illustrated in the drawing. Upon the surface of the carriage 30 there are arranged, in the extension of the guide rails 15, 16, rail sections 15, 16'. In the middle of the surface of the rails, in the direction of advancement, there is provided an aperture, and curved guide rails 33 are arranged on both sides thereof. The course of these guide rails 33 determines the lateral displacement of the carriage 30, and must therefore be adapted to the course of the workpiece 18 to be machined. Against these guide rails 33 there rest rollers 34, which are mounted on the lower truck part 5. The latter is in engagement with a conveying chain 35, which rotates in the direction of the arrow 36 and drives the lower truck part 5. The latter carries an upwardly projecting bolt 37, which pierces the upper truck part 10 in a transversely disposed slot 38. Since the upper truck part 10 runs in correct track through its guide rollers 13, 14 on the rails 15, 16 and the rail sections 15, 16', it is shifted in the region of the carriage 30 in relation to the lower truck part 5 with the carriage 30, transversely of the direction of advancemnt, without its connection with the lower truck part 5, which effects the advancement, being interrupted.

I claim:

1. Workpiece conveying arrangement, comprising, in combination, support means; rail means mounted on said support means, said rail means having in longitudinal direction thereof different cam portions; first truck means guided along said support means for movement in direction of said rail means, said first truck means having a portion located adjacent said rail means; second truck means mounted on said portion of said first truck means for movement with the same in said longitudinal direction, said second truck means having a mounting part turnable about two axes transverse to each other, said second truck means including follower means in engagement with said cam portions of said rail means; holding means mounted on said mounting part of said second truck means for holding a workpiece in engagement with stationary machining tool means; and means for moving said first truck means with said second truck means and said workpiece holding means in said longitudinal direction so that said mounting part of said second truck means turns about said two transverse axes when said follower means move along different cam portions of said rail means so that a surface of the workpiece having a contour corresponding to said cam portions is held in contact with machining tool means.

2. Workpiece conveying arrangement, comprising, in combination, support means; a pair of rail means mounted on said support means, said rail means having in longitudinal direction thereof dilferent cam portions; first truck means guided along said support means for movement in direction of said rail means, said first truck means having a portion located between said rail means; second truck means having a first part mounted on said portion of said first truck means for turning movement about a first axis, and a mounting part mounted on said first part for turning movement about a second axis transverse to said first axis, each of said parts of said second truck means having cam follower means in engagement with said cam portions of said rail means; holding means mounted on said mounting part of said second truck means for holding a workpiece in engagement with stationary machining tool means; and means for moving said first truck means with said second truck means and said workpiece holding means in said longitudinal direction so that said parts of said second truck means turn about said transverse axes when said cam follower means move along different cam portions of said rail means so that a surface of the workpiece having a contour corresponding to said cam portions is held in contact with machining tool means.

3. Workpiece conveying arrangement, comprising, in combination, support means; a pair of rail means mounted on said support means, said rail means having in longitudinal direction thereof different cam portions; first truck means guided along said support means for movement in direction of said rail means, said first truck means having a portion located between said rail means; second truck means mounted on said portion of said first truck means for movement with the same in longitudinal direction and turnable about a longitudinal axis, said second truck means including follower means in engagement with said rail means; holding means mounted on said second truck means for holding a workpiece in engagement with stationary machining tool means, said holding means including a shaft turnable on said second truck means about an axis transverse to said rail means, a lever fixed on said shaft; an additional rail extending parallel to said rail means and having cam portions, the free end of said lever of said holding means being in contact with said additional rail; and means for moving said first truck means with said second truck means and said workpiece holding means in said longitudinal direction whereby said second truck means turns about said longitudinal axis when said follower means move along different cam portions of said rail means and whereby said holding means turns about said transverse axis under control of said additional rail so that a surface of the workpiece having a contour corresponding to said cam portions is held in contact with machining tool means.

