JPH053365B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is characterized in that a trigger is connected to a cocking member and a brake member, the brake member is arranged in a brake band surrounding a brake drum, and A power source having a driving engine of the type in which the brake member is held by a locking mechanism in a ready position with the brake band spaced apart from the brake drum against the force of a brake spring engaging the brake member. The present invention relates to a chain brake device for actuating a spring-loaded brake for a chainsaw.

[Prior Art] In the known chain brake device of the above type,
A bow-shaped disaster prevention material for protecting the hands of power chainsaws.
The bow-shaped disaster prevention member is rotated when the saw chain recoils, that is, when a kickback effect occurs, and in that case, the locking mechanism is released between the brake member and the locking member, and the brake band is rotated. , is tightly attached to the brake drum by the force acting on the brake member. In order to separate or release the brake band from the brake drum, that is, to move the chain brake device to the release position, the arcuate disaster prevention material for hand protection must be pushed back to the release position by hand against the force of the brake spring. It won't happen. Due to the relatively strong construction of the brake spring, the release of the brake band is troublesome, since a considerable amount of labor is required in order to pivot the hand protection bow. This push-back requires the operator to remove one hand from the grip, resulting in an interruption in the work flow each time the brake band is released. In some cases, the force of one hand alone is not sufficient for disassembly, so that it is necessary to support the power chainsaw beforehand on a suitable support, for example on the ground. If the chain brake system is released in successive short time intervals, the work flow is interrupted particularly frequently and for relatively long periods of time. Particularly if power chainsaws are additionally equipped with so-called one- or two-handed protection measures, i.e. if the operator's hand leaves one of the grips, a danger signal is emitted which triggers the release of the brake system. The frequency of interruptions to the work flow is especially high when These additional danger signals are necessarily accompanied by frequent release malfunctions, which require the hand protection bow to be swiveled into the release position after each release malfunction. The input and time consumption is significant.

[Problems to be Solved by the Invention] An object of the present invention is to improve the chain brake device of the type mentioned at the beginning, and to improve the brake member and the brake in order to release the brake band without significantly interrupting the flow of work. To configure a spring so that it can be easily and quickly brought into a stiffened state.

[Means for Solving the Problems] The constituent means of the present invention for solving the above-mentioned problems are such that in the braking position of the brake member, the pulling member is brought into the movement path of the entrainment element, and the entrainment element is moved by the drive engine. The main point is that the crankshaft, which is a driving member that is rotationally driven, is connected to the crankshaft so that it cannot rotate relative to the crankshaft.

[Operation] Due to the configuration of the invention, it is no longer necessary to manually move the brake member into the release position. Rather, the brake member is moved into the ready position by the action of the drive engine. For this purpose, no special labor input is required, and the operating state of the power chainsaw is easily and very quickly reestablished, so that the work flow is maintained even in the case of frequent and continuous braking. There will be no interruptions or interruptions. If the chain brake device of the present invention is used based on the fact that the brake band is easily and quickly released, the above-mentioned danger signals other than pure reaction braking can be generated without bothering the operator more than expected. The prerequisites for utilization can be obtained. For example, the very act of releasing one of the two grips of a power chainsaw (e.g. a grip with a pressure member that is pressed down by grasping the grip) can be used as a danger signal for releasing a chain brake device. Ru. In particular, to release the chain brake device,
A release action of the pressure member arranged on the rear handgrip is suitable, which need only be grasped and pressed again on the grip in order to return to the ready position. With this additional danger signal, the risk of injury is significantly reduced. Furthermore,
The chain brake device of the present invention can also be configured as an automatic reaction braking device, for example, when a hand-protecting bow-shaped disaster prevention material is used as a trigger in a power chainsaw.

[Example] Next, an example of the present invention will be explained in detail based on the drawings.

The power chainsaw 1 shown in FIG.
and a rear grip 4 extending parallel to the saw blade 3. Between the saw blade 3 and the front support grip 2, an arcuate disaster protection member 18 for hand protection extending parallel to the front support grip 2 is rotatably attached. Rear grip 4
A throttle lever 5 protruding from the lower surface of the grip and a pivotable pressure member 6 protruding from the upper surface of the grip are disposed inside. An actuating member 8 of a chain brake device 9 is connected to the pressure member 6 via a Bowden operating cable 7 that constitutes a tension node.

The chain brake device 9 consists of a lever-shaped brake element 10 which is connected to a brake spring 11 designed as a tension spring and a brake band 12 which surrounds a brake drum 13 of the power chain saw 1 . Brake band 12
The brake spring 11 is fixed to the casing 16 of the power chainsaw 1 at its ends 14, 15 remote from the brake member 10. The brake drum 13 contains therein a crankshaft 17 which is drivingly connected to the engine (not shown) of the power chainsaw 1, which crankshaft is configured as a lever and which engages the locking member 2 of the chain brake device 9.
It holds a cam-like entrainer 19 for 0.
The contour of the entrainer 19 is approximately elliptical, the ellipse having a narrow edge curved approximately in the form of a quarter circle about the entrainer axis 56, which narrow edge forms a cam base circle 57. (See Figure 6). Since the rise of the driver 19 from the cam base circle 57 to the cam apex 59 (see FIG. 7) begins only after the top dead center of the crankshaft 17 has passed, the twisting movement belongs to the expansion stroke of the crankshaft.

In the release position shown in FIGS. 1 and 2, the locking member 20 is engagedly connected to the lever-shaped brake member 10 via an intermediate lever 21.
In particular, as shown in FIG.
is a three-armed angle lever, and the angle lever is pivotable about a shaft 22 fixed to the casing. The first arm 23 facing upward in FIG. 2 is located near the outer edge of the other end 26 of the brake spring 11.
The second arm 25 has a hooking groove 24 and is somewhat longer than the downwardly directed second arm 25, into which the other end 28 of the brake band 12 is hooked. The third arm 27 of the lever-shaped brake member 10 is connected to the other two arms 23,
25, and is located approximately half the length between both arms. The intermediate lever 21 is pivotally attached to the free end of the third arm 27. The free end 30 of the intermediate lever 21 has a partially circular locking opening 31 whose one limiting wall 33 merges into a flat outer surface 33 a of a finger-shaped projection 34 . Locking port 31 and outer surface 33
a is adapted to the shape of the rounded chamfered end 35 of the associated locking member 20, and the locking opening 3
1 fits over the end portion 35 of the locking member 20, and the outer surface 33a of the finger-shaped protrusion 34 covers the entire surface of the locking member 20.
It is adapted to come into contact with the longitudinal edge 36 of the first arm 37 of. The locking member 20 is configured as a two-armed lever, and the first arm 37 and second arm 37a, which are configured in a substantially slender rectangular shape with substantially the same length, form a large obtuse angle with each other. are doing. The locking element 20 is preferably mounted on the housing 16 of the power chain saw 1 so as to be pivotable about an axis 38 in the direction of the arrow P shown in FIG. 2 by means of a double leg spring 39. Said double-legged spring 39 is supported at one end 39a in the area of the pivot axis 38 on the end 35 of the locking member 20, and at the other end 41 is also supported on the casing 16 (first
(Fig.) is fixed. The free end 32 of the second arm 37a of the locking member 20 is the end 3 of the first arm 37.
5, the free end 32, when coming into contact with the driver 19, comes into contact with the driver 19 essentially only in a line contact and therefore without any force. The end 35 of the locking element 20 has a locking pin 35a with a midpoint M, which projects beyond the outer surface 45a facing the casing (FIG. 2b).

