US1925215A - High-speed shaping machine with hydraulic drive - Google Patents

Description

p E., STURM 1,925,215

HIGH SPEED SHAPING MACHINE WITH HYDRAULIC DRIVE Filed May 28, 1930 4 Sheets-Sheet l /n venfor':

Sept. 5, 1933. E. STURM HIGH SPEED SHAPING MACHINE WITH HYDRAULIC DRIVE 4 Sheets-Sheet Filed May 28 Zffa/M E. STURM 1,925,215 HIGH SPEED SHAPING MACHINE WITH HYDRAULIC DRIVE Sept. 5, 1933.

Filed May 28 v4 Sheets-Sheet 3 I IIIIIIIIIII lnyenfon: FJh

Sept. '5, 1933.

E..STURM HIGH SPEED SHAPING MACHINE WITH HYDRAULIC DRIVE Filed May 28, 1930 SheetsSheet 4 Patented Sept. 5, 1933 UNITED STATES HIGH-SPEED SHAPING MACHINE WITH HYDRAULIC DRIVE Erwin Sturm, Stuttgart-Botnang, Germany Application May 28, 1930, Serial No. 458,848, and in Germany December 31, 1929 8' Claims.

The present invention relates to a hydraulically operated shaping machine and it consists primarily in the fact that the tool-carrying ram is driven by a pump with adjustable and reversible delivery and the work-carrying table is fed transversely by a hydraulic transmission gear coming into action intermittently.

In the further development of the invention the reversing of the pump driving the ram is obtained from a controlling slide, which is adjusted by a mechanical reversing device or feed gear box actuated by stops on the ram. For this purpose the controlling slide carries a groove, which controls the reversing lever of the pump.

A further development ofthe invention consists in inserting the part carrying the cam groove slidably in the controlling slide, to enable the working speed of the ram to be regulated thereby. The cam groove is preferably so shaped that only the speed of the working stroke is regulated, while the return speed remains unaltered.

Furthermore according to the invention, for the stopping of the machine, a disengaging lever is provided, which by means of a projection releases the feed gearbox when the cam groove has caused the pump to run light. In order to enable the machine to be stopped with any speed engaged, the midposition of the cam groove is constructed without inclination.

The reversal of the machine according to the present invention by altering the direction of delivery of the pump presents important advantages as compared with the reversal by a special reversing slide. The reversal is completely free from shock, since the ram is smoothly braked to a standstill by the pump, because when reversing the pump the delivery thereof is brought to zero during the first part of the reversing path and is connected for the second part in the new direction of delivery, rising from zero to the delivery quantity adjusted. This shock-free reversal enables considerably more strokes per minute to be adopted than would be possible when employing a separate reversing slide. Furthermore the reversal by the pump itself yields simpler pipe lines, with but few packings, as well as the omission of the packing of the reversing slide, which is always diflicult at high pressures.

The reversal by changing the direction of delivery of the pump also permits in the simplest manner of the adoption of a return accelerated to' any desired extent, since for this purpose it is only necessary to give the pump an appropriate return output for the return stroke.

It is an advantage in machines according to the invention to give the pressure piston equally large piston areas at both ends. In this way a uniform circulation of motive fluid and a satisfactory ventilation are obtained, since the quantity of motive fluid returning to the pump is always equal to the quantity of motive fluid delivered by the pump, so that the pump is always working with full admission.

Furthermore according to the invention, from the slide that controls the pumps, the control of a special hydraulic transmission gear effecting the feeding of the work-carrying table is also obtained, this hydraulic transmission gear being equipped with a throttling device, which on the one hand permits 01 diflerent admissions to the hydraulic motor of the gear for the purpose of regulating the speed of feed, and on the other hand effects an intermittent admission to the motor during the return of the ram.

