US 3182917 A
Description (OCR text may contain errors)
y 11, 1965 s. TAMNY ETAL BRUSH CHIPPER SAFETY CONTROL 3 Sheets-Sheet 1 Filed March 25, 1963 5/440 EMA/Y Dozwv B. [5124mm /Az f May 11, 1965 s. TAMNY ETAL 3,132,917
BRUSH CHIPPER SAFETY CONTROL Filed March 25, 1963 3 Sheets-Sheet 2 S/MQ/v ZbM/VY .Domv B. FZ/QLONG May 11, 1965 S. TAMNY ETAL BRUSH CHIPPER SAFETY CONTROL Filed March 25 1963 3 Sheets-Sheet 3 INVENTORS' S/MON ZZMA/Y DOA/N .B. UQLONG p/Az aw United States Patent 3,182,917 BRUSH CHIIPPER SAFETY CONTROL Simon Tamny, Los Angeles, and Donn B. Furlong, Claremont, Califi, assignors to Wayne Manufacturing Company, Pomona, Calif, a corporation of California Filed Mar. 25, 1963, Ser. No. 267,653 9 Claims. ([31. 241--36) This invention relates generally to brush or other wood chipping machines, and is directed particularly to improvements in safety controls for-hand fed machines in that category.
In the operation of a brush chipper having rotating chipping or cutting means and a feed chute, the operator normally stands at the mouth of the chute and feeds the brush to a chipping rotor to be cut into small pieces. The rotor may exert a strong pull on the brush placed in the chute and if the operator were to become entangled with the brush, he could be drawn into and injured by contact with the rotor.
This danger has been recognized in the past, and it has been proposed to supply brush chippers with safety control devices which de-energize the engine driving the rotor and apply a brake thereto. Some safety control devices utilize engine-derived energy stored in fluid under pressure to create the force necessary to de-energize the engine and apply the brake, e.g. Patent No. 2,880,942 to L. J. Hall. Utilizing fluid under pressure in this manner has the disadvantage of requiring a pump connected to the chipping rotor drive engine, and therefore in being subject to proper functioning and pressure maintenance by the engine operation. There is also a disadvantage in that the fluid could be lost by leakage from the fittings or ruptures in the fluid lines.
This invention seeks to avoid the drawbacks inherent in a pressurized fluid device by utilizing mechanically stored energy createdv and made available independently of the engine operation. For this purpose the invention contemplates the use of one or more springs and asso ciated mechanisms adapted to receive energy by being manually stressed to what may be termed cocked condition, from which the energy is instantly releasable for stoppage of the engineand chipper rotor,
Specifically, the invention contemplates a system of levers and coil springs which can be placed in an unstable or cooked condition wherein the springs are stressed, and which under the influence of a slight actuating force by the operator, will immediately return to the stable or uncooked position. The energy released by the springs in returning to the stable position creates the force necessary to de-energize the rotor engine and set the brake. After the rotor has been so stopped, the mechanical actuating system may then be recocked by the operator and normal operation resumed. 1
It is also an object of this invention to provide for a lever or equivalent means by which the operator triggers the actuator system, at a position so related to the mouth of the feed chute that the lever can be displaced by the operators legs or body if his arms became entangled in the brush being drawn towards the rotor.
These and other objects of the invention will be more fully understood from the following detailed description of a preferred embodiment of the invention as shown by the accompanying drawings in which:
FIG. 1 is a side elevation of the apparatus;
FIG. 2 is a fragmentary plan view as taken from line 2--2 of FIG. 1;
FIG. 3 is a fragmentary enlarged side elevation of the safety control device actuating means taken from line 3-3 of FIG. 2;
FIGS. 4 and 5 are enlarged fragmentary sections taken on lines 44 and 55 of FIG. '2;
3,182,917 Patented May 11, 1965 FIG. 6 is an enlarged showing of the safety control device with the levers in the unstable or cocked position;
FIG. 7 is a similar view showing the levers in the stable or actuated position; and 1 FIGS. 8 and 9 are sections taken respectively on lines 8-8 and 9-9 of FIG. 7.
