EP3456481A1 - Manually operated work device - Google Patents

Abstract

A hand-held implement (1) has an internal combustion engine (10) with a cylinder (11). There is a removable cover (13) is provided, which is fixed by a closure (15). The closure (15) comprises a tensioning element (21) which is rotatable about an axis of rotation (56) and, in the locked position of the closure (15), is supported on a tensioning contour (16). The closure (15) has an elastic damping element (17) for vibration-damping fixing of the lid (13). The damping element (17) is held on a portion (41) of the cylinder (11) in the axial direction of the axis of rotation (56). During a rotation from the unlocked position (21) into the locked position (22), the clamping element (21) is moved by the clamping contour (16) in the axial direction of the axis of rotation (56). In the locked position (22) of the closure (15), the tensioning element (21) biases the section (41) of the cylinder (11) in the axial direction of the axis of rotation (56) between a first installation (19) and a second installation (20) Damping element (17). The clamping element (21) is held in the unlocked position (23) of the closure (15) on the damping element (17) on the cylinder (11).

Description

The invention relates to a hand-held implement of the type specified in the preamble of claim 1.

Hand-held implements with an internal combustion engine typically have one or more removable covers to facilitate maintenance and cleaning of the components of the implement. Such removable cover are known for example for the air filter box. By removing the air filter box lid, the air filter is accessible and can be cleaned and replaced if necessary. Also on the cylinder cleaning, in particular the cooling fins of the cylinder may be necessary. Also, the cylinder is therefore often arranged under a removable cover. For a good accessibility of the spark plug and the spark plug can be arranged under a lid of the implement. The spark plug can be arranged, for example, under the same cover as the cylinder or as the air filter. It is known to carry out such closures with a rotatable actuator.

The invention has for its object to provide a hand-held implement of the generic type, which has a simple and advantageous structure and allows easy handling.

This object is achieved by a hand-held implement with the features of claim 1.

It is envisaged that the closure has an elastic damping element for vibration-damping fixation of the lid. The damping element has a system for supporting the lid and a second system for supporting the clamping element. Lid and clamping element need not be supported directly on the damping element, but can also be indirectly supported by other elements on the damping element. It is envisaged that the damping element is held in the axial direction of the axis of rotation of the closure at a portion of the cylinder. Upon rotation of the clamping element from the unlocked position of the closure in the locked position of the closure, the clamping element is moved by the clamping contour in the axial direction of the axis of rotation. This axial movement of the clamping element causes the clamping element in the locked position of the closure clamps the portion of the cylinder in the axial direction of the axis of rotation between the first system and the second system of the damping element. In the unlocked position of the closure, the clamping element is held on the damping element on the cylinder.

The damping element reduces the transmission of vibrations from the cylinder to the cover. Characterized in that the damping element is held on the portion of the cylinder and the clamping element is held in the unlocked position of the closure on the damping element, only the cover is to be removed. The other components of the closure, namely in particular the tensioning element and the damping element, remain on the cylinder. Loss of these components is thereby reliably prevented. At the same time results in a simple design of the lid. To fix the lid, the operator only has to put on the lid and turn the clamping element about its axis. An assembly of the clamping element or the damping element on the cylinder or cover is not necessary because the clamping element and the damping element are already held on the cylinder. This results in a simple structure and easy operation of the closure. The lid itself can be easily formed. Because the clamping element is held on the damping element via the cylinder, the clamping element is opposite to the Cylinder mounted vibration damped, and the transmission of vibrations via the clamping element on the lid is reduced.

Advantageously, the clamping element on a clamping portion, a counter-holder and a shaft. The clamping portion advantageously has at least one locking element, which is supported in the locked position of the closure on the clamping contour. The at least one locking element and the counter-holder are connected to each other via the shaft, and the shaft projects at least partially through the damping element. The locking element and the counter-holder are arranged in particular on opposite axial ends of the clamping element. The locking element and the counter-holder act advantageously from opposite sides of the damping element and the cover and press so lid and damping element in the locked position of the closure against each other.

Advantageously, the damping element has an opening in which the shaft is arranged. The region of the damping element surrounding the opening preferably at least partially covers the contour of the clamping section in the unlocked position of the closure and thereby secures the clamping element in the axial direction of the axis of rotation on the damping element. The clamping section thus engages behind the damping element adjacent to the opening. Additional elements for securing the clamping element on the damping element can be omitted thereby. Due to the elasticity of the damping element assembly of the clamping element on the damping element is still possible. The damping element is in particular formed in one piece, and the mounting of the clamping element on the damping element takes place under elastic deformation of the damping element.

Advantageously, the damping element has a slot which lies in a position of the closure at least partially in register with the at least one locking element. The slot is advantageously dimensioned so that the clamping portion for mounting the clamping element on the damping element under elastic Deformation of the damping element can be pushed through the slot when the damping element is not held on the cylinder.

The damping element is advantageously arranged in a receptacle of the cylinder. In order to avoid that the clamping element can be disassembled from the damping element with deformation of the damping element, when the damping element is held on the cylinder, it is provided that the recording limits the elastic deformation of the damping element transverse to the axis of rotation and in particular transversely to the longitudinal direction of the slot, in that the clamping element is held in a form-fitting manner on the damping element when the damping element is arranged in the receptacle of the cylinder. In a damping element mounted on the cylinder, therefore, the clamping element can not be dismantled from the damping element. About the recording a backup of the position of the damping element and the clamping element in the direction of the axis of rotation relative to the cylinder is achieved in a simple manner.