4. Workpiece conveying arrangement, comprising, in combination, support means; a pair of rail means mounted on said support means, said rail means having in longitudinal direction thereof different cam portions; first truck means. guided along said support means for movement in direction of said rail means, said first truck means having a portion located between said rail means; second truck means including longitudinally spaced pairs of wheel means in. rolling engagement with said rail means; mounting means connecting said second truck means with said portion of said first truck means for movement with the same in said direction, at least partly tiltable in longitudinal direction so that leading and trailing end portions of said second truck means can move away from and toward said first truck means, respectively, and turnable about an axis extending in longitudinal direction; holding means mounted on said second truck means for holding a workpiece in engagement with stationary machining tool means; and means for moving said first truck means with said second truck means and said workpiece holding means in said longitudinal direction whereby said second truck means turns about said longitudinal axis when said follower means move along different cam portions of said pair of said rail means and is longitudinally tilted when said pairs of wheel means engage longitudinally spaced difiierent cam portions of said rail means so that a surface of the workpiece having a contour corresponding to said cam portions is held in contact with machining tool means.

5. Workpiece conveying arrangement, comprising, in combination, elongated support means; a carriage mounted on said elongated support means for movement in transverse direction; a first pair of rail means mounted on said carriage and extending in longitudinal direction of said elongated support means, said rail means having in longitudinal direction thereof different cam portions; a second pair of rail means mounted on said carriage extending in said longitudinal direction and having cam portions extending in transverse direction; first truck means guided along said suppot means for movement in direction of said rail means, said first truck means having a portion located between said rail means; second truck means mounted on said portion of said first truck means for movement with the same in said longitudinal direction and turnable about a longitudinal axis, said second truckv means including first follower means in rolling engagement with said first pair of rail means, and second follower means in engagement with said second pair of rail means; holding means mounted on said second truck means for holding a workpiece in engagement with stationary machining tool means; and means for moving said first truck means with said second truck means and said workpiece holding means in said longitudinal direction whereby said second truck means turns about said longitudinal axis when said first follower means move along said cam portions of said first rail means and whereby said carriage with said first rail means, said second truck means and with said workpiece holding means move in said transverse direction under the control of said cam portions of said second rail means so that a surface of the workpiece having a contour corresponding to said cam portions is held in contact with machining tool means.

6. Workpiece conveying arrangement, comprising, in combination, support means; an inner pair of rail means and an outer pair of rail means mounted on said support means, said outer rail means being parallel to said inner rail means, each pair of rail means having in longitudinal direction thereof different cam portions; first truck means guided along said support means for movement in direction of said rail means, said first truck means having a portion located between said rail means; second truck means mounted on said portion of said first truck means for movement with the same in said direction, at least pa'tly tiltable in longitudinal direction so that leading and trailing end portions of said second truck means can move away from and toward said first truck means, respectively, and turnable about a longitudinal axis, said second truck means including a first pair of wheel means and a second pair of wheel means respectively in rolling engage- 'ment with said inner and outer rail means and being longitudinally spaced from each other; holding means mounted on said second truck means for holding a workpiece in engagement with stationary machining tool means; and means for moving said first truck means with said second truck means and said workpiece holding means in said longitudinal direction whereby said second truck means turns about said longitudinal axis when said follower means move along difi'erent cam portions of said rail means so that a surface of the workpiece having a contour corresponding to said cam portions is held in contact with machining tool means.

7. A workpiece conveying arrangement as set forth in claim 6, wherein said first pair of wheel means are front wheels and in engagement with said inner pair of rail means, and wherein said second pair of wheel means are rear wheels in engagement with said outer pair of rail means.

8. Workpiece conveying arrangement, comprising, in combination, support means; a pairof rail means mounted on said support means, said rail means having in longitudinal direction thereof different cam portions; first truck means guided along said support means for movement in direction of said rail means, said first truck means having a portion located between said rail means; second truck means including longitudinally spaced pairs of wheel means in rolling engagement with said rail means; mounting means connecting said second truck means with said portion of said first truck means for movement with the same in said direction, at least partly tiltable in longitudinal direction so that leading and trailing end portions of said second truck means can move away from and toward said first truck means, respectively, and turnable about an axis extending in longitudinal direction; said mounting means including slotted members secured to said first truck means, shaft means secured to said second truck means extending in longitudinal direction and pass ing through said slotted members, and stop means on said shaft means engaging said slotted members to prevent movement of said shaft means and said second truck means in longitudinal direction relative to said first truck means; holding means mounted on said second truck means for holding a workpiece in engagement with stationary machining tool means; and means for moving said first truck means with said second truck means and said workpiece holding means in said longitudinal direction whereby said second truck means turns about said longitudinal axis when said follower means move along different cam portions of said rail means of said pair of said rail means and is longitudinally tilted when said pairs of wheel means engage longitudinally spaced different cam portions of said rail means so that a surface of the workpiece having a contour corresponding to said cam portions is held in contact with machining tool means.