The invention is shown to be embodied in a chipper machine shown typically to comprise a frame 10 suitably carried by wheels 11 and mounting an engine within the vented housing appearing at 12. Forwardly of the engine the frame mounts a chipper rotor '13 which as will be understood without necessity for further description, may be made in a customary manner to carry cutters operable to comminute brush or the like into chips whichare removed from the chamber within the rotor housing 14 by way of duct 15 having a hooded or baflled outlet at 16. The engine shaft 17 drives rotor 13 by way of belt 18 carried by pulleys '19 and '20 respectively on shaft 17 and the rotor shaft 21.
The brush to be comminuted is fed against the rotor by way of an open top chute generally indicated at 22 in the form of a base plate 23 having upstanding sides 24- which merge to an adaptor hood 26 which in turn converges to the rotor housing .14 so that the brush being fed from the chute is guided into contact with the rotor 13. The invention is occasioned by possible entanglement of an operator standing at the end of the chute 22 in brush being strongly pulled by the rotating action of the chipper, and as'previously indicated, the invention contemplates a form and arrangement of safety control devices which are actuable by the operator under circumstances when one or both arms are engaged or entangled in the feed.
For this purpose we provide an engine cutout and brake applying mechanism generally indicated at 27, the details of which are later described, responsive toactuation by [flexible connectors such as cable 28 running through a tubular sheath 29 and terminally engaged beyond the sheath-supporting bracket 30, see FIG. 5, with a cross bar 31 extending transversely beneath the chute '22.. The cable is shown to have a terminal connector .32 extending through opening 83 in the bar to an enlarged swivel bearing 34. The bar 31 is shown to be mounted for swinging movement on a pair of arms 35 having intermediate pivotal attachments at 36 to the sides 24 of the chute. The upper ends of the arms 35 may carry plates 37 available at the sides of the chute to be pressed by the operator to swing bar 31 from its stop 38 and pull the cable 28 to trigger the mechanism 27, as will appear.
Such cable displacement and triggering action may also result from the operation of a supplemental safety actuator generally indicated at 39 and comprising a pair tors legs, thus affording a control independent of hand to a link 4-5 which is terminally connected at 46 to bar 31. The upper terminal of the second arm 40 attaches to coil spring 47 which normally maintains the bar or rod 43 in the solid line position illustrated, as determined by the engagement of bar 3 1 against stop 38. As will be apparent, displacement of member 43 to the broken line position 43a of FIG. 3 by leg pressure from the operator, will displace cable 28 by the bar movement resulting from swinging of arms 35.
Referring now to FIGS. 6 through 9, cable 28 eXtend ing to the mechanism 27 is engaged therein at 49 with a lever 56, 50a pivoted at 5:1 to a bracket 52 affixed to the housing 53. Displacement of connector 28 in the direction of arrow 54 (FIG. 6) causes the lever assembly 50, 50a to rotate counterclockwise about the pivot 51 against the resistance of spring 55 from a rest position determined by the engagement of adjustable screw 56 against stop 57. The lever arm 50a is pivotally connected at 58 with a link 59 which attaches pivotally at 60 to arm 61 pivotally mounted at 6-2 to bracket 63, see FIG. 7. The arm 61 terminally carries a cross piece 64 which is engaged at 65, see FIG. 8, by the terminals of coil springs 66 at opposite sides of the arm and affixed at their ends 67 to the housing 53.
A switch 68 mounted on bracket 69 is connected in the engine coil circuit 70, and is positioned to be actuable by engagement at 71 with the arm 61 to close the switch for normal running of the engine.
The control mechanism 27 also includes a master hydraulic cylinder 71 having its piston rod 72 pivotally connected at 73 to the arm 61. Line 74 transmits hydraulic fluid pressure from the master cylinder '71 to a brake assembly generally indicated at 85, see FIG. 2, which may be of any conventional design operable in response to the transmitted hydraulic pressure to stop the chipping rotor shaft 17. Without undertaking unnecessary detail, the brake assembly 85 is shown to comprise a drum 86 attached to the rotor shaft, and a brake shoe arrangement 87 operable in the usual manner by conventional means diagrammatically indicated at 88 to arrest the drum and shaft rotation as hydraulic pressure is transmitted through line 84.