Advantageously, the recording causes a rotation of the damping element about the axis of rotation. This ensures that the damping element when turning the clamping element can not rotate with the clamping element. This ensures that a defined relative movement between the clamping element and the damping element takes place. A relative movement between the damping element and the hot during operation and after switching off the engine cylinder is thereby avoided. Thereby, the wear of the damping element can be reduced.

The fact that the damping element is secured against rotation relative to the cylinder, the position of the clamping element can be secured in the unlocked or locked position via a latching device between the clamping element and the damping element.

The receptacle preferably also limits or prevents bulging of the damping element. The positive rotation lock is compared to a rotation of the damping element via axial pressure advantageous because even with reduced axial pressure of the damping element, in particular in the unlocked position of the closure, there is a rotation lock for the damping element.

Advantageously, the damping element is inserted in a direction of insertion into the receptacle. The slot preferably runs approximately parallel to the insertion direction. As a result, extending in the insertion direction sides of the recording in a simple manner prevent bulging of the damping element and secure the damping element in its rotational position.

Advantageously, at least one disc, in particular a disc made of metal, is arranged between the counter holder and the second abutment of the damping element. The disc reduces the wear between the anvil and the damping element. The counter-holder rotates advantageous with the at least one locking element about the axis of rotation of the clamping element. Due to the arrangement of the very hot cylinder in operation, the damping element is thermally highly loaded and thus susceptible to wear. About the at least one disc between the counter-holder and the second system of the damping element, this wear can be reduced. By selecting a suitable friction pair of counter-holder and disc, the operating forces that are to be applied for actuating the closure, can be selectively increased or decreased, so that an ergonomic operation of the closure can be made possible.

Advantageously, a stop is formed between the clamping element and the damping element, which determines the position of the clamping element relative to the first bearing of the damping element relative to the axial direction of the axis of rotation so that in the unlocked position of the closure with the lid on the measured in the axial direction of the axis of rotation distance between the locking element and the anvil greater than the measured in the axial direction of the axis of rotation smallest distance between the clamping contour and the anvil. The distance between the locking element and the counter-holder is advantageously at least 1 mm, preferably at least 2 mm larger than the distance between clamping contour and counter-holder. Because the distance between the locking element and the counter-holder is greater than the distance between the clamping contour and the counter-holder, the at least one locking element projects beyond the lowest point of the clamping contour when the lid is attached. The distances between the locking element and the counter-holder or between clamping contour and counter-holder are preferably measured at unloaded damping element. As a result, the locking element already projects axially into the region or to the height level of the clamping contour when the cover is placed on the working device, when the cover has not yet been pressed onto the damping element. To fix the lid, the operator therefore only has to put on the lid and turn the clamping element into the locked position. A pressing of the lid is not necessary because the locking element is already axially above the clamping contour when placing the lid and the clamping contour in the lid upon rotation of the clamping element in the locked position, the lid automatically presses against the damping element. This ensures easy handling of the closure.

Advantageously, the stop between the clamping element, in particular the clamping section, and the damping element also ensures that the locking element has a distance to the damping element in the unlocked state. The distance is advantageously both in the attached lid and removed cover. In this distance between the locking element and the damping element, the clamping contour engages and moves the clamping element during further rotation up to the locked position of the clamping element in the axial direction of the axis of rotation.

Advantageously, the tensioning element has means for adjusting the tensioning element between the unlocked position and the locked position of the closure. The means for adjusting the clamping element may preferably have an engagement contour for Include engagement of a tool. Also, a gag on which the operator can operate the clamping element directly, may be advantageous. The means for adjusting the tensioning element are preferably arranged on the tensioning section. It may be advantageous to form the locking element and the means for adjusting the clamping element on a component. The clamping contour and the means for adjusting the tensioning element are advantageously provided at the same time on the lid, preferably on the side of the closure projecting towards the outside of the housing. The counter-holder is advantageously arranged on the other, arranged inside the housing side of the closure. Preferably, the means for adjusting the tension member and the anvil are disposed on opposite sides of the portion of the cylinder and on opposite sides of the lid. Advantageously, the means for adjusting the clamping element are arranged at one end of the clamping element, and the counter-holder is arranged on the other, in particular the projecting into the housing end of the clamping element. The means for adjusting the clamping element and the counter-holder are advantageously provided on opposite sides of the shaft.

Advantageously, the closure has means for securing the rotational position of the clamping element in the unlocked position. This ensures that the clamping element does not rotate in the unlocked position of the closure relative to the damping element. If the lid is placed in the unlocked position of the clamping element, then the clamping element is in the intended position and can be inserted directly through a housing opening. The housing opening is advantageously in coincidence with the clamping section and in particular adjacent to the clamping contour. Advantageously, a locking device acting between the clamping element and the damping element is provided to secure the rotational position of the clamping element. Advantageously, a detent position is assigned to the position of the clamping element in the unlocked position. In a preferred embodiment, a further detent position is assigned to the position of the tension element in the locked position. About the locking device between the clamping element and the damping element so that a position assurance is achieved in the locked position. The angle between the two locking positions corresponds advantageously to the Angle by which the clamping element between the unlocked position and the locked position is to be rotated about the axis of rotation. The angle between the unlocked and locked position is in particular less than 270 °, particularly advantageously less than 180 °. Preferably, a further latching device is formed on the clamping contour and acts between the locking element and the lid. The further latching device advantageously has a latching position, which is associated with the locked position of the closure.

A simple design results when the latching device, which secures the rotational position of the clamping element in the unlocked position, between the shank of the clamping element and the opening of the damping element, in particular the peripheral contour of the opening of the damping element is formed. In an alternative advantageous design, it is provided that this latching device is formed between the counter-holder and the damping element.