The actuating member 8 is configured as a one-arm pivot lever, one end 44 of which engages a Bowden operating cable 7 connected to the pressure member 6 (FIG. 1). There is. However, the actuating member may also be released by an electric, pneumatic or hydraulic device, which device is in this case connected to a sensor, switch or similar release element.
The actuating member 8 is attached to the casing 16 so as to be pivotable about an axis 46 (FIG. 2a), and on the side of the casing 16 that is remote from the attachment point, the locking pin 35a of the locking member 20 is attached to the casing 16. The support plate 47 is formed as a claw-shaped support plate 47, which is partially curved in a circular shape with the axis 46 (FIG. 2a) as the center of curvature. Actuation member 8
is eccentrically supported such that the line of action of the contact force F of the locking pin 35a at the contact portion 50 with the support plate 47 has a lever arm with respect to the shaft 46.

In the ready position shown in FIG. 2 of the chain brake device 9, the brake spring 11 is connected to the brake member 10.
Brake band 1
2 is in a state separated from the brake drum 13. The brake member 10 includes a locking member 20,
It is held in a ready position by a locking mechanism consisting of an intermediate lever 21 and an actuating member 8, in which the intermediate lever 21 connected to the brake member 10 can be moved beyond the extended position by the working member 8. Being pressed. The locking member 20 and the intermediate lever 21 are held in this state by the actuating member 8. The shaft 29 of the brake member 10 and the shaft 38 of the locking member 20 are located on the right side (as viewed in FIG. 2) from the midpoint of the knitting joint 48 formed by the locking pin 35a and the locking port 31. It is located on a straight line G extending at a slight interval. In this position, the knitting joint 48 is subjected to a leftward force by the brake spring 11 that tends to rotate the knitting member 20 in the direction opposite to the arrow P. However, the rotation of the locking member at the knitting joint 48 is prevented by the support plate 47 of the actuating member 8 supporting the locking pin 35a of the first arm 37 of the locking member 20 on the side. The knitting joint 48 is therefore in a fixed position. The actuating member 8 itself is configured such that when subjected to the force of the locking member 20, it rotates to release the locking member. The bearing plate 47 is subjected to an opening moment by the knitting joint 48 via the locking pin 35a. In particular, the shaft 46 of the bearing plate 47 is located below the contact portion 50 with the locking pin 35a (FIG. 2a), thereby pivoting the actuating member 8 to the open position shown in FIG. A moment is generated. What is important here is that the support plate 4 of the actuating member 8
The only thing to do is to make the trigger release force acting on the trigger 7 as small as possible.

The pivoting movement of the actuating member 8 is prevented by a trigger or a reaction force acting on the actuating member 6, which reaction force is caused, for example, by the hand (not shown) of the operator of the power chainsaw 1 gripping the throttle lever. It is generated accordingly. When the operator releases the rear grip 4, for example in the event of a fall, the slack in the Bowden operating cable 7 eliminates the reaction force that fixes the position of the actuating member 8, and the actuating member acts on it. It is rotated by the opening moment.

When the actuating member 8 pivots downward, the support plate 47 also moves accordingly, so that the contact area 50 of the support plate 47 with the locking pin 35a of the locking member 20 reaches below the lower edge 51 of the locking pin 35a. downward movement;
This releases the locking member 20 (FIG. 3). At the same time, the locking member 20 receives the force of the intermediate lever 21 and moves in the opposite direction to the direction of the arrow P, in other words, toward the left as seen in FIG. 3 against the spring force acting on the locking member. do.

In this position, the knitting joint 48 formed between the locking member 20 and the intermediate lever 21 in the ready position of the chain brake inner 9 no longer transmits a holding force to the brake member 10 and the intermediate lever 21
is forced out of the knitting joint 48 via the contact edges 49 of the finger-shaped projections 34 (FIG. 3).
In this case, the contact edge 49 is supported on the longitudinal edge 36 of the first arm 37 of the locking member 20.

The finger-shaped projection 34 thereby causes the knitting joint 48 to be released quickly after the release of the actuating member 8 at the beginning of the braking operation. In that case, the rake element 10 can no longer be held in its ready position by the locking devices 8, 20, 21 against the force of the brake spring 11, so that the brake element 10 absorbs the spring action of the brake spring. Accept, 4th
It is swiveled to the braking position shown in the figure. At the same time, the brake band 12 is pulled toward the right until it comes into tight contact with the circumferential surface of the brake drum 13 and immediately brakes the brake drum. In conjunction with the braking of the brake drum 13, the saw chain (not shown) is stopped, so that the risk of injury due to contact with or entanglement with the circulating saw chain is largely avoided.

The swinging member 20 pivots about the shaft 38 in the direction of the arrow P under the force of the double leg spring 39, thereby attempting to enter the rotational track 52 of the entrainer 19. However, this pivoting movement causes the pivoting member 20 to move to the second contact area 53 of the bearing plate 47, which is located opposite the aforementioned first contact area 50.
(Figure 4).
Accordingly, both contact areas 50 and 53 of the support plate 47 form contact surfaces for the locking pin 35a, so that the knitting joint 48 opens toward the left hand and the locking member 20 is rotated by the cam. Situations such as intrusion into the orbit are prevented.

In the abutting or locking position shown in Figure 4,
The second arm 37a of the locking member 20 is the entrainer 19
Since it is held in the outer area of the rotating orbit 52 of
The chain brake device 9 cannot be brought into its ready position undesirably. In this abutting position, the power chain saw 1 is effectively braked, with the engine rotating at a speed below the slip speed of the clutch.

In order to separate or release the brake band 12 from the brake drum 13, the locking action between the actuating member 8 and the locking member 20 must first be released. This is because only after this locking effect is removed can the locking element, under the action of its spring force, be able to penetrate into the rotational track 52 of the driver 19. For this purpose, the trigger or pressure member 6 is pressed by gripping the rear grip 4, as a result of which the actuating member 8 is pivoted upwards about the pivot axis 46 (FIG. 5). At the same time, the second contact portion 53 of the support plate 47 moves clockwise, and the locking pin 35a is moved against the Kotsukin member 2.
Under the action of the spring force of the two-legged spring 39, the second arm 37a of the locking member 20 pivots into the rotational track 52 of the entrainer 19 at an arbitrary position. Next, tightening member 20
follows the entrainer 19. Contact surface 55 between the entrainer 19 and the second arm 37a of the locking member 20
As the distance from the entrainer axis 56 decreases,
At the same time as the first arm 37 of the locking member 20 moves toward the right hand, the end 3 of the locking member 20 moves toward the right hand.
5 presses the intermediate lever 21 laterally, so that the intermediate lever pivots towards the right hand (FIG. 5) and the finger-shaped projection 34 of the intermediate lever is pressed against the pressure spring 54 fixed to the casing 16. Contact. This causes the intermediate lever 21 to press against the pressing spring 5.
4 and is loaded in the direction of arrow P'.
The cocking member 20 has a cam base circle 57 limited by the minimum distance of the contact surface from the entrainer shaft 56.
Just before reaching (FIG. 6), it snaps by means of its end 35 into the associated locking opening 31 of the intermediate lever 21 (FIG. 7). The end 35 of the locking member 20 is pivoted by the driver 19 toward the left in a direction opposite to the direction of the arrow P and comes into contact with the outer surface 33a of the intermediate lever 21. As a result, with further rotation of the driver 19, the locking member 20 and the intermediate lever 21 form a common knitting joint 48. The knitting joint 48 can only transmit forces in a specific direction, namely towards the axis 29 of the brake element 10. Taken child 19
When the brake member 10 rotates further, the brake member 10 is lifted and the brake spring 11 is compressed. In this locking position, the brake member 10, the locking member 20, and the intermediate lever 21 form one quadrilateral link mechanism, and in this case, just before the second arm 37a of the locking member 20 contacts the apex 59 of the entrainer 19 (the (FIG. 8) The locking member 20, together with the intermediate lever 21, assumes a straight extended position.
The vertex 59 having the maximum distance from the entrainer axis 56
When the locking member 20 reaches, the intermediate lever 2
1 is pressed beyond the extended position. Upon overcoming this extended position, the forces acting on the tucking member 20 are also deflected, so that the free end 32 of the tucking member is automatically pushed out of the rotational path 52 of the entrainer 19 (FIG. 2) and The locking member 20 is restricted from further movement by the actuating member 8. In order to avoid uncontrollable friction between the entrainer 19 and the pulling member 20, the free end 32 of the entraining member 20 or the entrainer 19 is provided with a sliding bearing or It is also possible to arrange rollers (not shown) with rolling bearings.