One constructional form of the invention is illustrated by way of example in the accompanying drawings. Here,

Figures 1 and 2 are opposite side views of the machine, Figure 1 being partially in section,

Figure 3 shows the upper part of the machine, as seen from the back, on a larger scale,

Figure 4 shows the controlling device, partly in section,

Figure 4a is a plan of a detail,

Figures 411, 4c and 4d show the switch box in three different positions on a larger scale,

Figure-5 is a section on the line V--V in Fig. 4,

Figure 6 is a section on the line VI-VI in Fig. 4,

Figure '7 is a section on the line VII-VII Fig. 4,

Figure 8 shows the feed gear in longitudinal section on the line 8-8 in Figure 9 and,

Figure 9 in cross section, with the throttling device and the adjusting device for the feed,

Figure 10 is a side view of the control lever,

Figure 11 is a sectional elevation corresponding to part of Figure 8, but showing the reversing valve of the transverse table feed on a larger scale, with the rotatable valve member in a difierent position;

Figure 12 is a sectional elevation 01' the reversing valve on the line 12-12 in Figure 9, with the rotatable valve member in the same position as in Figure '8; and 1 Figure 13 is a view similar to Figure 12, but with the rotatable valve member in the same position as in Figure 11.

To the standard 1 is secured a cylinder 2, in

which there moves a pressure piston 3. The I pressure piston 3 is supported with the ends of the piston rods 4 and 4' against the ram 5, which carries the tool box, and is so supported as to be horizontally slidable in the standard. On the standard 1 there is furthermore a pump 6, which is driven by an electric motor or a belt. The pump 6 is in a known manner so constructed that the quantity delivered thereby is adjustable from zero up to a maximum value, and the direction of delivery is reversible. It is connected by two pipes 7 and 7' to the two ends of the cylinder 2. The member of the pump 6 serving for adjusting the quantity delivered and for reversing the direction of delivery is provided with a pin 8 (Figure 3), which projects out of the pump casing and is brought into connection with a lever 9, secured upon a shaft 10. Upon this shaft is mounted on the other side of the standard 1 a lever 11, which engages by a pin 12 in a cam groove 14 in a slide piece 13. By adjusting the slide piece 13, the levers 9 and 11 are shifted in consequence of the obliquely and discontinuously extending cam groove 14, and the adjusting of the pump to a different output, as well as the reversal thereof, are thereby effected.

In order to enable the speed of the cam to be regulated by adjusting the pump to different delivery outputs, the slide piece 13 is adjustably supported in a longitudinal slot 15 in a fiat slide 16, which is displaceably supported in a cover 17 secured to the frame. The adjustment of the slide piece 13 is effected by a positioning spindle 18, which passes by means of a screw thread 18' through the narrower downward projecting part 13' on the slide piece 13. The spindle 18 engages in a bush 19, which is supported on the cover 17, and which can be set in rotation from a handwheel 20 by means of a worm 21 and worm-wheel 22. For this purpose the spindle 18 is so connected with the bush 19 by the key 23 as to be non-rotatable but axially displaceable therein. By shifting the cam groove 14 the pump 6 can be adjusted for the speed of cutting needed at any time for the forward stroke.

The slide 16 is reeiprocated with a fixed stroke from the enclosed gear box known in high-speed planers by means of a crank 24.

The reversing device is actuated by two stops 25 and 25', adjustably fitted to the ram 5. These stops each co-operate with a slide, 26 and 26 respectively, which are so supported as to be slidable one over the other in a groove 6'7 in the control casing. Each of these slides has on one side teeth 68 and 68 respectively, which mesh with a toothed wheel 69 secured to the shaft 27. The lower slide 26 therefore engages with the toothed wheel to the right of the shaft 27, and the upper slide 26 to the left of the shaft, as shown in Figure 4a. If therefore the stop 25 meets the projecting slide 26, the latter is pressed back and the shaft 27 thereby rotated in a clockwise direction, but the upper slide 26 is moved outwards again against the ram 5. Upon the return of the ram the stop 25' comes into action and pushes the slide 26' back, whereby the control shaft 27 is rotated in a counterclockwise direction, and the other slide 26 is brought forward again into its operative position. The shifting of the shaft 27 is then transmitted by the toothed wheel 28 to a slide 30, which is supported in a guide 29, and which shifts the switch box to right or left.

