DE3132478A1 - DEVICE FOR ADJUSTING THE CUTTING HEIGHT IN A HORIZONTAL MOWER OF THE HORIZONTAL TYPE - Google Patents

Description

Device for adjusting the cutting height at a horizontal type lawn mower

The present invention relates to a device for adjusting the cutting height in a horizontal type lawnmower in which the drive shaft protruding vertically downward from the engine from a spindle protruding from the motor and from a spindle surrounding the spindle., in the longitudinal direction the spindle is displaceable bush, the knife is attached to the lower end of the bush and

wherein between the spindle and the bushing the rotary. Movement-transmitting organs are provided for transmitting the rotational movement of the spindle to the bushing. Up to now, a device for adjusting the cutting height _{5 is known} which consists of one at the

■ there is a vertical disk attached to the wheels on the housing, the upper edge of which has holes or incisions. By "" The disc is rotatably mounted on the housing an angle lever, the substantially vertical leg of which has projections into the holes or incisions of the disc fit, and the axis of the wheel is mounted on the horizontal leg. By means of this device can 'The height of the housing and thus of the knife can be adjusted from the floor.

This solution has several disadvantages. If, for example, the housing is lifted to its greatest height, the gap remaining between the lower edge of the housing and the bottom surface exceeds that in many Countries prescribed maximum value. For this reason, similar lawnmowers often have to be on wheel axles, for example mounted side shields. ' The setting operation is also time consuming because of there is a separate adjustment device for each wheel, and because of the locking event of the adjustment lever the setting operation is also exhausting · ■ Besides it should be noted that the construction is proportionate

is weak because the wheel axles cannot be mounted directly on the housing, and that the realization of the Self-propelled in the power transmission device requires special solutions because the distance between the Motor and the "wheels when adjusting the cutting height is changeable.

In Swedish Patent Specification No. 3 ^ 7 419 a lawnmower is described, the drive shaft of which is surrounded by a bushing which extends along the shaft can move. As an organ that transmits the rotary movement • and adjusts the altitude, a is on the Radial pin attached to the inner surface of the bushing, which is in a 'provided on the surface of the shaft Can move the groove, which groove is located obliquely to the longitudinal direction of the .Welle. By means of this construction can the knife can be made to automatically produce two different ones Record high altitudes by changing the direction of rotation of the knife.

The purpose of the present invention is to create a device for adjusting the cutting height, with the help of which the height of the knife can be adjusted without changing the direction of rotation. the The invention is characterized in that there are resilient locking members between "the spindle and the bushing gives the detachable locking of the socket in the

desired position in the longitudinal direction of the spindle and that the outer surface of the socket is aligned with the circumference Has grooves into which grooves' -a projection of the setting lever penetrates the inevitable Moving the bushing from one position to the other along the spindle .. Thanks to this construction the ground clearance of the housing does not change, for which reason the side shields are omitted · Can be. The wheels can be fixed directly to the housing in a stable manner, and the adjustment measure can be used as a 'a quick movement performed with a single lever will. The difficult to perform switching of the rotation

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direction of the motor is also not required. Of the Lawn mowers can be lighter than before than self-propelled because the distance between the motor and the wheels is invariable, and so is the automation the cutting height adjustment is easier -. manageable.

The "device according to the invention will be described in more detail below with reference to the accompanying drawing ₃ wherein

FIG. 1 shows a favorable embodiment of the device according to the invention as a longitudinal section,

FIG. 2 shows a second embodiment of the device as a longitudinal section.

FIG. 3 the embodiment according to FIG. 2 .15 shows as a cross section along the line III ... III in Figure 2, -. ·

FIG. 4 shows, partly as a longitudinal section, a third embodiment of the device, Figures 5 and 6 represent two further embodiments of the spring of the locking member, and

Figure 7 shows a second embodiment of the displacement device the socket represents.

In Figures 1 to 3, the protruding from the engine of the lawnmower vertically downward Rotary spindle 1 and the blade 2 of the lawn mower are shown. According to the first two embodiments of the invention. the lower part of the spindle is surrounded by a sleeve 3, the inner surface of which has a longitudinal groove 4 has, penetrate into the two flat semicircular wedges 5, the curved end of which into the depressions the spindle penetrates. The action of the wedges causes the sleeve 3 to rotate together with the spindle. The sleeve is attached in the longitudinal direction to the spindle with a bolt 6.