In order to release the brake band 12 from the brake drum 13, only the trigger or actuating member 8 needs to be operated, so the release operation does not require a high force and can be performed easily and quickly. Since both hands can remain on the front support grip 2 and the rear grip 4 of the power chainsaw 1, the power chainsaw is also ready for use. If the front support grip 2 is also provided with a trigger, it is possible to obtain the desired two-handed protection.

The chain brake device 9 of the present invention has the advantage that even if the device has a high frequency of erroneous trigger operations, the operator will not be burdened more than expected due to the erroneous trigger operations. This is because the chain brake device according to the invention can be returned to the brake release or braking position in a very short time and with little effort by simply actuating the trigger.

The chain brake device of the present invention described above can particularly easily and quickly release the braking operation. That is formation joint 4
8 is fixed in position by the actuating member 8 just before reaching the extended position (FIG. 2).
As a result, the knitting joint 48 is only slightly displaced, so that the supporting force acting on it is small and the operating force is correspondingly small.

The simple and quick operation of the chain brake device 9 provides the prerequisites for the use of as many danger signals as possible in addition to the prerequisites for pure reaction braking. For example, it is also possible to connect the throttle lever 5 and/or the arcuate protection member 18 for hand protection to the actuating member 8.

In any case, it is only necessary to connect the actuating member 8 with a danger signal generator which serves as a trigger, the trigger being e.g. It is possible to configure it by means of another signal generator arranged. Additionally, it is also possible to provide such a signal generator in the front support grip as a two-handed protection device. In that case, it is always possible to easily and quickly release the brake body 12 by operating each trigger portion. Other danger signals significantly reduce injuries caused by the chain during coasting, injuries caused by being caught in the circulating chain, and injuries caused by brake failure when starting the power chainsaw. The chain brake device 9 of the present invention is also lightweight in terms of weight. This is because the brake device is
This is because it consists of a small number of simple parts such as a brake lever, an intermediate lever, a locking lever, and an operating lever.

When the bow-shaped disaster prevention material for hand protection is connected to the actuating member for release, the chain brake device is automatically released when the bow-shaped disaster prevention material recoils, so that the automatic reaction braking device is activated. obtained (Figure 9).

In the chain brake device 9' shown in FIG.
The hand protection arc 18' engages via a driver 18a in a switching unit 60, which essentially consists of a disc 61 which is rotatably held in the casing. The disk 6
1 is spring-loaded counterclockwise by a tension spring 62 fixed to the casing. A Bowden operating cable 7' is engaged as a tension link with the disk 61, and one end 63 of the operating cable is movable within a guide hole (not shown) of a stopper 65. The stopper 65 projects perpendicularly above the outer surface 64 of the associated disk;
For example, it is configured in a web shape. The end 63 of the Bowden operating cable 7' is configured as a nipple, so that when the pressure member 6' fixed to the other end 66 of the Bowden operating cable 7' is released, the Bowden operating cable 7' The nipple abuts against the stopper 65. The pressure member 6' is
As in the first embodiment shown in FIGS. 1 to 8, it is pivotable and spring-loaded in the opposite direction to the pressing direction P'' into the rear grip (not shown) of the power chainsaw. is supported by.

Further, a lever-like actuating member 8' is engaged with the disk 60 via a rod 67, and the rod has one end 68 that is connected to the rotation shaft 69 of the disk 60.
The disc is pivotably mounted above the disc and spaced to the right from the rotation axis. The other end 70 of the rod 67 is pivotally connected to an actuating member 8', which is arranged in the casing so as to be pivotable about a pivot axis 46'.

In the illustrated ready position, the upper end 35' of the lever-like actuating member 20' is moved by the roller 71 mounted on the pin 35'a into the first contact area 50 of the bearing plate 47' of the lever-like actuating member 8'. ' is in contact with . The first contact region 50' is formed by the upper section of the opening edge 47'a, whose center of curvature is the pivot axis 46' of the lever-like actuating member 8'.
The roller 71 is in line contact at the first contact portion 50';
Therefore, contact occurs with only a slight surface pressure. Since the rolling friction of the roller 71 on the actuating member 8' is minute, the actuating member can be easily and quickly moved to the braking position with a small amount of labor input.

Bow-shaped disaster prevention material 18' during recoil of power chainsaw
is released, the disc 61 is released
a in the clockwise direction (in the direction of the arrow P'') against the force of the tension spring 62. This rotation is caused by the free movement section of the nipple of the Bowden operating cable, causing the pressure member to 6' is also possible, in which case the rod 67 moves downwards, whereby the actuating member 8' pivots upwards about the pivot axis 46' in the direction of the arrow P''''. At that time, roller 7
1 slides downwardly along the opening edge 47'a into the bottom 73 of the bearing plate 47'. At the same time, the knitting joint 48' is also separated and the roller 71 is fixed in position on the opposing second contact area 53' of the bearing plate 47', so that the knitting member 20' cannot enter into the cam rotation path. The second contact portion 53', like the first contact portion 50', is curved with the pivot axis 46' of the actuating member 8' as the center of curvature.

In order to release the brake band, first the arcuate protection member 18' for hand protection is brought back into its ready position, then the pressure element 6' is swiveled from its unswiveled, unpressed position into the shown pressed position. As a result, the disk 60' is rotated counterclockwise under the spring force of the tension spring 62. As a result, the actuating member 8' is pivoted downward in a clockwise direction via the rod 67. At the same time, the kneading member 2
0' roller 71 moves upwardly beyond the second contact point 53'. At that time, the locking member 2
With the pin 35'a supporting the roller 71, the locking member 20 is slid along the opening edge 74 which is retracted in the direction of the casing relative to the second contact portion 53'. ' transforms the contact surface on the actuating member 8'. Due to this, the locking member 2 when entering the cam rotation orbit
0' reciprocation is avoided. This is because switching takes place over the shortest possible distance. Thus, as already mentioned, the locking member 20'
enters the cam rotation orbit. The cocking member 20' is then pivoted by the force of the contacted cam, engages with the intermediate member 21' as shown in FIGS. 6 and 7, and then moves toward the left until it passes the starting position. Move to the ready position shown;
It is fixed in this position by the actuating member 8'.

