Hedge trimmer

• US 4,619,045 A
• Filed: 03/29/1985
• Issued: 10/28/1986
• Est. Priority Date: 06/26/1984
• Status: Expired due to Term

• Current Assignee: Andreas Stihl 7050 Waiblinger Germany
• Original Assignee: Andreas Stihl
• Inventors: Mayer, Gunter
• Primary Examiner(s): Peters, Jimmy C.
• Application Number:
  US06/717,459
• Time in Patent Office: 578 Days
• Field of Search: 30/210, 30/215, 30/216, 30/217, 30/200, 30/382, 30/209, 30/213, 30/214, 30/221, 30/222, 30/223, 30/224
• US Class Current: 30/216
• CPC Class Codes: A01G 3/053 motor-driven

Abstract

The invention is directed to a hedge trimmer having a pair of elongated cutters journalled for reciprocal movement. The two movable cutters are journalled on a guide bar so as to be movable in the longitudinal direction thereof and include cutting teeth which extend transversely to the direction of movement. Protective teeth are arranged with respect to the guide bar and are arranged next to the cutting teeth so as to be parallel thereto. The protective teeth are configured to be so long that the free end portions thereof project outwardly beyond the outer edges of the cutting teeth.

Claims

1. A hedge trimmer comprising:

a housing;

a guide bar having two flat sides and being mounted on said housing, the guide bar defining a longitudinal axis;

a pair of elongated flat cutters journalled for reciprocal movement on one of the flat sides of said guide bar so as to cause one of said cutters to be sandwiched between said one flat side and the other one of said cutters;

reciprocating drive means for reciprocating said cutters in mutually opposing movement along said axis;

each of said cutters having a plurality of cutting teeth projecting laterally of said axis;

an elongated cover mounted on said guide bar and being formed to define a substantially U-shaped channel having an elongated recess for accommodating said guide bar therein;

said cover having a plurality of protective teeth projecting laterally and outwardly from the legs of said channel so as to be parallel and adjacent to said cutting teeth;

said protective teeth having respective end portions overlapping and projecting outwardly beyond said cutting teeth; and

,

said channel having a depth corresponding substantially to the thickness of said guide bar so as to cause said one flat side to be flush with said protective teeth and to place said one cutter directly next to said protective teeth thereby defining a very narrow glide cap between said one cutter and said protective teeth so that practically no sliding friction can occur therebetween.

2. The hedge trimmer of claim 1, the spacing in the direction of said axis between adjacent ones of said protective teeth being substantially the same as the spacing in the direction of said axis between adjacent ones of said cutter teeth.

3. The hedge trimmer of claim 2, the width in the direction of said axis of said protective teeth being substantially the same as the width of said cutter teeth.

4. The hedge trimmer of claim 1, said end portions extending outwardly beyond the outer tips of said cutter teeth by an amount corresponding to 1/4 to 1/2 of the length of said cutting teeth.

5. The hedge trimmer of claim 1, said cutting teeth having a trapezoidal configuration and said protective teeth having a trapezoidal configuration substantially the same as said cutting teeth.

6. The hedge trimmer of claim 1, said elongated metal cover and said protective teeth being made of the same material and configured as a single integral piece.

7. The hedge trimmer of claim 1, said cover being made of metal and further comprising reinforcement rib means for reinforcing said protective teeth.

8. The hedge trimmer of claim 7, said rib means being a plurality of ribs for reinforcing corresponding ones of said protective teeth, each of said ribs being configured so as to extend upwardly from the outer end of the protective tooth to the leg of said U-shaped channel from which said protective tooth laterally projects.