The feed gear consists of a toothed ring 31, which is coupled with a worm wheel 32, which,

- so long as the pump 6 is running, is driven by a worm 34, mounted upon a shaft 33. In the interior of the toothed ring 31 is arranged a disc 35, rigidly connected with the crank 24, and on this disc is supported in a recess a double-armed pawl 36, one arm of which is able to engage in the internal teeth 31' of the ring of teeth 31, while the other arm is able to bear against stop surfaces and 30 on the slide 30 on diametrically opposite sides of the centre of the disc 35, which are exactly 180" apart. When these stops are not acting upon the pawl 36 its inner arm is brought by a spring 37 into engagement with the teeth 31', whereby the crank 24 is driven, and the slide 16 therebyv shifted, and with it the cam groove 14.

In Figures 4 and 4b the apparatus is shown in the position in which the pawl 36. owing to the stop 30', is out of engagement with the ring of teeth 31, and the slide 16 is in its left-hand end position, in which the pump is adjusted to maximum delivery quantity for the advance of the ram 5. Now as soon as the stop 25 strikes against the slide 26, the slide 30 is shifted to the right, as a result of which the pawl 36 is set free. and its other end, owing to the action of the spring 37, comes into engagement with the teeth 31' of the ring 31. Since this ring revolves continuously it takes the disc with it, as shown in Figure 40, with the pin 24 mounted thereon. as a result of which the slide valve 16 is shifted to the right. The shifting amounts however only to 180 degrees, because owing to the shifting of the slide 30 the left-hand stop surface-30" has come into the path of'the pawl 36, and in this position the coupling between the ring of teeth 31 and the crank is released again, as shown in Figure 4d. The crank pin 24 has therefore been rotated through 180 degrees, and the slide 16 has thereby been brought into the other end position.

During this movement the pin 12 slides in the control groove 14 in such a way that it switches the pump through zero delivery to return motion, so that the pump returns the ram at maximum delivery quantity until by the ram stop 25 the slide 30 is thrown over to the left again, and the switch box is returned out of the position shown in Figure 411 into the position shown in Figure 4?).

Now the adjusting of the speed of the ram is effected by shifting the position of the slide piece carrying the cam groove 14 in the slide 16, so that the lever 11 influenced by the cam groove is rotated to a greater or less extent out of the position that determines the idle running of the pump. If the pin 12 is located for example in the central stepped portion of the cam groove 14 the pump runs idly and the drive of the ram is interrupted. It is therefore possible, by shifting the handwheel, to alter the forward-speed of the ram uniformly from zero to a maximum value.

If the machine is to stop, and the pump 6 is not to deliver, it is then necessary to shift the slide 16 only so far that the pin is located in the central notch of the cam groove 14 corresponding to zero delivery. In order to attain this, round a shaft 39 beside the gear box is fitted a lever 40 with a stop surface 40', which, in the position shown in Figure 4, releases the pawl 36 after only 90 degrees rotation, so that the slide remains stationary in the middle of its stroke. The lever 40 is shifted by means of a handle 41.

In order also to enable the reversal to be ef fected by hand there is supported on the frame 1 a shaft 42, which, being rocked by a hand lever 43, shifts the feed shaft 2'7 by means of toothed gearing 44, 44'.

The intermittent feed of the table 45 islikewise effected by hydraulic means. For this purpose, upon one side of the machine is fitted a hydraulic gear 46, which consists of a pump 47 and a motor 48. The pump is driven at a constant speed from the main pump shaft 49 through bevel wheels 50 and a worm gear 52' co-operating with a worm 52 on a shaft 51. The movement of the table 45 is here obtained from the shaft 48 of the motor 48 in the known manner which is usual in shaping machines. In the present instance the shaft 48' drives a feed screw, not further illustrated, which is co-axial with it, and which meshes in a known manner with a nut or internal screw thread in the table 45, and, as it rotates, moves the table along the slide track 70. In order to obtain the intermittent table feed it is necessary to let the pump 4'7 run light during the ram stroke, while it feeds the motor 48intermittently during the return of the ram and drives it according to the desired table feed. In order to render this possible there is interposed, in the motive fiuid passages provided between the pump and the motor, a hollow rotatable valve member 53, which is divided by a partition into a pressure chamber 54 and a suction chamber 55. According to the position of the hollow rotatable valve member 53, either the passage 56 is connected to the pressure side '72 of the pump as shown in Figure 12 and the passage 57 to the suction side 71, as shown in Figure 8, or conversely the passage 56 is connected with the suction aperture '71 of the pump, as shown in Fig.