The chain brake device 9' can also be released by releasing the pressure member 6' during operation. In this case, by means of a pressure spring 75 or via a Bowden actuating cable 7' or a stopper 6.
5 through the nipple 63 in contact with the disk 60.
is rotated clockwise (in the direction of arrow ``P''), and at the same time, the actuating member 8' is rotated upward in the direction of arrow P''.This causes the roller 71 of the locking member 20' to move against the support plate 47. ', so that the knitting joint 48 is released and the brake member 1
0' is pivoted to bring the brake band 12' into contact with the brake drum under the spring action of a brake spring 11' connected to the brake member. In order to release the brake band 12', the pressure element 6' must be pressed again as described above.

10, 11 and 12 show another embodiment of a power chainsaw 1b equipped with a chain brake device 9b of the present invention. Parts corresponding to the chainsaw described above are indicated by the same reference numerals plus the symbol b. The chain brake device 9b of this embodiment includes an actuation member 8b, a trigger,
In other words, the only difference from the embodiment shown in FIG. 9 is the configuration of the arcuate disaster prevention material 18b for protecting the hands.

The actuating member 8b is constituted by a plate-shaped two-armed swing lever, and the swing lever is pivotable about the swing shaft 46b.
b, and two lever arms 51b and 51
b'. Lever arm 51b of actuating member 8b
A Bowden type operating cable 7b is engaged in the free end of the . One end 58b of the Bowden type operating cable is hooked into a guide slot 43b of the lever arm 51b, which is partially curved into a circular shape with the pivot axis 46b as the center of curvature.

The other lever arm 51b' of the actuating member 8b has a bearing opening 47b with a first wall section 47b' and a second wall section 47b''. Said second wall section 47
b'' is curved around a center of curvature M located at a distance 1 from the pivot axis 46b.The lever arm 51b' is bent at a substantially right angle at its free end 51b''.

A web 100b located approximately at the level of the pivot shaft 46b is provided between the support opening 47b and the adjacent notch 40b which is opened in a substantially V-shape (FIGS. 11 and 12). , the lower surface of the web forms the aforementioned first wall section 47b'. The end surface 50b of the web 100b forms a first contact site for the end 35b of the locking member 20b. The end face is the pivot axis 4 of the actuating member 8b.
It is curved with 6b as the center of curvature. The locking member 20b also has a roller 71b supported by a pin (not shown) on the end portion 35b.
Chain brake device 9 shown in Figures and Figure 11
The arcuate disaster prevention material 18b for hand protection, which forms the first trigger for b, contacts the first contact portion 50b in the ready position.

The edge section of the recess 40b close to the guide slot 43b particularly advantageously has a vertically outwardly projecting stopper piece 42b, on which a driver 67b of the arcuate protection element 18b for hand protection is fitted. Make contact in the ready position. The entrainer 67b is the first arm of the tri-arm-shaped end 18b' of the arch-shaped disaster prevention material 18b for protecting the hands, which is formed in a substantially star shape. The entrainer 67b is attached to the other second and third arms 101b, 10 of the tri-armed end 18b'.
2b and tapers toward a free end 67b', which is connected to the notch 4.
Thinner than 0b.

The second bay 101b of the tri-armed end 18b' is pivotally connected to a joint arm 103b which is pivotally connected to the casing 16b to form a toggle joint. By means of the toggle joints 101b and 103b, the bow-shaped disaster prevention material 18b for hand protection is preloaded via the pressure spring 62b both in the ready position (Figs. 10 and 11) and in the release position (Fig. 12). ing. This is because in both of the above positions, the pivot point G is at the joint arm 1, as is clear from FIGS. 11 and 12.
Line of action of the force of the pressure spring 62b that engages with 03b
This is because they are located to the left and right of Wb.

The third end of the end 18b' of the arcuate disaster prevention material 18b for protecting hands.
The arm 102b is connected to the bow-shaped disaster prevention material 18b like the other arms.
It is configured to taper outward from the pivot axis 69b. The third arm is used as a driver for the brake member 10b, and when the arcuate safety member 18b pivots from the release position (Fig. 12) beyond the ready position (Fig. 11) and returns in the direction of arrow P'. The third arm 102b contacts the brake member 10b. The brake member 10b is then pivoted slightly clockwise, so that the brake band 12b is spaced apart from the brake drum 13b (FIG. 10) by some distance.
This function is also possible when the brake is released via the pressure member 6b. However, in this case, the hand-protecting arcuate member remains in its ready position. If the occurrence of wear is relatively high, the saw chain (not shown) and the chain wheel (also not shown) of the power chain saw 1b can be quickly and conveniently retensioned and replaced in this spaced position of the brake band 12b. It is. This operation can be performed when the power chainsaw is stopped and the brake is released.

When the bow-shaped disaster prevention material 18b for hand protection is released during the recoil of the power chainsaw, the bow-shaped disaster prevention material resists the force of the pressing spring 62b in the clockwise direction (the 11th direction).
This turning movement is transmitted to the actuating member 8b via the entrainer 67b, and at the time of this transmission, the entrainer contacts the stopper piece 42b, thereby rotating the actuating member 8b. The actuating member 8b is rotated in a counterclockwise direction about its pivot axis 46b.
This is made possible by the free movement section within 3b. At the release position of the bow-shaped disaster prevention material 18b for hand protection, the end portion 58b of the Bowden type operating cable is connected to the guide slot 43b when viewed in the direction of rotation of the actuating member 8b.
The free end 67b' of the driver 67b is located in the cutout 40b (FIG. 12), whereas it contacts the rear end. When the actuating member 8b is pivoted, the roller 71b of the locking member 20b moves against the first wall section 47.
b' and slide downward to open the bearing opening 4.
The second wall section 47b'' of 7b is reached. In this case also the knitting joint 48b is released (FIG. 12) and, since it is no longer supported on the actuating member 8b or on its web 100b, the knitting joint 48b moves towards the left. The opening moment caused by the overtensioned knitting joint can act effectively.The roller 71b is then fixed in position in the bearing opening 47b, so that the locking element 20b can move against the driver 19b. Rotating orbit 52b (first
Figure 0) cannot be penetrated.

The twisting member 20b is loaded in the direction of arrow P (FIG. 12) by a torsion spring (not shown) engaged therewith, and the center of curvature M of the second wall section 47b'' is Actuation member 8b
Since the actuating member 8b is located at a distance of 1 from the pivot axis 46b, a clockwise torque acts on the actuating member 8b. When the pressure member 6b is in the pressed position by the release of the chain brake device 9b, the actuating member 8b is prevented from rotating by the free end 67b' as a trigger arm.
Due to the free movement section of the end 58b of the Bowden operating cable 7b in the guide slot 43b, the first
It can be freely rotated clockwise to the position shown in Figure 1. If, on the other hand, the pressure member 6b is released, the free end 58b of the Bowden operating cable 7b abuts against the end in the region of the guide slot 43b, so that the actuating member 8b is additionally rotated. be prevented. Therefore, in order to release the brake, the pressure member 6b must be in a pressed state or be pressed, in which case the end 58b of the operating cable is connected to the guide slot 43.
As the actuating member 8b moves upwardly within the Bowden operating cable 7b, a void is created below the end portion 58b of the Bowden type operation cable 7b, and due to the void, the actuating member 8b receives the force of the swinging member 20b and undergoes a turning movement. becomes possible.