Advantageously, the damping element is at least partially against a cooling rib of the cylinder. Preferably, a receptacle in which the damping element is arranged, formed on a cooling fin of the cylinder. The damping element advantageously has a limit stop which limits the insertion depth into the receptacle of the cylinder. In a particularly advantageous design, the damping element abuts the limit stop on the cooling rib of the cylinder.

Advantageously, the damping element is aligned so that the second system of the damping element extends inclined to at least one cooling fin of the cylinder. This is particularly advantageous when the cylinder longitudinal axis is arranged inclined in the housing, so that the cooling fins with respect to the housing top are inclined. Preferably, the damping element is chamfered on a transverse side. The bevel is advantageously designed so that the damping element does not or only slightly protrudes into a cooling channel formed between the cooling fins. Prefers protrudes the damping element by less than 2 mm in the cooling air channel formed between the cooling fins.

Advantageously, the clamping contour is arranged on the lid. In a preferred embodiment, the clamping contour is formed integrally with the lid. Advantageously, the contour of the lid together with the clamping contour, in particular by injection molding, preferably made of plastic.

The closure advantageously consists of the clamping contour, the clamping element and the damping element. In the unlocked position of the closure, the clamping contour is advantageously removable together with the lid, while the remaining components of the closure, namely the clamping element and the damping element, remain on the cylinder and are held thereon.

Advantageously, the implement has a cover for the closure, which is held on the lid and at least partially covers at least one locking element. In particular, if an engagement contour for engagement of a tool is provided on the clamping element, which is formed separately from the locking element, the operator does not need the locking elements for operating the closure. The fact that the locking elements and thus also the clamping contour are at least partially, preferably largely or completely covered by the cover, the tendency to fouling on locking elements and clamping contour is reduced.

The clamping contour is advantageously formed by at least one ramp extending in the circumferential direction to the axis of rotation. This results in an approximately helical, in a section in the circumferential direction wedge-shaped course of the clamping contour.

Fig. 1

eine perspektivische Darstellung eines Arbeitsgeräts,

Fig. 2

eine ausschnittsweise Darstellung des Arbeitsgeräts aus Fig. 1 von oben,

Fig. 3

eine ausschnittsweise Schnittdarstellung entlang der Linie III-III in Fig. 2,

Fig. 4

eine perspektivische Darstellung des Deckels im Bereich des Verschlusses,

Fig. 5

eine Draufsicht auf den Ausschnitt des Deckels aus Fig. 4,

Fig. 6

eine perspektivische Darstellung der Oberseite des Deckels,

Fig. 7

eine perspektivische Darstellung der Unterseite des Deckels,

Fig. 8

eine perspektivische Darstellung von Dämpfungselement, Spannelement und Scheibe des Verschlusses,

Fig. 9

eine perspektivische Darstellung von Spannelement und Scheibe,

Fig. 10 und Fig. 11

perspektivische Darstellungen des Dämpfungselements,

Fig. 12

eine perspektivische Darstellung der Scheibe,

Fig. 13

eine perspektivische Darstellung einer Abdeckung,

Fig. 14

einen Schnitt durch Dämpfungselement, Spannelement und Scheibe entlang der Linie XIV-XIV in Fig. 15,

Fig. 15

einen Schnitt durch Dämpfungselement und Spannelement entlang der Linie XV-XV in Fig. 14,

Fig. 16

eine perspektivische Darstellung eines Ausführungsbeispiels von Dämpfungselement, Spannelement und Scheibe eines erfindungsgemäßen Verschlusses,

Fig. 17

eine Seitenansicht von Dämpfungselement, Spannelement und Scheibe aus Fig. 16,

Fig. 18

einen Schnitt entlang der Linie XVIII-XVIII in Fig. 17,

Fig. 19

eine perspektivische Darstellung eines weiteren Ausführungsbeispiels von Dämpfungselement, Spannelement und Scheibe eines erfindungsgemäßen Verschlusses,

Fig. 20

eine Seitenansicht von Dämpfungselement, Spannelement und Scheibe aus Fig. 19,

Fig. 21

einen Schnitt entlang der Linie XXI-XXI in Fig. 20.

Embodiments of the invention are explained below with reference to the drawing. Show it:

Fig. 1

a perspective view of a working device,

Fig. 2

a partial view of the implement from Fig. 1 from above,

Fig. 3

a partial sectional view taken along the line III-III in Fig. 2 .

Fig. 4

a perspective view of the lid in the region of the closure,

Fig. 5

a plan view of the cutout of the lid Fig. 4 .

Fig. 6

a perspective view of the top of the lid,

Fig. 7

a perspective view of the underside of the lid,

Fig. 8

a perspective view of the damping element, clamping element and disc of the closure,

Fig. 9

a perspective view of clamping element and disc,

10 and FIG. 11

perspective views of the damping element,

Fig. 12

a perspective view of the disc,

Fig. 13

a perspective view of a cover,

Fig. 14

a section through damping element, clamping element and disc along the line XIV-XIV in Fig. 15 .

Fig. 15

a section through the damping element and clamping element along the line XV-XV in Fig. 14 .

Fig. 16

a perspective view of an embodiment of damping element, clamping element and disc of a closure according to the invention,

Fig. 17

a side view of damping element, clamping element and disc Fig. 16 .

Fig. 18

a section along the line XVIII-XVIII in Fig. 17 .

Fig. 19

a perspective view of another embodiment of damping element, clamping element and disc of a closure according to the invention,

Fig. 20

a side view of damping element, clamping element and disc Fig. 19 .

