US1915175A - Safety locking device - Google Patents

Description

June 20, 1933.

F. H. WRIGHT ETAL SAFETY LOCKING DEVICE Filed Nov. 8, 1929 5 Sheets-Sheet l June 20, 1933.

F. H. WRIGHT ET AL SAFETY LOCKING DEVICE 3 Sheets-Sheet 2 Filed Nov. 8, 1929 June 20, 1933. F. H. WRIGHT ET AL 1,915,175

SAFETY LOCKING DEVICE Filed Nov. 8, 1929 s Sheets-She et s Q i er/707's HJVMy/Ff; .7141. 84/: 1S

' iffy v Patented June 20, 1933 UNITED STATES trans- PATENT? or FREDERICK nun-sir WRIGHT, on LONDON, AND EDMUND WoonwAnDzLnwIs, or

LEISTON, ENGLAND, AssIGNoB-s TO THE CENTURY MACHINE COMPANY, on em- CINNATI, OI-I IO SAFETY LOCKING DEVICE Application filed November 8, 1929, Serial No. 405,819, and in Great Britain January 16, 1929.

This invention relates to machines for mincing meat, and is an improvement in or modification of the safety devices described ,7 in United States Patent #1,782,084e, dated November 18, 1930.

The objects of the present invention are firstly,-to improve the safety catch locking the cover to the knife bowl in such a manner thatthe working parts are enclosed as much 7 w aspossible; secondly, to simplify the safety locking of the handles controlling the clutch on the knife spindle and the motor switch; thirdly, to employ amechanical governor control instead of an electro-magnetic control to retain the coverclosed until the moving parts have lost their momentum and are at rest; and fourthly, a simplification of the clutch driving the bowl V According to this invention, the opening and closing movement of the cover of the knife bowl causes the lug or pin thereof to engage in an open slot of a cam piece secured on the outer end of a short shaft which projects through a casing enclosing the sliding bolt or catch. On the inner end of this shaft is fixed a boss with oppositely disposed stops or projections, one of which is either in the pathof a lug on theend of the sliding bolt, or is turned down to permit the bolt to slide, and the bolt in its new position holds the stop down; the other stop is engaged by a flat blade spring. 3

The trip leversof the prior specification are replaced by a single lever pivoted at or 5 near its centre about midway between the two hand levers controlling the clutch mechanism and motor switch respectively, and the spindle of each hand lever is provided with a grooved or notched disc which co-acts with the corresponding end of the pivoted lever.

By this device, the switch must first be turned o off before the clutch can be disconnected and the cover opened, and the switch is then automatically locked so long as the cover remains open.

The governor control which replaces the electro-magnetic rheostat is mounted on the vertical shaft which is directly geared to the motorshaft, and a slidingcollar on the governor shaft is pushed by the governor against a hanging catchpiece and holds it in the path ofa promotion fixed on the clutch link mechanism, thereby locking suchmechanism until the speed of the governor falls, sufiiciently to lower the collar and release the hanging catchpiece.

The shaft driving the bowl is operated through a. clutch independently controlled by a separate handle, and is not directly subject to the controls described above; I

- The invention is illustrated in the accompanying drawings in which Figure l is an elevation of the machine partly in section and with part of the lower cover removed to show the safety locking control, the switch being off and the clutches 1n neutral position. a r Y T 5 Figure 2 is an end elevation of the machine with the end cover removed.

Figure 3 shows the safety locking control when the mincer only is, working.

Figure at shows the cam and boss which are operated by the hinged cover of the knife bowl, the parts being in the position in which the sliding bolt is locked and the cover is open.

Figure 5 shows the same parts as in Figure 4: but turned through a right angle by the descent of the cover, leaving the'sliding bolt clear of its stop.

Figure 6 is a plan view of the device shown in Figure 1.

The machine, as in the prior specification comprises a main framing A which carries a mincer B, cutter C, and motor D. The clutch E on the motorshaft drives the spindle F of the cutter knives G, and the mincer B is driven from the motor D by worm gearing H, I, vertical shaftJ, clutch K, and worm gearing M.