This return of the actuating member 8b is possible only if the arcuate disaster prevention material 18b for hand protection is previously turned by hand to its ready position (FIG. 11), and in this preparation position, the arcuate disaster prevention material 18b is rotated by hand in advance. is toggle lever 10
1b and 103b, it is automatically locked at the release position.

When the actuating member 8b pivots from the release position to the ready position, the roller 71 of the locking member 20b
b slides through the second wall section 47b'' into the bent free end 51b'' of the lever arm 51b' of the actuating member 8b. The locking member 20b can now be rotated in the clockwise direction by the spring action of the torsion spring engaged therewith. The free end 32b of the second arm 37b' of the locking member then enters into the rotational track 52b of the driver 19b. As a result, the cocking member 20b comes into contact with the entrainer 19b and follows the movement of the entrainer. As the distance between the contact surface between the entrainer 19b and the second arm 37b' of the cocking member and the entrainer axis decreases,
The first arm 37b of the locking member 20b moves in the clockwise direction and the locking member also pushes the intermediate lever 21b laterally with the end 35b of the first arm, so that the intermediate lever pivots in the counterclockwise direction. and the free end 34b of the intermediate lever is fixed to the casing by a pressing spring 54b (FIG. 10).
come into contact with. As a result, the intermediate lever 21b is spring-loaded towards the locking member 20b. Just before reaching the cam base circle 57b limited by the minimum distance between the contact surface and the entrainer shaft, the end 35b of the first arm 37b of the cocking member 20b
snaps into the associated locking opening 31b (FIG. 12) of the intermediate lever 21b, thereby forming a knitting joint 48b. The knitting joint can only transmit force in a specific direction, that is, in a direction toward the pulling member 20b. When the entrainer 19b further rotates, the brake member 10b
is pivoted in a clockwise direction about axis 22b, and then brake spring 11b is tensioned, ie, cocked. Lever 10b, 20b, 2
1b forms a quadrilateral linkage in this locking position (FIG. 11), in which case the second arm 37b' of the locking member 20b and the entrainer 19b'
Immediately before contacting the apex 59b (Fig. 10) of 9b,
The locking member 20b occupies the extended position together with the intermediate lever 21b. When reaching the apex 59b having the maximum distance from the pivot axis of the entrainer 19b, the intermediate lever 21b is pushed to the left beyond the extended position of FIG. Once the extended position is overcome, the torsion spring force engaging the cocking member 20b is also deflected, so that the cocking member automatically moves the entrainer 1
9b is pushed out of the rotating orbit 52b and is restricted from further movement by contacting the web 100b of the actuating member 18b.

The chain brake device 9b can also be released by releasing the pressure member 6b during operation of the power chainsaw. In this case, the end 58b of the Bowden operating cable 7b is moved downwards, and the actuating member 8b is then rotated counterclockwise. As a result, the roller 7 of the locking member
1b moves into the bearing opening 47b, the knitting joint 48b dissociates, and the brake member 10b
is a brake spring 11b that engages with the brake member.
The brake band 12b is rotated so as to come into contact with the brake drum 13b under the force of the spring. In order to release the brake band, the pressure member 6b must be pressed again, but in this case the end 58b of the Bowden operating cable 7b is inserted into the guide slot 43.
b, and at the same time the actuating member 8
b is a locking member 20 that engages with the actuating member;
b is rotated in a clockwise direction into the ready position in FIG.

This chain brake device has an extremely simple structure, and therefore can be manufactured at an extremely low cost and has an extremely low failure rate.

The particular difference between the embodiment shown in FIGS. 13 to 16 and the embodiments already described is that the end 58c of the Bowden type operating cable 7c is
is hooked on an approximately partially circular switching element 72c, which is particularly advantageously made of sheet metal and cooperates with the actuating element 8c. Furthermore, Figures 10 to 12
A toggle lever 101 that locks the bow-shaped disaster prevention material 18b for hand protection shown in the figure in the ready position and the braking position.
b, 103b is omitted. Instead, only a pressure spring 105c fixed to the casing 16c is provided, which pressure spring is connected to the second arm 10.
1c is pressed, so the bow-shaped disaster prevention material 18c for hand protection is pressed.
is held in its ready position (FIGS. 13 and 15) and preloaded toward this ready position, so that the arcuate disaster prevention member
c, it is automatically swung back from the braking position (FIG. 14) to the ready position.

The operating member 8c is different from the operating member 8b shown in FIGS. 10 to 12 in that it does not have a slot, and the pivot axis 46c of the lever arm 51c closer to the Bowden type operation cable 7c is curved. The centrally curved outer edge 74c has two (first and second) stepped portions 104c and 76c spaced apart from each other in the circumferential direction. A second stopper piece 77c located substantially perpendicular to the stopper piece 42c disposed at the free end 67c' of the entrainer 67c of the bow-shaped disaster prevention member 18c is disposed on the first wide stepped portion 104c. It is set up. The second stopper piece 42c is formed by the free end of the switching member 72c remote from the Bowden operating cable 7c. In its ready position, the actuating member 8c is in contact with the second stopper piece 77c with the first step 104c (FIG. 13). The second step 76c is used as a locking port, and when the actuating member 8c is in the braking position (FIG. 15), a leaf spring 78c fixed to the casing is preloaded toward the actuating member 8c. The free end portion of the second step portion 76c engages with the locking opening of the second step portion 76c. This causes the actuating member 8c to be acted upon by the locking member 20c, which then presses the lever arm 51c' of the actuating member 8c with its roller 71c (FIG. 15). - a rotation back to the ready position in the chronological direction is prevented.

The second stopper piece 77c has the role of interlocking the actuating member 8c to its release position when the pressure member 6c is released, and the role of releasing the engagement of the leaf spring 78c. For this purpose, the second stopper piece 7
7c is configured to have a length that extends outward relatively widely beyond the width of the first step portion 104c to which it belongs. The distance between the first step portion 104c and the second step portion 76c is such that the second stopper piece 77c
When the overhanging edge 79c (FIGS. 10 and 16) exceeding 04c is pressed against the leaf spring 78c and the pressing member 6c is released (FIG. 16), the switching member 72c turns counterclockwise. The leaf spring is selected so as to prevent the actuating member 8c from moving in the same direction via the second stopper piece 77c.

When the bow-shaped disaster prevention material for hand protection 18c is turned in the direction of the arrow P shown in FIG.
The free end 67c' of the first stopper piece 42c
and by further pivoting, the actuating member 8c
is interlocked to the braking position shown in FIG. In this case, the leaf spring 78c is located in the edge section 80c (FIG. 13) furthest from the Bowden operating cable 7c.
along the second step 76c until it comes into contact with the associated edge section 81c at the rear of the second step 76c, viewed in the direction of rotation (FIG. 14). As explained based on FIGS. 10 to 12, the locking member 20c is disengaged from the intermediate lever 21c, and the roller 7 of the locking member 20c is disengaged from the intermediate lever 21c.
1c slides into the bearing opening 47c. The arcuate disaster prevention material 18c for hand protection automatically returns to the ready position and pivots under the spring force of the pressure spring 105c that presses the second arm 101c. In this case, the child 67c
is released from the first stopper piece 42c. The actuating member 8c receives the action of the cocking member 20c,
The leaf spring 78c is rotated clockwise until the free end of the leaf spring 78c comes into engagement contact with the second step 76c of the actuating member 8c (FIG. 15). Second stopper piece 77c
is located at a distance from the first step portion 104c at this locking position. This is because the switching member 72c does not rotate in conjunction with the release by the arcuate disaster prevention member 18c for protecting the hand.