The sleeve 3 is again surrounded by a bushing 7 which extends in the longitudinal direction in relation to the sleeve but the spindle can move with the

Sleeve 3 is locked in the circumferential direction by means of a wedge 10 laid in a longitudinally directed groove (FIG. 3) located in the outer surface of the sleeve and in a corresponding groove 9 (FIG. 3) located in the inner surface of the socket 7. According to the Figure 1, the inner surface of the bushing 7, for example, four recesses 11, into which the outside can penetrate 14 of the laid in the located on the outer side of the sleeve 3 "Umkreisnute 12 spring washer. 13 The spring ring is abgeschnittenj when wedge 10 and between the ends of the wedge 10 and the side surfaces of the wedge 10 have been left with a small amount of play ₃ so that the outside diameter of the spring ring can be smaller when the spring is displaced from one recess into the other Well 11 placed.

In the one shown in FIGS. 2 and 3 Embodiment, the bottom of the groove 9, for example, three depressions 11 into which the outside 14 of the in the incision 12 of the wedge 10 laid flat spring 13 can penetrate. In Figure 2, the protruding Central part 14 placed in the central recess 11.

On the periphery of the socket J a groove 15 runs - into which two rod-like arms 16 and 17 penetrate (Fig. 3) _3, the ends of which are located radially in relation to the spindle. The arms 16, 17 are _{attached to the lever 18 3} 19 which can be rotated to the left and to the right in FIG. 2, the ends of the arms 1.6 ₃ 17 forcing the bushing 7 into its lower or upper position. Because the knife 2 is attached to the lower end of the bushing 7, the cutting height can be adjusted with the lever 19. A vertical movement is only carried out by the bushing and the knife ₃ while the housing of the lawnmower remains at a constant height above the ground.

In the figure, K, a third embodiment of the apparatus is shown according to the invention.

_{The sleeve 3 5} is missing in it, with which a flat round wedge (so-called Woodruff wedge) in the recess of the spindle JL

and is located in the longitudinal groove 9 of the socket. On the bottom of the groove, there is an elongate arched flat spring 2I ₃ make three recesses 22 as viewed from the direction of the spindle which bulges, for example. By the action of the spring it sets. The bush 7 moves in the vertical direction So ₃ that the wedge 20 is located at any recess of the flat spring. If one wants to 'doubled such as "the cutting height, shifts to the socket 7 _s has been moved to the lowermost groove of the spring to the height of the wedge 16 by means of the Arm'e, 17 against the force' of the spring 21 upward.

In Figures 5 and 6, two alternative spring designs are shown. These feathers are stronger 1'5 than-the springs shown earlier.

In the figure 7 a second embodiment of the displacement device for the socket is shown. A ball bearing 23 surrounding the bushing is partially sunk in a recess 15 of the bushing , the ends of the arms 16, 17 on the outer ring ■ of the bearing; are attached. The inner ring of the ball bearing rotates with the bushing, while the outer ring remains stationary.

de-attorney

Claims (4)

Paientan.i'ΊΙΙθ O 1 O O / Π1 Ο Dip) .- ing. H. MITSCHERLIC "O I O Ak" ... "Dfcjy.-leg. K. Gyj! 3CHMANH ,, '■ -i · "I η Ϊ Br" km · v-t W 1 * 0 »δ λ'Λ August 17, 1981 Pohjoirt.«! IS. S ISiÄlÄÄ SF-oo2oo H.elsinki 2o / Finland Patent claims: 1. A device for adjusting the cutting height / for a lawnmower of the horizontal type, - at the one that protrudes vertically downwards from the motor 5 · Treilwelle from a spindle protruding from the motor and from one surrounding the spindle, in the longitudinal direction the spindle is movable bushing, where the Knife is attached to the lower end of the socket. "". " organs transmitting the rotary motion between the spindle and the bushing for transmitting the rotary motion of the Spindle on the socket are provided ,, g e k e η η ζ ei ch η e t in that it is between the spindle (1, 3) and the socket - (7) resilient 'locking elements (11, 13, 20, 21) are used for releasable locking of the · Bushing in the desired position in the longitudinal direction of the spindle and that the outer surface of the bushing is one with the Circumferential rectified groove (15), in which groove a projection (16, 17) of the adjusting lever (18, 19) . penetrates the inevitable displacement of the socket out of the one setting position to the other along the spindle (1, 3). 2. A lawn mower according to claim 1, characterized in that the resilient Locking members between the spindle (1, 3) and the bushing (7) made in the inner surface of the bushing in the Direction of the axis at a distance from each other 'located depressions (11, 22) and from on the outer surface " the spindle, at least one projection (l4, 20) which fits into the recesses of the bushing, exist, wherein the projection (14) or the sections between the recesses (11, 12) are resilient. . 3 A lawn mower according to claim 1, ' characterized in that the projection of the setting lifter (18, 19) consists of two rod-like arms (16, 17) which are oriented transversely in relation to the spindle Adjusting levers are attached and the ends of which are directed radially in relation to the spindle. ■ 4. A lawn mower according to claim 3, characterized in that the ends of the rod-like arms (16, 17) are attached to a ball bearing (23) ■ which is partially in a groove (15) of the . Socket is located.