The springs 66 are stressed and the lever system brought to its FIG. 6 condition by upward swinging of a hand lever 90 having its inner turned end mounted at 91 for rotation in bracket 92, the lever having a fixed arm 93 pivoted at 94 to a pair of links 95 slideable on support 96 welded to arm 61 and receiving between them the arm 61 to the right of pin 97 bridging the links. Upward swinging of arm 90 from the FIG. 7 to the FIG. 6 posi tion brings pin 97 into engagement with arm 61, swinging the latter to swing the arm 50a and link 59 to the undercenter condition of FIG. 6. Thus the arm 50a and link 59 constitute a toggle capable of undercenter throw as determined by the adjustment of screw 56 to releasab-ly retain the lever system cocked with the springs 66 constantly tensioned.
In considering the operation of the mechanism, assume actuation by the machine operator of either of arms 35 or bar 43 to transmit pull to the cable 23. The latter through its connection at 49 with the toggle arm assembly triggers release of the toggle, freeing the springs 66 for contraction and resultant movement of arm 61 away from contact with switch 68, thereby opening the engine coil circuit and stopping the engine. Simultaneously arm 61 shifts the hydraulic cylinder piston rod 72 to apply and transmit hydraulic fluid pressure through line 84 to the brake 85, causing the latter to immediately arrest turning of the rotor 13. During this control actuating sequence, lever 90 becomes free to drop to the lower position of FIG. 6, from which it may be manually returned to the elevated reset position to again restore the mechanism to cocked position, as previously explained.
1. In combination with a wood chipping machine comprising a chipping rotor, an engine for driving the rotor,
4 said engine having an electrical coil circuit, and a chute positioned for manual feeding therethrough of brush or the like to the rotor, safety control mechanism comprising (A) cutout means in said coil circuit operable to deenergize the engine,
(B) a brake system operable to arrest rotation of said rotor,
(C) spring means,
(D) means for manually stressing said spring means,
(E) means for releasably retaining said spring means in stressed condition,
(F) means for manually actuating said retaining means to release the spring means from stressed condition, and
(G) means for transmitting the energy of the spring release to said cutout means to de-energize the engine and to said brake system to stop the engine and rotor.
2. The combination of claim 1, in which said retaining means (E) comprises a lever system connected to the spring means and operating in cocked condition to releasably retain the spring in stressed condition.
3. The combination of claim 2, in which said lever system includes a toggle operable in cocked position to retain the stressed condition of the spring means and from which position the toggle is actuable by said means (F) to release the spring energy.
4. The combination of claim 2, in which said stressing means (D) comprises a hand actuable lever operatively connected to the spring means.
5. The combination of claim 1, in which said cutout means (A) is a switch in the engine coil circuit.
6. The combination of claim 1, in which said brake system includes a hydraulically actuable brake and said central system operates to apply hydraulic pressure to the brake.
7. The combination of claim 1, in which said actuating means (F) comprises a member movably positioned at the mouth of the chute and actuable by an operator feeding into the chute.
8. The combination of claim 1, in which said chute is positioned to extend horizontally to the rotor, and in which said actuating means (F) comprises a member movably positioned at the underside of the chute mouth for actuation by the leg of an operator feeding into the chute.
9. The combination of claim 8, in which said actuating means (F) also includes manually operable means movably mounted at the side of the chute.
References Cited by the Examiner UNITED STATES PATENTS 2,559,701 7/51 Becker 241-222 2,766,417 10/5 6 Merritt. 2,880,942 4/59 Hall 241-222 FOREIGN PATENTS 261,627 9/ 49 Switzerland.
J. SPENCER OVERHOLSER, Primary Examiner.
WILLIAM W. DYER, 1a., Examiner.