Fig. 21

a section along the line XXI-XXI in Fig. 20 ,

Fig. 1 shows in perspective a hand-held implement 1. The implement 1 is in the embodiment, a portable, hand-held chainsaw. However, the hand-held implement may be another implement such as a brushcutter, grinder, blower, or the like. The working device 1 has a housing 2, in which an internal combustion engine 10 is arranged. The internal combustion engine 10 is in Fig. 1 only partially visible between the housing parts of the housing 2. To guide the Working device 1, a rear handle 3 and a handle tube 4 are provided. The implement 1 has a guide rail 8, on which a saw chain 9, shown schematically, is driven in rotation. The saw chain 9 is driven by the internal combustion engine 10. At the saw chain 9 facing side of the handle tube 4, a hand guard 5 is arranged, which is fixed to the housing 2. The hand guard 5 is used in a preferred embodiment for actuating a brake device for the saw chain 9. At the rear handle 3, a throttle 6 and a throttle lever lock 7 are pivotally mounted. The throttle lever 6 serves to control the internal combustion engine 10.

The housing 2 comprises a lid 13, which is fixed via a detachable closure 15. The cover 13 forms part of the outer shell of the working device 1. The cover covers the internal combustion engine 10 of the working device 1 at least partially. In the exemplary embodiment, the cover 13 forms part of the housing 2. The housing 2 is composed of several components, which may also have other functions. The housing 2 is in particular not a closed housing. The housing 2 further comprises a releasably fixed air filter cover 14. On the cover 13, an opening 58 is provided, which is arranged in a recess 57.

As Fig. 2 shows, protrudes through the opening 58 an actuating part of a decompression valve 70 of the internal combustion engine 10. The implement 1 has an in Fig. 2 schematically shown longitudinal center plane 67, which is parallel to the plane of the guide rail 8 (FIG. Fig. 1 ) runs. The rear handle 3 is advantageously approximately parallel to the longitudinal center plane 67, preferably at least partially in the longitudinal center plane 67. The closure 15 and the decompression valve 70 are arranged approximately symmetrically to the longitudinal center plane 67 and on both sides of the longitudinal center plane 67. The closure 15 has an engagement contour 42 for engagement of a tool. In the embodiment, the engagement contour 42 is formed as a slot for engagement of a screwdriver. As Fig. 2 Also shows, extends outside the engagement contour 42 a cover 13 fixed to the cover 43, which will be described in more detail below.

Fig. 3 shows the design of the closure 15 in detail. As Fig. 3 shows, the closure 15 comprises a damping element 17, a clamping element 21 and an integrally formed on the lid 13 clamping contour 16. The damping element 17 is held on a cylinder 11 of the internal combustion engine 10. The cover 13 covers the cylinder 11 of the internal combustion engine 10 at least partially. The cylinder 11 has a plurality of cooling fins 12, between which cooling air passages 52 extend. Through the cooling air ducts 52, a fan wheel, which is driven by the internal combustion engine 10 and not shown in the figures, conveys cooling air. On one of the cooling fins 12, in the embodiment on the upper, the cover 13 facing the cooling fin 12, a receptacle 18 for the damping element 17 is formed. The damping element 17 has a first portion 33 and a second portion 34. Between the sections 33 and 34 extend webs 35, which are set back relative to the outer contour of the sections 33 and 34 and thus form recesses 40 into which a portion 41 of the cylinder 11 engages. The damping element 17 is in an in Fig. 2 insertion direction 49 shown in the receptacle 18 can be inserted and disassembled in the opposite direction from the receptacle 41. Further means for fixing the damping element 17 in the receptacle 18 are advantageously not provided. At the portion 41 of the cylinder 11, an opening 76 is formed, through which the damping element 17 protrudes.

The clamping element 21 has a shaft 26, a clamping portion 27 and a counter-holder 28. The clamping portion 27 and the counter-holder 28 are arranged at opposite ends of the shaft 26 and connected to each other via the shaft 26. Clamping portion 27 and counter-holder 28 are advantageously formed at least partially with the shaft 26 of a single part. The clamping portion 27 has at least one locking element 29. In the exemplary embodiment, two opposing locking elements 29 are provided. Also, a different number of locking elements 29 may be advantageous. The at least one locking element 29 is expediently designed as a separate part from the shaft 26 and inserted or pressed into the clamping section 27.

The damping element 17 has a first system 19, which is supported on the cover 13. In the exemplary embodiment, the cover 13 abuts directly against the first abutment 19 of the damping element 17. The damping element 17 also has a second system 20, on which the counter-holder 28 is supported directly or indirectly. In the exemplary embodiment, a disc 32 is disposed between the counter-holder 28 and the second system 20. The disk 32 is made of metal. The width m of the disc 32 is greater than a width k of the aperture 76 in the portion 41 of the cylinder 11. The width m and the width k are measured in the same direction perpendicular to the axis of rotation 56 and in particular between the two recesses 40. The width m of the disc 32 is advantageously at least 1.2 times, in particular at least 1.4 times the width k of the opening 76. The fact that the width m of the disc 32 is greater than the width k of the opening 76, avoids that the damping element 17 deformed and with its first portion 33 can be partially pulled into the opening 76. As a result, the wear of the damping element 17 is reduced.

Between the systems 19 and 20 is the recess 40 into which the portion 41 of the cylinder 11 projects. The system 19 abuts against the inside of the lid 13. On the outside of the lid 13, the clamping contour 16 is formed. As Fig. 3 shows, the clamping contour 16 extends ramped or wedge-shaped in the circumferential direction. The clamping contour 16 is advantageously formed helically around a rotational axis 56 of the clamping element 21. In this case, the clamping contour 16 extends advantageously only over a partial angle about the axis of rotation 56. The clamping contour 16 extends in a ramp around the axis of rotation 56. The partial angle is preferably smaller than the angle of rotation to rotate the clamping element 21 between the unlocked position and locked position is. In the remaining peripheral portion between partial angle and angle of rotation is a detent recess 46 ( Fig. 4 ) for the locking element 29, which prevents a sliding down, ie a turning back of the locking element 29 on the ramp of the clamping contour 16.