11, and the passage 57 with the delivery aperture 72 of the pump, as shown in Figure 13, so that the liquid motor 48 runs either toright or left. The reversal is effected by means of a hand lever 58, which is rigidly connected with the rotatable valve member 53. 1

In order to obtain the intermittent driving of the motor there is in the partition of the hollow rotatable valve member 53 an aperture 59, which establishes a connection between the suction and pressure chambers of the pump when the spindle 60, which is axially displaceable in the hollow rotatable valve member, sets this aperture free. In this case the pump runs idly and the motor stands still. If however this spindle closes the aperture 59, the motor is driven in one direction or the other according to the position of the hollow rotatable valve member.

Now the shifting of the spindle 60 is likewise effected from the slide 16 moved by the switching device. For this purpose there is fitted to it a switch nose 61, shown in Figures 4, 5 and '7. In switching for the return of the ram the nose 61 on the slide 16 pushes back a spring bolt 62,

which is slidably supported in the cover 17 as' shown in'Figure 5, and this spring bolt rocks a lever arm 63, shown in Figures 2, 4 and '7. The arm 63 is mounted fast upon a positioning shaft 64, shown in Figures land 10. A second lever arm 65, also mounted fast on the shaft 64, is

therefore oscillated through the same angle as thearm 63.

The outer end of the spindle 60 passes through a collar formed in this arm 65, as shown in Figure 10, the spindle being formed with abutments bearing against the collar, so that when the shaft 64 is rotated through an angle in a clockwise direction (having regard to Figures 7 and 10) the spindle moves inwards, thereby closing the aperture 59.

To enable the magnitude of the feed to be varied by turning the head 66. Hence a greater or smaller amount of motive fluid circulates idly, and the speed of revolution of the motor is thereby regulated. From the motor the table feed is then effected by means of a guide spindle or the like.

What I claim is:-

1. A hydraulically operated shaping machine, comprising a hydraulic ram carrying the shaping tool, a pump for actuating the hydraulic ram, a work-carrying table, means for adjusting the quantity of liquid delivered by the pump, a control slide for reversing the direction of delivery of the pump, a slide piece adjustably fitted to the control slide and formed with'a cam groove, a mechanical reversing device for shifting the control slide, stops on the ram for actuating the mechanical reversing device, a pin engaging in the cam groove and adapted to be displaced therein when the stops on the ram cause the.

quantity of liquid delivered by the pump, a control slide for reversing the direction of delivery of the pump, a slide piece adjustably' fitted to the control slide and formed with a cam groove, amechanical reversing device for shifting the control slide, stops on the ram for actuating the mechanical reversing device, a pin engaging in the cam groove and adapted to be displaced therein when the stops on the ram cause the mechanical reversing device to shift the control slide, transmission means actuated by the pin and adapted to connect the pump for advance, idle running and return as required, and means for adjusting the position of the slide piece on the control slide and thereby regulating the speed of the ram, the cam groove being so shaped that upon the slide piece being shifted only the speed of advance is regulated, while the speed of return remains unaltered.

