RU2440653C1 - Pruning shears with automatic drive - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: pruning shears with two handles (1), held by a cutter operator's hand (5), comprises an additional lever (2), combined with one of its handles. A traction Bowden wire (3) is connected to this lever, and its shell is fixed to the second handle of the pruning shears. The other end and the shell of the Bowden wire are connected to a power mechanism of a drive (4), which may be arranged on the body of the cutter operator (5) or on a mobile chassis (6). The device to start a mechanism of a drive (7) by a signal of a cutting force sensor (8), arranged on the pruning shears, puts the power mechanism of the drive (4) in operation, which pulls the wire (3), attached to an additional lever of the pruning shears handle (2), and cuts a fruit tree branch. The force sensor transfers a signal proportional to the cutting resistance force, and at a certain threshold value it automatically connects the mechanical drive from an additional source of power supply. At lower values of the sensor signals, cutting is done manually, which makes it possible to save energy of mechanical drive supply source at low cutting forces.

EFFECT: increased convenience and efficiency in operation of pruning shears.

1 dwg

Description

The invention relates to agricultural machinery and is intended for trimming the branches of plants, fruit trees and berry bushes in a semi-mechanized way.

There are various designs of secateurs that work only from the efforts of the muscles of the trimmer operator. Signs similar to the claimed device are articulated cutting elements combined with levers-handles and with or without intermediate mechanical transmissions. Manual secateurs are widespread due to the simplicity of design, low weight and ease of handling. Despite this, they have a serious drawback associated with muscle fatigue, and, as a consequence of this, the low productivity of the trimmer operator per shift.

Various designs of mechanized cutting tools with electric, hydraulic and pneumatic drives are also known. For example, a pneumatic pruner according to A.S. No. 182431 (publ. May 25, 1966, BI No. 11), comprising a housing with a pistol grip with an air distribution device, a power cylinder attached to the housing, a return spring and a rod connected to a working body such as scissors, characterized in that, in order to increase the cutting force, the power cylinder is made paired, with two pistons. A sign similar to the claimed device, the use of the conversion of external energy into mechanical energy to drive the cutting elements held by the hands of the operator-trimmer. A disadvantage of the known device is that the entire mechanism for cutting secateurs cutting elements must be held by the trimmer operator by hand, which is a certain inconvenience in the work and ultimately affects the productivity of the operator.

Closest to the claimed invention is a foot pruner for A. with. No. 663351 (published on May 25, 1979, BI No. 19), comprising cutting and counter blades with levers connected to a drive mechanism including a pressure plate and a support plate, characterized in that, in order to expand the pruning range of the secateurs, the drive mechanism is equipped with a cable with a Bowden sheath, one end of which is connected to the pressure plate and the other to the lever of the cutting blade, with one end of the Bowden sheath mounted on the lever of the opposing blade, and the other on the base plate. The known device contains the following features, coinciding with the features of the claimed device: cutting and antiskid blades with levers connected to the drive mechanism using a cable with a Bowden sheath. In general, the design of the known foot pruner is fundamentally different from the claimed one and has a number of disadvantages. Firstly, the cutting blades are driven by the muscles of the legs of the trimmer operator. This causes fatigue and a decrease in productivity per shift. Secondly, the cutting elements do not have the ability to be activated by the efforts of the muscles of the hands of the trimmer operator, for example, when cutting thin branches. The well-known foot pruner is also inconvenient in operation, since the drive mechanism located on one of the operator’s legs will constantly tire with its weight and prevent it from occupying a comfortable body position. Thus, the known design is inconvenient in operation and unproductive.

The proposed device, shown in the drawing, includes a secateurs with two handles (1) having an additional lever (2) combined with one of its handles. The Bowden traction cable (3) is attached to this lever, and the cable sheath is fixed to the second secateurs handle. The other end of the cable is connected to the power drive mechanism (4), which can be located on the torso of the trimmer operator (5) or on the mobile chassis (6). The device for starting the drive mechanism (7) is triggered by the signal of the cutting force sensor (8), which is located on the pruner.

During the pruning process, the pruning operator brings the pruner to the branch of the plant and squeezes its arms. In this case, the signal of the cutting force sensor (8) is compared by the trigger device of the drive mechanism (7) with the set threshold value of operation. If the cutting force is lower than the set response threshold, then the cutting continues due to the efforts of the muscles of the hands of the trimmer operator, otherwise the drive mechanism (4) starts automatically, which pulls through the Bowden cable (3) an additional lever of the secateurs handle (2) and cuts branches using an additional source of energy.

The claimed invention solves the following technical problems:

1. Improving the design of the secateurs, which allows the use of two sources of energy, depending on the required cutting effort — the energy of the muscles of the hands of the trimmer operator and additional energy through the drive mechanism, thereby reducing the operator’s labor costs when cutting thick branches and increasing the efficiency of mechanical drive due to the exclusion of small loads and idling during manual cutting.

2. Improvement of the method of secateurs drive, which allows to reduce the weight of a part of the tool held by the hand of the trimmer operator, and transfer the rest of the weight to the torso of the trimmer operator or a separate mobile chassis, thereby improving the convenience of using hand tools and increasing labor productivity.

The tasks are solved by the manifestation of several technical effects of the claimed device secateurs:

1. Combining the handle with the lever allows cutting from two sources of energy - from the efforts of the hands of the operator-trimmer and from the efforts of the drive mechanism, powered by an additional energy source.

2. Using a cutting force sensor and a device to start the drive mechanism allows you to turn on the drive automatically, depending on the set limit of the cutting force manually.

3. Using the Bowden cable to transfer energy from the drive mechanism to the secateurs allows you to transfer most of the mass of the tool from the hands of the trimmer operator to the torso (for example, to the belt, back or shoulders) or to a separate mobile chassis.

Claims (1)

A device comprising a manual secateurs, a Bowden traction cable, a drive mechanism, a secateurs cutting force sensor and a device for starting a drive, characterized in that a lever is connected to one of the secateurs handles, to which one end of the traction cable is attached, and the cable sheath is attached to the other handle secateurs; the other end of the cable and the cable sheath are connected to the power mechanism of the drive, located on the torso of the trimmer operator or on the mobile chassis, and switched on automatically using the drive start device, which determines the start time compared to the set threshold value with the value of the cutting force of the pruning shears measured by the sensor effort, which is placed on the pruner.