Fig. 3 shows the closure 15 in the unlocked position 23. In this position, the clamping portion 27 is completely in register with an opening formed in the cover 13 through-hole 47. The locking element 29 is not in contact with the clamping contour 16. The locking element 29 has a parallel to the axis of rotation 56 measured Distance a to the counter-holder 28. The clamping contour 16 has the counter-holder 28 a smallest distance b. The smallest distance b is advantageously measured at the region of the clamping contour 16, which first comes into coincidence with the locking element 29 when the clamping element 21 is rotated from the unlocked position 23 into the locked position 22. The distance b is smaller than the distance a, so that the clamping contour 16 can engage in the rotation of the clamping element 21 under the locking element 29. For this purpose, the clamping element 21 is secured in its position in the direction of the axis of rotation 56 relative to the damping element 17, as will be described in more detail below. Fig. 3 shows the arrangement of the closure 15 after merely placing the lid 13. The lid 13 has not been pressed down by the operator, so that the damping element 17 is not compressed by the lid 13.

As Fig. 3 also shows, has the locking element 29 in the in Fig. 3 Due to the fact that the locking element 29 is located above the damping element 17, the clamping contour 16 can readily engage under the locking element 29, that is to say between the damping element 17 and the locking element 29. The position designations "above" or "above" and "below" or "below" refer to a vertical arrangement of the axis of rotation 56 and an arrangement of the clamping portion 27 on the anvil 28. This position is in Fig. 3 shown. In this position, the axis of rotation 56 is in the effective direction of gravity, and the clamping element 21 supports its gravity advantageous on the clamping portion 27 against the damping element 17 from.

If the clamping element 21 is rotated in the direction of the locked position 22, then the locking element 29 comes into contact with the clamping contour 19. The clamping contour 19 moves the clamping element 21 in the direction of the axis of rotation 56 in a clamping direction 24. The clamping direction 24 is directed from the counter-holder 28 to the clamping portion 27. As a result, the cover 13 is pressed over the clamping contour 16 to the cylinder 11 and thereby compresses the damping element 17. The portion 41 of the cylinder 11 remains stationary while the clamping element 21 in Fig. 3 upwards and the lid 13 in Fig. 3 down, ie in the direction of the cylinder 11, move. As Fig. 3 also shows, the clamping portion 27 is disposed in a recess 25 of the lid 13, of the cover 43 (FIG. Fig. 2 ) is partially closed.

As Fig. 3 Also shows, the damping element 17 has on its side facing away from the lid 13 a chamfer 37. Wie Fig. 3 Therefore, the damping element 17 is inclined to the cooling channels 52. The bevel 37 is arranged so that the damping element 17 does not or only slightly into the cooling air passage 52 protrudes. The chamfer 37 is advantageously designed so that the damping element 17 protrudes less than 2 mm in the cooling air channel 52 formed between the cooling fins 12. In the exemplary embodiment, the chamfer 37 lies in a plane with the underside of the adjacent cooling rib 12. The chamfer 37 is arranged on the arranged in the receptacle 18, the first portion 33 of the damping element 17.

Fig. 4 shows the lid 13 with the protruding to the outside of the housing 2 portion of the clamping element 21. Wie Fig. 4 shows, two opposing locking elements 29 are provided. In the in Fig. 4 shown unlocked position 23 are the locking elements 29 as well as the clamping portion 27 of the clamping element 21 in registration with the insertion opening 47 of the lid 13. In the unlocked position 23 of the lid 13 can thereby placed on the chip element 21 or lifted from the clamping element 21. As Fig. 4 Also shows, in the circumferential direction adjacent to each locking element 29 each have a clamping contour 16 is arranged which extends helically. At each clamping contour 16 includes a detent recess 46, which defines the locked position of the closure 15.

Fig. 5 shows the locked position 22 schematically with a dashed line. In the locked position 22, the locking elements 29 are in the associated locking recesses 46. In 4 and FIG. 5 are also latching openings 48 of the lid 13 shown in which the cover 43 is to be fixed.

In the exemplary embodiment, the clamping element 21 for locking in a rotational direction 45 to rotate about the rotation axis 56. In the embodiment, the direction of rotation 45 extends in a view of the lid 13 from above in a clockwise direction. As the 4 and 5 Also show, 13 elevations 73 are formed on the lid, which prevent rotation of the clamping element 21 in the opposite direction, ie counterclockwise in the exemplary embodiment, constructively. In the exemplary embodiment, the elevations 73 also serve to position the cover 43. Between the unlocked position 23 and the locked position 22, the clamping element 21 is to be rotated in the exemplary embodiment by 90 °. However, another angle of rotation between the unlocked position 23 and the locked position 22 may be advantageous. However, the angle of rotation is less than 360 °, so that the clamping element 21 between the unlocked position 23 and the locked position 22 is to rotate by less than one revolution. In particular, the angle of rotation is smaller than 180 °, so that the clamping contour 16 extends only on one side of the insertion opening 47.

The 6 and 7 show the design of the lid 13 in detail. As Fig. 6 shows, the insertion opening 47 is formed toggle-shaped with an approximately circular central region and two thereof radially outwardly extending narrower areas thereof. The contour of the insertion opening 47 advantageously corresponds approximately to the contour of the clamping section 27 including the locking elements 29 Fig. 6 and Fig. 7 are also the locking openings 48 are shown for the cover 43. In the 6 and 7 In addition, the opening 58 for the decompression valve 70 can be seen. When the cover 13 is removed on the cover 13, only the insertion opening 47 and the clamping contour 16 of the closure 15 is formed. The other components of the closure 15 are held on the cylinder 11.

