US2141647A - Milling machine for grain - Google Patents

Description

Dec. 27, 1938. .A. FREROTTE 2,1 1,647

MILLING MACHINE FOR GRAIN Filed July 2, 1957 4 Sheets-Sheet 1 I N V E N TO R Auausr; FREROTTE Arron/V536 Dec. 27, 1938. A. FREROTTE 2,141,647

' MILLING MACHINE FOR GRAIN Filed July'2, 1937 4 Sheets-Sheet 2 mvcwf R HUGl/STE FRERorrE A. FR EROTTE I Dec. 27, 1938.

MILLING MACHINE FOR GRAIN 4 Sheets-Sheet 3 I N V E N TO R Hum/51E FE'EEGTTE Filed July 2, 1957 HTTOIE'NEYS Dec. 27, 1938. A. FREROTTE' 2,141,647,

MILLING MACHINE FOR GRAIN Filed July 1937 4 Sheets-Sheet 4 INVENTOR fluausrs FREROTTE izu wr ATTORNEY:

Patented Dec. 27, 1938 UNITED s'rres MILLING MACHINE FOR GRAIN Auguste Frrotte, Liege, Belgium, assignor to Henry Simon Limited, Stockport, England, a

British company Application July 2, 1937, Serial No. 151,652 In Belgium July 25, 1936 Claims.

This invention is for improvements in or relating to a milling machine for grain of the kind comprising two milling rollers, one of which is rotatable about a fixed axis and the other of 5i; which is movable towards and away from the first said roller and a train of gears and pinions connecting together two gear-wheels fixed respectively to the two rollers. The movement of the roller is required for two purposes. It en- 1o ables the pressure on the material being ground to'be regulated and the extent of movement for that purpose is quite small. It also enables the rollers to be brought closer together after they have been reduced in diameter by re-bufilng or 1 re-grooving.

According to this invention, a milling machine of the kind referred to above is characterized in that the movable roller is so mounted and the pinion which meshes with the gear-wheel on the movable roller is so located that the short path of movement of the axis of the movable roller during the adjustment of the distance between the rollers, as hereinbefore described, is substantially parallel with or deviates little from a line parallel with the common tangent of the contacting pitch circles of said pinion and gearwheel. It will be appreciated that with this ar-- r-angement the variation inthe extent of mesh occasion d by the movement of the roller for adv justment of the pressure will be negligible and thus there will be little tendency for wear of the gear-teeth. It will further be appreciated that it is not usual to run the machine when the rollers are fully separated. If desired, smaller pitched teeth may be employed than usual.

In one arrangement of carrying out the invention, the movable roller and its gear-wheel may be mounted to swing about an axis disposed on the opposite side of the roller axis to that on which is-located the gear pinion which engages the roller gear-wheel, which axis of swing, axis of the movable roller and the axis of the pinion gear-wheel lie substantially line when the gear-wheel and pinion are in full mesh, which 45, line is substantially at right angles to a line joining the axes of the two rollers.

Another feature of the invention consists in locating said gear-wheels and gear-pinions-in a casing comprising separable upper and lower 50, parts, the lower of which parts comprises an oilwell into which a part of the gearing clips and which is pivotally secured to the upper casing and in the provision of means for so locating the lower part: in an open position that the oil'is V 55gretained therein. One of said 'gearepinions-may be driven directly by anelectric motor which is carried by said casing.

Yet a 'further feature of the invention, in-a milling machine wherein two pairs of milling rollers are provided, for-example parallel with one another, consists in that the two pairs of rollers are driven respectively by two motors. The two trains of gears and the two motors may all be arranged at one end of the machine.

In a milling machine in which hand-controlled means are provided for varying the distance apart oisaid rollers and in which an electric motor is arranged to drive said rollers, a feature of the invention consists in the provision of a switch in circuit with the motor and so operated by said hand-controlled meanst'hat the circuit is closed when the rollers are brought together. For example, the'switch-is closed when the rollers are brought together; Conversely, the switch is opened when the-rollers are moved apart.

In an arrangement in which the movement of the movable roller is efiected by an operating arm which extends out through a slot in the casing surrounding the rollers, -a feature of the invention consists in providing said arm with a shield which is arranged to obscure said slot for all positions of said arm.

' "The followingis a description of one form of construction for a milling machine reference being made to the accompanying drawings, in which:

Figure 1 is an end elevation of a machine having two pa-irs of rollers, on one side of the machine a casing containing the gearing being shown in section, while on the other side of. the machine the top* part of the gearing casing has been removed while the'lower part has been swung downwardly,

Figure '2 is a vertical section through the casing and in a plane passing through the slot in which the control lever operates,

Figure 3 is a plan view of the hand control means shown in Figure 2 showing parts thereof in section on the line 33, and

Figure 4 is a section on the line 4- of Figure 2. throughthe clutch mechanism.