From the locking position, the actuating member 8c moves to the pressing member 6c.
It is possible to return to the ready position only by actuation of . For this return, first the actuating member 6
c must be released (FIG. 16), which causes the switching member 72c to slide counterclockwise along the outer edge 74c and push the leaf spring 78c into the second stop with the overhanging edge 79c of the second stopper piece 77c. It is pushed out from the second stage portion 76c.

Thereby, the actuating member 8c is activated by the locking member 2.
0c, the first step portion 104c can rotate clockwise until it comes into contact with the second stopper piece 77c of the switching member 72c (FIG. 16). In this resting position, the free end of leaf spring 78c rests against edge section 80c of actuating member 8c. In order to bring the actuating member 8c from this position into the ready position, the pressure member 6c must be pressed again, which causes the switching member 72c to be moved clockwise via the Bowden actuating cable 7c into the thirteenth position. Swivel to the position shown, thereby opening the actuating member 8c. The actuating member 8c is now again under the action of the locking member 20c and can be rotated further in the clockwise direction until it abuts the second stopper piece 77c (FIG. 13).

During this rotation of the actuating member 8c, the locking member 2
As explained in connection with the previous embodiment, the 0c roller 71c extends into the region of the bent free end 51c'' of the lever arm 51c' of the actuating member 8c, so that the lever arm 37c' of the cocking member 20c enters the cam rotation path of the driver, thereby realigning the knitting joint 48c (FIG. 13) and retensioning the brake member 10c.

The advantage of this embodiment is that the bow-shaped disaster prevention material 18c for hand protection is
Since it is automatically returned via the pressure spring 105c, it is no longer necessary to return it by hand, and the operation of the power chainsaw becomes extremely simple.

In the power chainsaw shown in FIGS. 13 to 16, it is also possible to release the chain brake by operating the pressure member 6c. When the pressure member 6c is released, it pivots counterclockwise under the action of the spring, and then
The actuating member 8c is interlocked and rotated counterclockwise by the switching member 72c via the abutting connection between the second stopper piece 77c and the first step portion 104c. The roller 71c of the locking element 20c thereby pivots into the bearing opening 47c of the actuating element 8c, so that the knitting joint 48c is released;
The brake member 10c is pivoted to the braking position by the spring force of the brake spring 11c. As a result, the brake band 12c is connected to the brake drum 13c (first
(Figure 0) is crimped. In order to release the chain brake, it is necessary to press the pressure member 6c, as described above. In this embodiment, if a further inertial mass is provided for releasing the chain brake, which is operatively connected to the actuating member in the manner already described, the arcuate protection material for hand protection is arranged immovably. It is also possible to do so.

As shown in FIG. 17, the pressure member 6d can be operatively connected to the throttle lever 5d via a double leg spring 82d. A double leg spring 82d surrounds the shaft 83d of the throttle lever 5d, and one spring leg piece 84d also supports the throttle lever 5d.
is pressed outward from the lower surface of the rear grip 4d, while the other spring leg piece 85d protrudes into the slit in the end wall 86d of the pressing member 6d when the pressing member 6d is not pressed. ing. Pressing spring 8
When the pressure member 6d is pushed down and the throttle lever 5d is pushed up against the spring force 9d, the free end 87d of the spring leg 85d is locked in the corresponding locking hole 88d in the end wall 86d. There is.

Even if the pressure member 6d is released in this throttle fully open position of the throttle lever 5d, the pressure member cannot return to its starting position and pivot due to the spring force of the pressure spring 89d. This is because the pressure member is locked by the spring leg 85d. This prevents the chain brake from being released with the throttle fully open. Rather, a chain brake can only be released after the rotational speed has decreased. For braking, the throttle lever 5d must first be released in order to move the pressure member 6d into the release position shown in FIG. 17 in any case. When the throttle lever 5d returns, the spring leg piece 85d is pushed out from the locking opening 88d, and the pressure member 6d is released. The chain brake device is then released as described above.

This arrangement ensures that the chain brake device cannot be released in the fully open throttle position.

In the embodiment shown in FIGS. 19 and 20, the pressure member 6e is arranged coaxially adjacent to the throttle lever 5e, so that the pressure member 6e projects downward from the lower surface of the rear grip 4e. ing. As a result, the pressure member 6e and the throttle lever 5e are simultaneously wrapped by three fingers 90e and one finger 90e' of one hand of the operator. In that case, it goes without saying that the finger 90e' is the finger that is applied to the throttle lever 5e. When the pressure element 6e is removed, the throttle lever 5e is generally opened so that the gas is withdrawn and the brake is therefore released only at low rotational speeds.

In this embodiment, it is possible to provide a locking mechanism having a double leg spring between the pressure member 6e and the throttle lever 5e, corresponding to the embodiments shown in FIGS. 17 and 18. .

In the alternative embodiment shown in FIGS. 21 and 22, no special pressure member is provided, so that the chain brake device must be released with the throttle lever 5f. The throttle lever is
It cooperates with a hook-like intermediate member 6f arranged inside the rear grip 4f.

The hook-like intermediate member 6f is connected to the rear grip 4 at a pivot end 92f that is remote from the hook end 91f.
It is pivoted to f. A Bowden type operating cable 7f is attached to a pivot point 93f located approximately half the length of the hook-like intermediate member 6f. The pressing spring 9 is inserted between the pivot point 93f and the pivot end 92f.
4f engages the hook-shaped intermediate member 6f, and the pressure spring holds the hook-shaped intermediate member in the starting position shown in FIG.

The throttle lever 5f is at the braking position (the position shown in FIG. 21 and the position shown by the broken line in FIG. 22) and the second position.
The throttle lever link 95f is hooked into the elongated slot 96f of the throttle lever 5f so that it can move freely relative to the throttle lever link 95f between the no-load operating position shown by the solid line in FIG. It is rare. When the throttle lever 5f is pressed, the throttle lever link 95f is actuated only after it has overcome the free movement section in the elongated slot 96f. As shown in FIGS. 21 and 22, between the braking position and the no-load operating position of the throttle lever 5f (FIG. 21), the hook-shaped intermediate member 6f is connected to the first and second positions of the throttle lever 5f. Step 9 between second partially circular curved edge sections 98f, 99f
7f at the hook end 91f. The second curved edge section 99f has a significantly larger radius of curvature than the first curved edge section 98f.