In Fig. 7 Support pins 74 and 75 are arranged. In the embodiment, three support pins 74 and a support pin 75 are provided, which span approximately a square. The support bolts 74 and 75 are supported on damping elements, not shown, connected to the cylinder 11 or with a crankcase, not shown components of the implement 1 and thus support the cover 13 in the axial direction of the axis of rotation 56. In the embodiment dip the support bolts 74 in rubber-mounted Sleeves and thus secure the cover 13 in the direction perpendicular to the axis of rotation 56. The support pin 75 immersed in a damping element, which rests only on a rib of the cylinder 11, so that the lid 13 is supported exclusively in the axial direction of the axis of rotation 56.

Fig. 8 shows the components held on the cylinder 11, namely the damping element 17, the clamping element 21 and the disc 32nd Fig. 8 shows the arrangement in a preassembled state, in which the arrangement in the receptacle 18 of the cylinder 11 (FIG. Fig. 3 ) in the Fig. 2 shown insertion direction 49 can be inserted.

As the 8 and 9 show, the disc 32 has a rectangular shape. The disk 32 is arranged in a recess 64 of the damping element 17. The bottom of the recess 64 forms the second plant 20. The recess 64 is how Fig. 10 shows, surrounded by a peripheral wall 65. The peripheral wall 65 encloses the disc 32 at its circumference closely or at a very small distance, so that the disc 32 is secured against rotation by the peripheral wall 65 of the recess 64 relative to the damping element 17.

As Fig. 9 shows, the shaft 26 has a non-round, preferably polygonal, in the embodiment, a square-shaped cross-section. The disk 32 has a Opening 72 ( FIGS. 9 and 12 ), which has a round cross section in the embodiment. The opening 72 is dimensioned so that the clamping element 21 can rotate freely in the opening 20. As the 8 and 9 also show, the counter-holder 28 is formed in the embodiment as a disc with a circular cross-section. The shaft 26 has a first end 30, on which the clamping portion 27 is arranged. The shaft 26 also has a second end 31, on which the counter-holder 28 is arranged. The anvil 28 and the clamping portion 27 are thus arranged at opposite ends of the shaft 26. The shaft 26 protrudes, as Fig. 8 combined with Fig. 9 shows, through the damping element 17th

As the FIGS. 8 and 10 show, between the portions 33 and 34 of the damping element 17, the recesses 40 are formed, in which the portion 41 of the cylinder 11 engages ( Fig. 3 ). At the damping element 17 also has a limit stop 38 is formed, on which the first portion 33 is made thickened. The limit stop 38 limits the insertion depth of the damping element 17 into the receptacle 18 (FIG. Fig. 3 ). As the FIGS. 8 and 10 show, the chamfer 37 is formed on a transverse side 51 of the damping element 17. The sections 33 and 34 are connected by two webs 35. The webs 35 extend between the two recesses 40. In the embodiment, the first portion 33 has a rectangular cross section, while the second portion 34 has a round cross section.

In particular Fig. 11 shows, the damping element 17 has a slot 36. The webs 35 are separated by the slot 36 from each other. The slot 36 extends in the embodiment over the entire diameter of the second portion 34 and extends through the second portion 34 in a direction perpendicular to the axis of rotation 56 (FIG. Fig. 9 ). As Fig. 11 Also shows, the damping element 17 has an opening 39 for the shaft 26. At the second portion 34 adjacent to the opening 39, on which the opening surrounding region of the damping element 17, a stop 50 is formed. In the exemplary embodiment, the stop 50 is formed as a recess of the damping element 17. The stop 50 covers the contour of the clamping portion 27 at least in unlocked position 23 of the shutter 15 at least partially. In the exemplary embodiment, the stop 50 covers the contour of the clamping section 27 in each position of the clamping element 21. The clamping section 27 of the clamping element 21 lies against the stop 50 (FIG. Fig. 9 ) on. As a result, the clamping element 21 is secured against position relative to the damping element 17 in the direction of the axis of rotation 56. As Fig. 11 Also shows, the opening 39 has a square cross section, which corresponds to the cross section of the shaft 26 with a small clearance. The opening 39 and the shaft 26 form a latching device 53 due to their coordinated, non-circular cross-section (FIG. Fig. 14 ), which defines four detent positions of the shaft 26 with respect to the damping element 17 in the embodiment. Due to the symmetrical design of the clamping element 21, two of the locking positions of the unlocked position 23 and the other two locking positions of the locked position 22 of the closure 15 are assigned. Characterized in that the locked position 22 is associated with a detent position, the shaft 26 is in the locked position 22 with little play in the opening 39. Thus, the damping element 17 in the locked state 22, ie also during operation of the implement 1, transverse to the axis of rotation 56 relaxed at the opening 39, and the load of the damping element 17 and thus the wear are reduced. In the exemplary embodiment, an angle of 90 ° is provided between the locked position 22 and the unlocked position 23 of the at least one locking element 29. This angle thus corresponds to the angle between the locking positions of the locking device 53.

As Fig. 13 shows, the cover 43 has an opening 44 through which the engagement contour 42 is accessible from the outside. The locking elements 29 are largely covered by the cover 43, in particular completely covered, in particular Fig. 2 shows. On the cover 43 latching elements 71 are formed, which can be inserted into the latching openings 48 of the lid 13 and latched there on the lid 13 ( 4 and 5 ). Through the cover 43, the view of the locking element 29 and the insertion opening 47 of the lid 13 is difficult or prevented. A simple placement of the lid 13 is still possible because the locking device 53 between clamping element 21 and damping element 17 prevents inadvertent rotation of the clamping element 21 during or after the removal of the lid 13. As a result, the position of the locking element 29 after removal of the cover 13 corresponds to the position before re-attaching the cover 13. Since the cover 13 can only sit or remove in a single orientation, the locking elements 29 and the insertion opening 47 are automatically aligned with each other , A visual inspection of the orientation of the locking element 29 or even a rotation of the clamping element 21 is unnecessary in order to set the lid 13 correctly on the damping element 17.