The first improvement under the present invention relates as described above to .the locking of the cover a of the knife bowl, which cover is swingingly supported on a pipe 79. For this purpose there is provided a short shaft 1 which projects through the casing 2 enclosing the sliding bolt or catch cl, and to the outer end of the shaft 1 is fixed a cam piece 3 having an open slot 4 as shown in Figures 4 and 5, this slot being in the path of a lug 0r pin a on the cover a. The lug or pin a conveniently is in the form of a bar which is fixed to an upstanding flange a by means of bolts of so as to lie in the path of the cam piece 3. On the inner end of the shaft 1 is fixed a boss 5 provided with stops on projections 6, 7. The stop 6, in the position shown in Figure 4; is interposed in the path of .the rearwardy-turned end d of the sliding bolt 03, the cover a being partly or wholly raised; the bolt d with its operating linkage 0 k is thus locked, and the stop d fixed to the bolt, holds the clutch E out of engagement. At the same time the boss 5 is held'firmly by the spring 8 engaging the projection 7. When the cover is closed, the projection a turns thecam 3,

and the boss .5 assumes the position shown inFigure 5, carrying the stop 6 downwards outof the path of the rearwardIy-turned end (P of the bolt, and the projection 7 is again held firmly in its new position bythe spring 8. The bolt may now be shifted by the handle g to bring the clutch E into engagement,

and the end d of the bolt now prevents the stop 6 from turning back.

The hand lever 9 can be turned to start either the mincer or the cutter; in the po si-' tion of the lever 9 shown in full lines n Fig ure 3, the mincer clutch K is brought lIltO' operation, and in the diametrically opposite position of the lever g the cutter clutch E is brought into operation.

By this device the cover cannot be opened until the clutch E has been disconnected, and the clutch cannot be again connected until the cover has been closed.

The second improvement of the present invention relates to the safety locking of the hand levers 9, 12, the latterbeing the motor switch handle. Referring to Figure 3, both ends of the trip lever u are formed as-projections u, u which tend to enter grooves or notches in theedges of circular disc '0 9 secured to the spindles of the handles 1), g. The disc g has two opposite grooves or notches 9 g, one or the other of which is engaged by the projection a when the corresponding clutch is in gear. The disc 12 hasa single groove or notch '0 and a projection v. When the switch is on as shown in Figure 3, the projection '12 engages in a groove 10 on the trip lever u and tilts the lever so that the end 14 engages in the notch 9 the handle 9 cannot then be turneduntil the switch handle 0 is turned over to its off po-' sition shown in dotted lines, thus bringing the groove v over to allow the end a to enter and free the lever u. Thehandle 9 may now be turned to the neutral position shown in the dotted lines in Figures 1 and 3, thus bringing the circular edge of the disc 9 to bear on the end u" as shown in Figure 1 and looking the switch handle 0 in its offposition. The disc 9 carries a roller 2' which engages in an open slot k of the link is; the link is and sliding bolt d are therefore locked whenever the handle 9 is locked, even if the bolt d is free from the stop 6.

The third improvement, namely the mechanical governor control to lock the clutchoperating linkage after the switch has been turned ofi and until the revolving parts have lost their momentum, is shown in Figure 2 and consists of a centrifugal governor 9 mounted on the shaft J, a collar 10 sliding has been turned off and the speed of theshaft J is reduced, the collar 10 is lowered to free the catchpiece 11 from the projection 12. The handle 9 may then be actuated to disconnect the clutch; if this is the cutter clutch E, the cover a can then be opened.

The fourth improvement relates to the driving of the knife bowl C. In the prior specification, a clutch was provided at the lower endof the shaft J to drive the shaft Q- and worm wheel P secured to the spindle of; the bowl. By the present improvement the shaft 0 is driven provided with a clutch'13 which is operated by a separate handle 14 and is'driven from the worm N on the shaft J. The clutch 13 is independent of the controls described above.

What we claim is I 1. A safety locking device for meat mincing machines of the type including knives, an operating shaft for'the knivesincluding a clutch and'a cover for the knives, said safety locking deviceincluding a sliding bolt controlling the clutch, a stop cooperating with the bolt and movable to either of two positions, said stop in-the first position serving to maintain the bolt fixed against operative movement in a position to hold the clutch disengaged,'said stop in a second position permitting movement of'the bolt in a direction and to an extent to permit the clutch to engage, and cooperating means carried by the cover and stop to operate the stop in the movement of the cover, said cooperating means in the opening movement of the cover serving to move the stop to the first position, said cooperating means in the closing movement of the cover serving to move the stop to the second position. V

2. A safety locking device as defined in claim-1, including a spring cooperating with the stop to hold it against casual movement in either the first or second position.

3. A safety locking device as in claim 1, lncluding a governor operating a sliding col- 1211' serving to hold a hanging catch piece in the path of a projection on the clutch link mechanism.

In Witness whereof We have hereunto signed our names.

FREDERICK HUB-SH WRIGHT. EDMUND WOODWARD LEWIS.

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