9. Workpiece conveying arrangement, comprising, in combination, support means; a plurality of pairs of rail means mounted on said support means, said pair of rail means being longitudinally aligned and having in longitudinal direction thereof different cam portions, the cam portions of each rail means being different; first truck means guided along said support means for movement in direction of said rail means, said first truck means having a portion located between said rail means; second truck means mounted on said portion of said first truck means for movement with the same in said longitudinal direction, said second truck means having a mounting part turnable about two axes transverse to each other, one of said axes extending in the longitudinal direction of said rail means, said second truck means including follower means in engagement with said cam portions of said rail means; holding means mounted on said mounting part of said second truck means for holding a workpiece in engagement with stationary machining to'ol means; and means for moving said first truck means with said second truck means and said workpiece holding means in said longitudinal direction so that said mounting part of said second truck means turns about said longitudinal and transverse axes when said follower means move along different cam portions of said rail means so that a surface of the. workpiece having a contour corresponding to said cam portions of said aligned pair of rail means is successively brought into contact with a plurality of machining tool means which are respectively associated with each of said rail means.

10. A workpiece conveying arrangement, comprising, in combination, support means; a pair of rail means mounted on said support means and having in longitudinal direction thereof different cam portions; first truck means guided along said support for movement in direction of said rail means and having a portion located between said rail means; second truck means located on said first truck means; means for mounting said second truck means on said portion of said first truck means for movement with the same, and turnable about a longitudinal axis and about a transverse axis, said second truck means including at least one pair of follower means respectively engaging said rail means, and being located on opposite sides of said longitudinal axis, and spaced in longitudinal direction from said transverse axis; holding means mounted on said second truck means for holding a workpiece; and means for moving said first truck means with said second truck means and said holding means in said longitudinal direction so that said second truck means turns about said transverse axis when said follower means simultaneously pass over projecting or depressed portions on said rail means, and turns about said longitudinal axis when said follower means simultaneously engage different cam portions of said rail means so that a surface of a workpiece having a contour corresponding to said cam portions may be held in contact with tool means.

11. A workpiece conveying arrangement, comprising, in combination, support means; a pair of rail means mounted on said support means and having in longitudinal direction thereof different cam portions; first truck means guided along said support for movement in direction of said rail means and having a portion located between said rail means; second truck means located on said first truck means; means for mounting said second truck means on said first truck for movement of the same in said direction and turnable about the longitudinal axis, said second truck means including a pair of follower means respectively engaging said rail means; holding means for a workpiece and mounted on said second truck means turnable about a transverse axis; follower lever means secured to said holding means for turning movement with the same about said transverse axis; other rail means having cam portions and extending along said pair of rail means, said other rail means being engaged by said follower lever means; means for moving said first truck means with said second truck means and said holding means in said longitudinal direction whereby said second truck means turns about said longitudinal axis when said follower means simultaneously engage different cam portions of said rail means, and so that said workpiece holding means turns about said transverse axis when said follower lever means engages cam portions of said other rail means so that a surface of a workpiece having a contour corresponding to said cam portions is held in contact with a tool.

References Cited in the file of this patent UNITED STATES PATENTS 588,637 Espinasse Aug. 24, 1897 1,848,470 Fohrenbach Mar. 8, 1932 1,891,279 Hank Dec. 20, 1932 2,015,720 Louviaux Oct. 1, 1935 2,217,545 Guenther Oct. 8, 1940 FOREIGN PATENTS 772,817 Great Britain Apr. 17, 1957

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