As'will be seen from Figure 1, two pairs of independently-driven rollers are'provided in the one machine casing. It is usual in such an arrangement for'ra roller of one of the pairs to receivelits drive from a belt-pulley fixed to its shaft at one end of the machineandiora roller ofzthe other pair to receive its drive from a pulley'fixed to its shaft at the other-end ofvthe machine. It, is :alsosknown-to "connect theisecnd roller of each pair through a train of gears to the first said roller so as to provide a suitable speed ratio. In the present form of construetion it will be noted that both pairs of rollers receive their drive from the same end of. the machine.

Each pair of rollers comprises an upper roller 3 which is arranged to rotate about a fixed axis and a lower roller 2 which is so. mounted as to be capable of movement towards and away from the roller 3. The rollers are gear-connected together by a gearewheel l0 fixed to rotate with the roller 3, an intermediate pinion 8, a compoundintermediate pinion having one portion !2 gearing with the pinion 8 and another portion 9 gearing with a gear-wheel l4 fixed to rotate with the roller 2. The roller 2 and thegearwheel I4 are mounted to swing about an axis [8. This axis and the axes of the gear-wheel l4 and pinion 9 are arranged substantially in line when the two rollers are in contact, which line is ap-' proximately at right-angles to a line passing through the axesvof the two rollers. Thus, as the movable roller 2 is moved towards and away from the roller 3 to the small extent necessary to adjust the pressure on the material being ground, the path of movement of the axis of the roller 2 deviates but little from a line parallel with the tangent common to the contacting pitch circles of the gear-wheel I4 and pinion 9. The further the axis I8 is arranged from the axis of the roller 2, the more nearly will said path of movement be parallel to the common tangent.

It will be noted that the gear-train is enclosedin a two-part casing, the upper part I of which is fixed in relation to the machine frame and the lower part 5 of which casing is mounted to swing about a pivot pin 6'. The two parts of the casing are secured together by set-screws l9. When closed, the dividing line between the two parts of the casing is inclined to the vertical and a stop 20 is provided on the end wall of the machine to engage an abutment on the bottom part of the lower casing so that when it is swung downwardly the oil contained in'the lower part of the casing is retained therein. The compound pinion 9, l2 and the intermediate pinion 8 are M andthe gear-wheel l0, respectively, whenthe lower part of the casing is lowered. The upper part of the casing I can be detached from the main body of the machine; thus, when it is detached and when the lower part of the casing is swung downwardly, ready access may be gained to the gear-wheels and pinions for the purposes of cleaning and inspection. Furthermore, the arrangement enables the rollers to be withdrawn through apertures in the side wall of the main casing after the removal of the bearings for the roller shafts. Mounted on the lower part 5 of each casing is a driving motor 9a to a shaft of which is secured the pinion 5. As already indicated, the lower part of the casing forms an oil-bath into which the compound gear 9, l2

dips and thus distributes oil to the other wheels 7 of the gear-train. With this arrangement, both the driving motors and the transmission gears are arranged at oneend of the machine. As already indicated, the roller 2 and the gear-wheel Hi are arranged to swing about a pivot axis l8.

This is effected by'mounting them on a cranked lever 2| which at one end is pivotally mounted about the axis' 18 and the other end 'of which is forked and 'straddles a .r0d'22 having abut ments 23 and 24 arranged'on either side of the fork. The rod may be moved in an up-and-down direction by an eccentric, shown dotted, mounted on a cross shaft 25 (see Figure 2) to which is attached an operating lever I5. A fine adjustment for moving either end of the roller 2 is provided by a screw-and-nut mechanism associated with the rod 22 at each end of the machine and with abutments 23 and. 24, which screw-and-nut mechanism is operated by a hand-control wheel 26; A fine adjustment for movement of the roller 2 as a whole towards or away from the roller may be effected by the rotation of the cross shaft 25 and eccentric by means of a screw-and-nut device 34 which forms a connection between the operating lever l5 and a lever arm fixed to the cross shaft. The operating lever l5, in addition to controlling the distance apart of the rollers 2 and 3, operates a clutch associated with feeding mechanism. The

operating lever i5 has a boss 38 provided with a hole39 having its axes parallel but displaced from, the axis of the cross-shaft, which hole is engaged by a pin 30 at the end of the link 4|. lI'he other end of the link is adjustably connected to a tie member 42 which is slotted at both ends at 43. Two studs 44 extend through the slots and engage respectively the link 4| and a rod 45; The rod extends through a slot 46 in a lever arm 47. The rod is encircled by a. compression a washer 50 which engages the end of the lever arm 41. The rod is engaged on the opposite side of the lever arm to the washer 50 by nuts 5| and a washer 52 which is disposed between a nut and lever arm. The lever arm 4'! is attached at one end of a short stub shaft 53 which is rotatably mounted in a bearing member 54 attached to a gear casing 55. Projecting from the inner end of the stud shaft is a pin 56 which engages a circumferential slot 57 formed in a clutch member 58 rotatably mounted on a driving shaft 59, whereby the clutch member may be 'moved axially along the shaft into and out of engagement with another clutch member 60 "fixed to the driving shaft 59 driven by'the electric'motor 9a driving the grinding rollers 2 and 3 by suitable belt and pulley drive 66 and 61 shown in Figure 2,but omitted from Figure 1 for convenience. The first-clutch member 58 is fixed to a pinion 6| which is arranged to engage two spur-wheels 62 and 63 arranged on either side of it. These two'spur-whe-els are fixed to the shafts E i-and 55, respectivelyyof the two feed rollers 3i and 32. I V