When the throttle lever 5f is pivoted beyond the no-load operating position shown in FIG. 22 into the fully open throttle position, the hook-shaped intermediate member 6f contacts the second curved edge section 99f. Hook-shaped intermediate member 6f
is supported on the second curved edge section 99f, the hook-like intermediate member
It will not turn even if you activate it. That is the second
This is because the center of curvature of the curved edge section 99f is the pivot axis of the throttle lever 5f. Therefore, since no shift force acts on the Bowden type operating cable 7f, the chain brake device is not operated. The chain brake device is released and the brake drum is braked only when the throttle lever 5f is pivoted from the no-load operating position (FIG. 22) to the braking position (FIG. 21). This is because in this case, when the hook end 91f of the hook-like intermediate member 6f is directed toward one side, the stepped portion 97f
This is because the vehicle is rotated in accordance with the width of the vehicle. Therefore, in order to release the brake of the power chainsaw, the throttle lever 5f must be moved to the no-load operating position (22nd position).
(Fig.). Based on this configuration, it is also ensured in this embodiment that the brake is released only at low rotational speeds, and that it is not released at the fully open throttle position. This release operation is performed in the same manner as in the embodiments shown in FIGS. 17 to 20, which have already been described.

[Brief explanation of the drawing]

FIG. 1 is a side view of a power chainsaw showing the chain brake device of the present invention in a ready position with the side wall partially split and the trigger activated; FIG. 2 is a side view of the chain brake device shown in FIG. 1; Figure 2a is a side view of the locking mechanism portion of the chain brake device in Figure 2 with the locking member of the locking member omitted, Figure 2b is the arrow b in Figure 2.
3 is an enlarged side view of the chain braking device of FIG. 2 shown in the intermediate position with the trigger in the actuated state, and FIG. 4 is the braking position. 5 is an enlarged view of the chain brake device shown with the locking member held in the locked position outside the rotational orbit of the entrainer of the chain brake device, and FIG. FIG. 6 is a side view of the chain brake device showing the locking member that has been moved, and FIG. 6 is a side view of the chain brake device shown in FIG. 7 is a side view of the chain brake device shown in FIG. 6 showing the locking member and the brake member forming one knitting joint; FIG. 8 is a side view of the chain brake device shown in FIG. FIG. 7 is a side view of the chain brake device shown in the immediately extended state; FIG. 9 is a schematic side view of the chain brake device according to the second embodiment of the invention in the ready position; and FIG. 10 is the side wall partially shown. 11 is an enlarged side view of the chain brake device shown in FIG. 10, and FIG. Fig. 12 is a side view of the chain brake device of Fig. 11 shown in the release position or braking position occupied by the arcuate disaster prevention material for hand protection, and Fig. 13 is a prepared chain brake device according to the third embodiment of the present invention. Fig. 14 is an enlarged side view of the chain brake device shown in Fig. 13 immediately after the release is performed using the bow-shaped disaster prevention material for hand protection;
Fig. 5 shows the trigger returned to the ready position and swiveled and the actuating member locked by the locking mechanism, and a side view showing the chain brake device of Fig. 14 in the braking position, and Fig. 16 shows the chain brake device in the braking position. 14 is a side view showing the chain brake device of FIG. 14 in a state in which the actuating member is locked through an adjustment member connected to the pressure member, and in a braking position after the release is performed by the pressure member; 17 is a side view of the rear grip portion of the power chainsaw of FIG. 10 shown with the pressure member in operative connection with the throttle lever, and FIG. 18 shows the pressure member and the throttle lever in the locked position. 17, and FIG. 19 shows the pressure member and throttle lever arranged in parallel on the grip of the second embodiment of the power chainsaw of FIG. 10 in an unpressed state. FIG. 20 is a schematic diagram showing the pressure member and throttle lever of FIG. 19 in a pressed state, and FIG. 21 is a third embodiment of the grip of the power chainsaw of FIG. 22 is a schematic diagram showing the pressure member located inside the grip and cooperating with the throttle lever in an unpressed state; FIG. 22 shows the throttle lever and pressure member of FIG. 21 in a pressed state; FIG. It is a schematic diagram. [Explanation of symbols] 1, 1b...power chainsaw, 2...the support grip, 3...saw blade, 4, 4e, 4f...rear grip, 5, 5
d, 5e, 5f...Throttle lever, 6, 6',
6c, 6d, 6e...Pressure member, 6f...Hook-shaped intermediate member, 7, 7', 7c...Bowden type operation cable, 8, 8', 8b, 8c... Actuation member,
9, 9', 9b... chain brake device, 10,
10b... Brake member, 11... Brake spring, 12... Brake band, 13... Brake drum, 14... One end of brake band, 15...
One end of the brake spring, 16, 16b, 16
c...Casing, 17...Crankshaft, 18,
18b, 18c...Archive-shaped disaster prevention material for hand protection, 18
b'...Triarm-shaped end, 19, 19b... Entrainment element, 2
0, 20', 20c...Lever-shaped locking member, 21, 21c...Intermediate lever, 22...Shaft fixed to the casing, 23...First arm, 24...
...Latch groove, 25...Second arm, 26...Other end of brake spring, 27...Third arm, 28...Other end of brake band, 30...Free end, 31, 31b...
...partial circular locking opening, 32, 32b...free end, 33...limiting wall, 33a...flat outer surface,
34...Finger-shaped protrusion, 35, 35'...
...rounded chamfered end, 35a...locking pin,
35a'...pin, 35b...end, 36...vertical edge, 37, 37b...first lever arm of the locking member, 37a, 37b', 37c'...second lever arm of the locking member, 38... ...shaft, 39...double spring,
39a... One end of the double leg spring, 40b... Notch, 41... The other end of the double leg spring, 42c...
First stopper piece, 43b...guide slot,
44... One end of the actuating member, 46, 46',
46b, 46c... Rotating shaft, 47, 47'... Support plate, 47'a... Opening edge, 47b, 47c...
...Support openings, 47b', 47b''...First and second wall sections, 48, 48b...Knitting joints, 49
...Contact edge, 50,50'...First contact part,
50b...First contact portion formed by the web end surface, 51b, 51b', 51c, 51c'...Leverage arm, 51b'', 51c''...Free end portion, 52...Rotary orbit of entrainer, 53, 53'...second contact portion, 54...pressing spring, 56 entrainer shaft, 57...
Cam base circle, 58b, 58c...One end of the operating cable, 59...Cam apex, 60...Switching unit, 61...Disk, 62...Tension spring, 62b...Press spring, 63...Bowden One end of the Bowden type operation cable, 64... Disk outer surface, 65... Stopper, 66... Other end of the Bowden type operation cable, 67... Rod, 67
b, 67c... Entrainer as the first arm of the tri-armed end, 67b', 67c'... Free end, 68... One end of the rod, 69... Rotating shaft, 69b... Rotating Shaft, 70...Other end of rod, 71, 71
b, 71c...Roller, 72c...Switching member,
73...bottom, 74c...outer edge, 76c...second
Stepped portion, 77c... Second stopper piece, 78c... Leaf spring, 79c... Overhanging edge, 80c, 81c
...Edge section, 82d...Double leg spring, 83d...
Shaft, 84d, 85d... Spring leg piece, 86d... End wall, 87d... Free end, 88d... Locking port, 8
9d...Press spring, 90e...Finger, 90e'...Forefinger, 91f...Hook end, 92f...Pivot end, 93f...Pivot point, 94f...Press spring, 9
5f...Throttle lever link, 96f...Elongated hole slot, 97f...Stepped portion, 98f, 99f...
...Curved edge section, 100b...Web, 101b,
101c...Second arm of the triarm-like end, 102b...
Third arm of triarm-like end, 104c...first step part, 1
05c...pressure spring, F...contact force, G...straight line, P...arrow indicating the turning direction of the locking member, P'...arrow indicating the load direction of the pressure spring,
P''...Arrow indicating the direction of pressure, P...Arrow indicating the rotation direction of the disk, P''''...Arrow indicating the rotating direction of the actuating member, 1... Distance from the pivot axis, M...
...center of curvature, Gb... pivot point, W... line of action of spring force.