3. A hydraulically operated shaping machine, comprising a hydraulic ram carrying the shaping tool, a pump for actuating the hydraulic ram, a work-carrying table, means for adjusting the quantity of liquid delivered by the pump, a control slide for reversing the direction of delivery of the pump, a mechanical reversing device for shifting the control slide, stops on the ram for actuating the mechanical reversing device, liquid gear consisting of a pump and a'motor controlled by the control slide for feeding the workcarrying table in a direction transverse to the direction of reciprocation of the tool, and a throttling device arranged between the pump and the motor of the liquid gear, the said throttling device being adapted in one adjusted position to short-circuit the motive fluid delivered by the pump entirely, in another adjusted position to by-pass the said motive fiuid partially, and in another adjusted position to feed the motor fully.

4. A hydraulically operated shaping machine, comprising a hydraulic ram carrying the shaping tool, a pump for actuating the hydraulic ram, a work-carrying table, means for adjusting the quantity of liquid delivered by the pump, a control slide for reversing the direction of delivery of the pump, a mechanicalv reversing device for shifting the control slide, stops on the ram for actuating the mechanical reversing device, liquid gear consisting of a pump and a motor controlled by the control slide for feeding the work-carrying table in a direction transverse to the direction of reciprocation of the tool, a reversing slide. a throttling valve fitted into the reversing slide and interposed between the pump and the motor of the liquid gear, the said throttling valve being adapted in one adjusted position to short-circuit the motive fluid delivered by the pump entirely, in another adjusted position to by-pass the said motive 'iluid partially, and in another adjusted position to feed the motor fully. and a stop on the control slide for controlling the throttling valve;

5. A hydraulically operated shaping machine, comprising a hydraulic ram carrying the shaping tool, a pump for actuating the hydraulic ram, a work-carrying table, means for adjusting the quantity of liquid delivered by the pump, a control slide for reversing the direction of delivery of the pump, a mechanical reversing device for shifting the control slide, stops on the ram for actuating the mechanical reversing device. liquid gear consisting of a pump and a motor controlled by the control slide for feeding the work-earrying table in a direction transverse to the direction of reciprocation of the tool, a reversing slide, a throttling valve fitted into the reversing slide and interposed between the pump and the motor of the liquid gear, the said throttling valve being adapted in one adjusted position to short-circuit the motive fluid delivered by the pump entirely, in another adjusted position to by-pass the said motive fluid partially, and in another adjusted position to feed the motor fully and being further adapted to have its initial position adjusted by hand to regulate the magnitude of the feed,

and a stop on the control slide for controlling the throttling valve.

6. A hydraulically operated shaping machine, comprising a hydraulic ram carrying the shaping tool, a pump for actuating the hydraulic ram, a control slide for reversing the direction of delivery of the pump, two stops on the ram, two superposed sliding members, adapted respectively to be displaced by the said stops, one at one end of the stroke of the ram and the other at the other end, a toothed rack on each of the sliding members, a toothed pinion located between the racks and meshing with both of them, so that when one sliding member is displaced by a ram stop the other is returned into the path of the other ram stop, and means actuated by the toothed pinion for reciprocating the control slide that reverses the pump.

7. A hydraulically operated shaping machine, comprising a hydraulic ramcarrying the shaping tool, a pump for actuating the hydraulic ram, a control slide for reversing the direction of delivery of the pump, a crank pin for reciprocating the control slide, a rotatable disc carrying the crank pin, a continuously rotating internally toothed ring concentric with the said disc, a pawl mounted on the disc and adapted to engage with the teeth of the said ring to cause the disc to be rotated by the ring. a spring tending to keep the pawl engaged with the teeth, two movable abutments at opposite ends of a diameter of the disc, adapted when moved into the path of the pawl to disengage it from-the toothed ring, a reciprocating slide carrying the two abutment-s and adapted to move them into the path of the pawl alternately, so that whenever one abutment is withdrawn the disc rotates half a revolution and is then stopped by the other abutment, stops on the ram, and means actuated by the stops for reciprocating the said slide every time the ram reaches the end of its stroke in either direction.

8. A hydraulically operated shaping machine as claimed in claim '7, further comprising a third abutment adapted to be moved by hand into the path of the pawl midway between the other two abutments, to release the pawl and thereby bring the control slide to a standstill in the middle of its stroke.

ERWIN STURM.

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