The operating lever [5 also controls an electric switch I! (see Figure 2) in circuits with the driving motor 9a. For this purpose the lever is provided.- with' a cam l6 which is arrangedto come into contact with a spring-controlled switch-arm 33 when the rollers have been separated. For this purpose thelever arm is provided at a controlled rate by the feed rollers 3| and 32 which drive through suitable gearing from the .-motors 9a. Thus the feed of materialwill be stopped when the circuitof the motor is broken upon separation of the rollers and started again when the rollers are'brought together. The cirshown in Figure 2. 7

cuit connections of the switch and motor are spring 48 which at the oneend abuts a shoulder I 59 on the rod and at the other abuts against As will be seen from Figure 2, the cross shaft 25, on which the operating lever I is mounted, is ar-' ranged within the main casing of the machine and the lever arm extends out through a slot formed between the parts 21 and 28 of said main casing. In order to prevent dust and dirt entering the machine through this slot, the lever arm has attached thereto two shields 29 and 30 which between them serve to obscure the slot for any position of the lever I5.

I claim:-

1. A milling machine comprising two milling rollers, a fixed mounting for one roller, a movable mounting for the other roller, hand-controlled means associated with the movable mounting for adjusting the distance apart of the rollers, gearing between said rollers which permits movement of the movable roller without disengagement of the gearing, means for feeding the material to be ground to the rollers, an electric motor adapted to drive both one of the members of the gearing and said feeding means, an electric switch in circuit with said motor and so operatively connected to the hand-controlled means that the circuit is closed when the rollers are brought together and opened when the rollers are moved apart.

2. A milling machine comprising two milling rollers, a fixed mounting for one roller, a movable mounting for the other roller, a gear-wheel fixed to each roller, a train of intermediate pinions connecting said gear-wheels, means for so constraining the movement of the movable mounting that the common tangent of the pitch circles of the gear-wheel on the movable roller and the pinion with which it engages is substantially parallel with the initial direction of movement of the roller, upper and lower casing parts, the lower of which parts supports said intermediate pinions and constitutes an oil well, an electric motor mounted on said lower casing part and connected to one of said pinions, which lower casing part is pivotally mounted so that the pinions may be withdrawn from engagement with the gear-wheels to an extent which permits axial removal of the rollers and means for locating the lower casing part in an open position so as to retain the oil therein. I

3. A milling machine comprising two milling rollers, a fixed mounting for one roller, a movable mounting for the other roller, hand-controlled means associated with the movable mounting for adjusting the distance apart of the rollers, gearing between said rollers which permits movement of the movable roller without disengagement of the gearing, means for feeding the material to be ground to the rollers, an electric motor adapted to drive both one of the members of the gearing and said feeding means, an electric switch in circuit with said motor and so operatively connected to the hand-controlled means that the circuit is closed when the rollers are brought together and opened when the rollers are moved apart, and means for closing the switch at the commencement of the movement of the rollers together and to open it when the rollers are moved almost to their full extent apart.

4. A milling machine comprising two milling rollers, a fixed mounting for one roller, a movable mounting for the other roller, hand control means associated with the movable mounting for adjusting the distance apart of the rollers, a gearing between said rollers which permits movement of the movable roller without disengagement of the gearing, two feed rollers for feeding the material to be ground to the milling rollers, an electric motor adapted to drive one of the members of the gearing for the milling rollers and also to drive the feed rollers, a clutch between the motor and the feed rollers and operatively connected to said hand control means, an electric switch in circuit with said motor and also operatively connected to said hand control means whereby the clutch is arranged to be disengaged before the milling rollers are fully separated and before the electric switch is opened.

5. A milling machine comprising two milling rollers, a fixed mounting for one roller, a movable mounting for the other roller, hand control means associated with the movable mounting for adjusting the distance apart of the rollers, a casing surrounding said rollers and formed with a slot through which said hand control means extend, a shield attachedto the hand control means of such a size as to cover said slot-for all positions of the control means and so positioned as to form an efiective seal with said casing, gearing between said rollers arranged to remain in engagement during the movement of said movable roller, an electric motor for driving said gearing, an electric switch in circuit with said motor and means operated by said hand control means for closing said switch at the commencement of the movement of the rollers together and for opening it when the rollers are moved almost to their full extent apart.

AUGUSTE FREROTTE.

Images