Claims (1)

[Scope of Claims] 1. A trigger is connected to a locking member and a brake member, the brake member is disposed in a brake band surrounding a brake drum, and the brake member is locked by a locking mechanism. ,
actuating a spring-loaded brake for a power chainsaw having a drive engine of the type in which said brake band is held in a ready position spaced from a brake drum against the force of a brake spring engaging a brake member; In a chain brake device for
In the zero braking position, the driver 19 is brought into the path of motion and is connected in a relatively rotationally fixed manner to the crankshaft 17 as a drive member which is rotationally driven by the drive engine. Characterized by
Chain brake device. 2. In the ready position, the brake element 10 and the locking element 20, which is configured as a spring-loaded two-bowl lever, are connected via an open knitting joint 48 on one side, which is moved beyond the extended position. Chain braking device according to claim 1, characterized in that the knitting joint is held in the ready position by an actuating member (8) operatively connected to a trigger (6). 3. The knitting joint 48 is constituted by the first lever arm 37 of the locking member 20 and the intermediate lever 21 pivotally connected to the brake member 10, and the locking member 20 serves as the locking member. The first lever arm has a locking pin 35a protruding from the arm side surface, and a support opening 47 of the actuating member 8 is disposed in the locking pin, and the support opening 47 engages the locking member 20. Chain brake device according to claim 1 or 2, having two mutually facing contact surfaces 50, 53 for the stop pin 35a. 4. A cam-shaped entrainer 19 mounted on the crankshaft 17 is movable along a rotational track 52 to rotate the entrainment member 20, and the entrainment member 20 is movable along the rotational track 52 of the entrainment member 19.
The locking member 20 is held in a locked state by locking mechanisms 8, 20, 21 between the first lever arm 37 and the actuating member 8. A chain brake device according to any one of claims 1 to 3. 5. The intermediate lever 21 is spring-loaded in the direction of the ready position, at least in the braking position of the chain brake device and upon pivoting of the locking element 20 into the rotational track 52 of the entrainer 19;
9 has a cam surface along its entire circumference such that the crankshaft torque necessary for twisting the twisting member 20 is made constant via the cam, Claims 1 to 4 The chain brake device according to any one of the preceding paragraphs. 6. such that the line of action of the contact force F at the contact point between the locking pin 35a and the support opening 47 has one lever arm relative to the rotation center 46 of the actuating member 8;
A chain brake device according to any one of claims 1 to 5, wherein the actuating member 8 is eccentrically supported. 7. The trigger is connected to a locking member and a brake member, the brake member is disposed in a brake band surrounding the brake drum, and the brake member is connected by a locking mechanism,
The brake band is held in a ready position spaced apart from the brake drum against the force of a brake spring engaging the brake element, and the locking element is in the path of movement of the entrainer in the braking position of the brake element. the entrainer is connected in a relatively non-rotatable manner to a crankshaft as a drive member rotationally driven by a drive engine, and the brake member and the locking member are in the ready position via a knitting joint. A spring load for a power chainsaw with a drive engine, of the type in which the formation joint is held by an actuating member operatively connected to a trigger as a hand protection bow of the power chainsaw. In the chain brake device for operating the brakes, the operating members 8b, 8c are connected to the stoppers 42b, 4
2c, and the stopper includes a trigger 18b,
A chain brake device characterized in that 18c is engaged with integrally molded arms 67b and 67c. 8 Stopper 42b, 42c is actuating member 8b, 8
The stopper piece extends at a substantially right angle from c, and the stopper piece forms the wall of the open-edged notch 40b, and the triggers 18b, 18 are inserted into the notch.
The arms 67b, 67c of c enter and the cutout 40b is located adjacent to a bearing opening 47b for a roller 71b supported on one end 35b of the locking member 20b. A chain brake device according to claim 7. 9 The first arms 67b, 67c have a second arm 101b integrally molded with the first arm, and the second arm loads the triggers 18b, 18c to the ready position and/or the release position. Spring 62b, 105c
are engaged, and the second arm 101b forms one screw arm of the toggle levers 101b, 103b, and the other screw arm 103b of the toggle lever
9. The chain brake device according to claim 7 or 8, wherein a spring 62b fixed to the casing and applying a load to the toggle lever is engaged. 10 Claims 7 to 9 include a third arm 102b disposed on the brake member 10b so that the arm 67b of the arcuate disaster prevention material 18b for protecting hands is disengaged into the brake band 12b. The chain brake device according to any one of the preceding items. 11 A locking mechanism 78c that keeps the actuating member 8c at the release position after release is disposed on the actuating member, and the locking mechanism 78c is attached to a notch formed by a stepped portion of the actuating member 8c. 76c, and when the actuating member 8c is in the braking position, it is kept in the inactive position by the spring force of the cocking member 20c that engages with the actuating member. A chain brake device according to any one of claims 7 to 10. 12 Switching member 7 pivotally mounted on the free end 58c of the tension link 7c for releasing the locking mechanism 78c
2c is provided, the switching member being slidable along a partially circularly curved outer edge 74c of the actuating member 8c and extending outwardly for the step 104c of the actuating member 8c. Extended stopper 77
c, the stopper abutting the stopper in the ready position of the actuating member.
Chain brake device as described in section. 13. Further triggers 6c, 6d are provided which are constructed as pressure members and are pivotably arranged in the rear grip of the power chainsaw, so that when the triggers are released, the locking mechanism 78c causes the switching member 72c to The locking with the actuating member 8c can be released by the force of the stopper 77c, and the trigger 6
d is in the ready position, the throttle lever 5d of the power chainsaw is lockable in the throttle fully open position, and one end 85d of the double leg spring 82d holding the throttle lever 5d in the pressed position is in the pressed position. The chain brake device according to claim 11 or 12, which engages with the locking port 88d of the pressed trigger 6d. 14. The trigger 6e and the throttle lever 5e provided on the rear grip are coaxially arranged in parallel so as to be located on the same side of the rear grip 4e and within the grip area of the operator's hand; Any one of claims 7 to 13
Chain brake device as described in section. 15 The chain brake device 9b is actuated by the operation of a throttle lever 5f, which is operatively connected to a hook-shaped intermediate member 6f pivotably supported in the rear grip 4f; A tension member 7f is attached to the member, and when the intermediate member 6f rotates the throttle lever 5f from the no-load operating position to the throttle fully open position, the throttle lever 5f becomes immovable.
Claims 7 to 14 bordering on
The chain brake device according to any one of the preceding paragraphs. 16 When the throttle lever 5f turns, the intermediate member 6f slides along the stepped portion 97f of the throttle lever, and the stepped portion
is located between two partially circular edge sections 98f and 99f having different radii of curvature, and when the intermediate member 6f is between the fully open throttle position and the no-load operating position, the edge with the larger radius of curvature 16. The chain brake device according to claim 15, wherein the edge section contacts the section 99f, and the center of curvature of the edge section is located on the pivot axis of the throttle lever 5f.