The FIGS. 14 and 15 show clamping element 21, damping element 17 and disc 32 in the assembled state. As the FIGS. 14 and 15 show, the clamping element 21 is constructed of a support member 59 through which a bolt 60 protrudes. The support member 59 forms the counter-holder 28, the shaft 26 and the central part of the clamping portion 21. counter-holder 28, shaft 26 and a portion of the clamping portion 21 are thus constructed in one piece. The bolt 60 forms the two locking elements 29. The bolt 60 is inserted through an opening 61 of the support member 59 and extends transversely, in the embodiment perpendicular to the axis of rotation 56. It can be provided that the support member 59 initially mounted without the bolt 60 on the damping element 17 and the bolt 60 is inserted into the carrier component 59 only after the mounting of the carrier component 59 on the damping element 17. Alternatively, the clamping element 21 can be pushed through the damping element 17 in an advantageous design, including the bolt 60. The damping element 17 is designed so that the slot 36 and the opening 39 can be widened under elastic deformation of the damping element 17, so that at least the tensioning section 27 can advantageously also be inserted with assembled locking elements 29. Subsequently, the assembly of damping element 17, clamping element 21 and disc 32 in the insertion direction 49 (FIG. Fig. 2 ) in the receptacle 18 of the cylinder 11 ( Fig. 3 ) assembled.

As the 10 and 11 The slot 36 thus runs parallel to the longitudinal walls of the receptacle 18. If the damping element 17 is mounted on the cylinder 11, the slot 36 can no longer be significantly widened. As Fig. 3 shows, the damping element 17 rests with its transverse sides 51 in the exemplary embodiment on the side walls of the receptacle 18. The receptacle 18 prevents both a widening of the damping element 17 and a rotation of the damping element 17 about the axis of rotation 56. The slot 36 is dimensioned so that the locking element 29 and the clamping element 21 can only be pushed through the slot 36 when the Damping element 17 is not held on the cylinder 11. After assembly of the damping element 17 on the cylinder 11 is a mounting or dismounting of the clamping element 21 on the damping element 17 is no longer possible.

As the FIGS. 14 and 15 show, the counter-holder 28 and the stopper 50, the axial position of the clamping element 21 on the damping element 17 fixed. In Fig. 15 is also the locking device 53 shown, which is formed between the shaft 26 of the clamping element 21 and the contour of the opening 39 in the damping element 17. As Fig. 14 shows, the clamping portion 27 has a diameter c. The diameter c is greater than the largest diameter d of the shaft 26. The diameter c is also greater than the largest diameter h of the opening 39, the in Fig. 11 is drawn. Adjacent to the anvil 28, the shaft 26 has a shoulder 62 of increased diameter, such as Fig. 14 shows. Also, the paragraph 62 secures the axial position of the locking element 21 on the damping element 17. In the exemplary embodiment, the locking element 21 without clearance, preferably with low bias voltage of the damping element 17 is mounted on the damping element 17. The counter-holder 28 has a diameter e which is significantly larger than the largest diameter d of the shaft 26 and larger than the largest diameter h of the opening 39 (FIG. Fig. 11 ).

As Fig. 14 also shows, the disc 32 extends almost the entire width and length of the recess 64. Like Fig. 14 shows is only slight play between the Washer 32 and the peripheral wall 65 is provided. The circumferential groove 63 reduces the tension in the compressed damping element 17 and reduces the wear between the disc 32 and the damping element 17 at the edge of the disc 32 Fig. 14 shows, the slot 36 extends to narrow wall portions 66 which extend to the second portion 34 to the peripheral wall 65. The wall portions 66 extend to the first portion 33 and connect the portions 33 and 34 in the region of the slot 36 with each other, as well 8 and 11 demonstrate. The sections 33 and 34 are also via the webs 35 ( Fig. 15 ) connected.

In Fig. 15 is also the bevel 37 on the transverse side 51 clearly visible.

The Fig. 16 to 21 show two further embodiments of a closure 15, wherein only the damping element 17, the clamping element 21 and the disc 32 are shown. Like reference numerals indicate corresponding elements in all embodiments. In contrast to the first embodiment, the latching device is formed in the following embodiments between the anvil of the clamping element 21 and the damping element 17.

In the in the Fig. 16 to 18 In the embodiment shown, the clamping element 21 has a counter-holder 68, which has a square contour with strongly rounded corners. The width f of the square contour of the counter-holder 68 corresponds to the distance between opposing peripheral wall portions 69 of the damping element 17. About the peripheral wall portions 69, the rotational position of the counter-holder 68 is fixed. Under elastic deformation of the peripheral wall portions 69 of the counter-holder 68 can be rotated and in this case the diagonal of the square contour between the opposite peripheral wall portions 69 are rotated through, in the exemplary embodiment in steps of 90 °. The counter-holder 68 and the peripheral wall portions 69 form a latching device 54. The first portion 33 of the damping element 17 is in the embodiment according to Fig. 16 narrower as in the embodiment of the preceding figures. Because the counter-holder 68 is not arranged in a recess with a closed peripheral wall, no peripheral wall sections project into a cooling-air channel 52 of the cylinder 11 (FIG. Fig. 3 ), so that a chamfer is not necessary. Instead of a bevel missing the peripheral wall sections 69 connecting wall sections.