9. A hedge trimmer comprising:

a housing;

guide bar means mounted on said housing and defining a longitudinal axis;

a pair of elongated cutters journalled for reciprocal movement on said guide bar means;

reciprocating drive means for reciprocating said cutters in mutually opposing movement along said axis;

each of said cutters having a plurality of cutting teeth projecting laterally of said axis;

said guide bar means including a plurality of protective teeth projecting laterally of said axis and arranged so as to be parallel and adjacent to said cutting teeth; and

,

said protective teeth having respective end portions overlapping and projecting outwardly beyond said cutting teeth;

a first number of said plurality of protective teeth being arranged in a first row along said axis so as to be directed outwardly therefrom to the lefthand side thereof and the remainder of said plurality of protective teeth being arranged in a second row along said axis so as to be directed outwardly therefrom to the righthand side thereof, the protective teeth of said first row being displaced from the protective teeth of said second row by an amount equal to one-half of the spacing between adjacent ones of said cutter teeth.

10. The hedge trimmer of claim 9, said end portions of said protective teeth having respective rounded edges.

11. The hedge trimmer of claim 9, said guide bar means comprising a guide bar mounted on said housing, said cutters being journalled for reciprocal movement on said guide bar, said guide bar and said protective teeth being configured as a single piece.

12. A hedge trimmer comprising:

a housing;

guide bar means mounted on said housing and defining a longitudinal axis;

a pair of elongated cutters journalled for reciprocal movement on said guide bar means;

reciprocating drive means for reciprocating said cutters in mutually opposing movement along said axis;

each of said cutters having a plurality of cutting teeth projecting laterally of said axis;

said guide bar means including a plurality of protective teeth projecting laterally of said axis and arranged so as to be parallel and adjacent to said cutting teeth; and

,

said protective teeth having respective end portions overlapping and projecting outwardly beyond said cutting teeth;

said guide bar means including a guide bar mounted on said housing; and

, a cover bar mounted on said guide bar, said protective teeth being arranged on said cover bar, said cover bar and said protective teeth being made of the same material and configured as a single integral piece;

said cover bar having an elongated base extending in the direction of said axis and said protective teeth extending laterally from said base, said guide bar having an elongated side surface likewise extending in the direction of said axis; and

, said guide bar means further comprising fastener means for fixedly mounting said cover bar to said guide bar at said side surface.

13. The hedge trimmer of claim 12, said elongated base having an approximately U-shaped cross section defining an elongated recess for accommodating said guide bar therein.

14. The hedge trimmer of claim 12, said cutters being reciprocally journalled to said guide bar one atop the other so as to cause the outer surface of the cutter teeth of one of said cutters to be directly and tightly next to the inner surface of said protective teeth.

15. The hedge trimmer of claim 13, said cutters being reciprocally journalled to said guide bar one atop the other so as to cause the outer surface of the cutter teeth of one of the cutters to be adjacent the inner surface of said protective teeth, said guide bar means comprising a thin metal spacer disposed between said one cutter and said cover bar so as to define a narrow glide gap between the outer surface of the cutter teeth of said one cutter and the inner surface of said protective teeth.

16. The hedge trimmer of claim 12, said cover bar comprising said base and said protective teeth being configured as a sheet metal stamping.

17. The hedge trimmer of claim 16, said stamping being made of aluminum.

18. The hedge trimmer of claim 16, said cover bar further comprising reinforcement rib means for reinforcing said protective teeth.

19. The hedge trimmer of claim 18, said rib means being a plurality of ribs for reinforcing corresponding ones of said protective teeth, each of said ribs being arcuately configured upwardly from the outer side of the protective tooth and extending from said base to the end portion of the protective tooth.

20. A hedge trimmer comprising:

a housing;

a flat guide bar mounted on said housing and defining a longitudinal axis;

a pair of elongated flat cutters journalled for reciprocal movement on one of the flat sides of said guide bar;

reciprocating drive means for reciprocating said cutters in mutually opposing movement along said axis;

each of said cutters having a plurality of cutting teeth projecting laterally of said axis;

an elongated sheet metal cover configured as a metal stamping mounted on said guide bar and being formed to define a substantially U-shaped channel having an elongated recess for accommodating said guide bar therein;

said sheet metal cover having a plurality of protective teeth projecting laterally and outwardly from the legs of said channel so as to be parallel and adjacent to said cutting teeth; and

,

said protective teeth having respective end portions overlapping and projecting outwardly beyond said cutting teeth.