In the Fig. 19 to 21 is another embodiment of damping element 17, clamping element 21 and disc 32 is shown. The clamping element 21 shown here has a counter-holder 78, whose shape corresponds to the shape of the counter-holder 68. However, the counter-holder 78 is arranged in a recess 64 which is bounded by a peripheral peripheral wall 65. The counter-holder 78 forms with the peripheral wall 65 a latching device 55. The counter-holder 78 determines rotational positions of the locking element 21, which have an angular distance of 90 ° to each other. One of the rotational positions corresponds to the unlocked position 23 of the shutter 15, and the other rotational position corresponds to the locked position 22nd

Claims (15)

A hand-operated implement having an internal combustion engine (10) for driving a tool of the implement, said internal combustion engine having a cylinder (11), the implement (1) comprising a removable lid (13) fixed by a closure (15) the closure (15) comprises a clamping element (21) which is rotatable about an axis of rotation (56), wherein the clamping element (21) in the locked position (22) of the closure (15) is supported on a clamping contour (16) and for adjustment from the unlocked position (23) to the locked position (22) by less than a full turn,
characterized in that the closure (15) has an elastic damping element (17) for vibration-damping fixing of the cover (13), that the damping element (17) has a first system (19), on which the cover (13) in the axial direction the axis of rotation (56) is supported, that the damping element (17) has a second abutment (20), on which the clamping element (21) is supported in the axial direction of the axis of rotation (56), that the damping element (17) at a portion (41 ) of the cylinder (11) is held in the axial direction of the axis of rotation (56) that the clamping element (21) upon rotation from the unlocked position (23) of the closure (15) in the locked position (22) of the closure (15) is moved by the clamping contour (16) in the axial direction of the axis of rotation (56) that the clamping element (21) in the locked position (22) of the closure (15) the portion (41) of the cylinder (11) in the axial direction of the axis of rotation ( 56) between the first system (19) and d he second system (20) of the damping element (17) clamps, and that the Clamping element (21) in the unlocked position (23) of the closure (15) on the damping element (17) on the cylinder (11) is held. Working device according to claim 1,
characterized in that the tensioning element (21) has a tensioning section (27), an anvil (28) and a shaft (26), wherein the tensioning section (27) has at least one locking element (29), wherein the at least one locking element (29) in the locked position (22) of the closure (15) on the clamping contour (16) is supported, wherein the at least one locking element (29) and the counter-holder (28) via the shaft (26) are interconnected and wherein the shaft (26) at least partially by the damping element (17) protrudes. Working device according to claim 2,
characterized in that the damping element (17) has an opening (39) in which the shaft (26) is arranged, wherein the area of the damping element (17) surrounding the opening, the contour of the clamping portion (27) in the unlocked position (21). the closure (15) at least partially covered and thereby secures the clamping element (21) in the axial direction of the axis of rotation (56) on the damping element (17). Working device according to claim 3,
characterized in that the damping element (17) has a slot (36) in a position (23) of the closure (15) at least partially in register with the at least one locking element (29), wherein the slot (36) so dimensioned in that the clamping section (27) for mounting the clamping element (21) on the damping element (17) can be pushed through the slot (36) with elastic deformation of the damping element (17) if the damping element (17) is not attached to the cylinder (17). 11) is held. Tool according to one of claims 2 to 4,
characterized in that the damping element (17) in a receptacle (18) of the cylinder (11) is arranged and that the receptacle (18) causes a rotation of the damping element (17) about the axis of rotation (56). Tool according to one of claims 2 to 5,
characterized in that between the counter-holder (28, 68, 78) and the second abutment (20) of the damping element (17) at least one disc (32) is arranged. Tool according to one of claims 2 to 6,
characterized in that between the clamping element (21) and the damping element (17) a stop (50) is formed, the position of the clamping element (21) relative to the first system (19) of the damping element (17) relative to the axial direction of Sets the axis of rotation (56) so that in the unlocked position (23) of the closure (15) with the cover (13) the distance (a) measured in the axial direction of the axis of rotation (56) between the locking element (29) and the counter-holder (28 ) is greater than the smallest distance (b) between the clamping contour (16) and the counter-holder (28) measured in the axial direction of the axis of rotation (56). Tool according to one of claims 2 to 7,
characterized in that the tensioning element (21) comprises means for adjusting the tensioning element (21) between the unlocked position (23) and the locked position (22) of the closure (15), the means for adjusting the tensioning element being mounted on the tensioning section (27 ) are arranged. Tool according to one of claims 1 to 8,
characterized in that for securing the rotational position of the clamping element (21) between the clamping element (21) and the damping element (17) acting latching device (53, 54, 55) is provided, wherein a detent position of the position of the clamping element (21) in the unlocked position (23) is associated. Tool according to claim 9,
characterized in that the latching means (53) between the shaft (26) of the clamping element (21) and the opening (39) of the damping element (17) is formed. Tool according to claim 9,
characterized in that the latching means (54, 55) between the counter-holder (28) and the damping element (17) is formed. Tool according to one of claims 1 to 11,
characterized in that the damping element (17) at least partially against a cooling rib (12) of the cylinder (11). Tool according to one of claims 1 to 12,
characterized in that the second abutment (20) extends inclined to at least one cooling rib (12) of the cylinder (11), and that the damping element (17) is chamfered on a transverse side (51). Tool according to one of claims 1 to 13,
characterized in that the clamping contour (16) on the lid (13) is arranged. Tool according to one of claims 1 to 14,
characterized in that the implement comprises a cover (43) for the closure (15) which is held on the lid (13) and at least partially covers the at least one locking element (29).

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