JPS6121624Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention is a device for transmitting the rotational torque of the input shaft to the output side, and the clutch is designed to stop the rotation of the output side the moment the torque transmission is cut off.
This relates to a brake device, in particular, which is attached to a power lawn mower and uses a brake to instantly stop a cutting blade rotating via a clutch mechanism when the clutch is disengaged.

For example, when moving a power lawn mower to change the lawn mowing location, it is necessary to stop the rotation of the cutting blade for safety reasons. In this case, it is possible to stop the rotation of the cutting blade by stopping the rotation of the engine, but if the cutting blade is to be used continuously, it is necessary to restart the engine. For this reason, it is desirable to stop the rotation of the cutting blade without stopping the engine.

Therefore, as shown in US Pat. No. 4,141,439, some front-push type power lawn mowers are equipped with a clutch/brake device below the engine to stop the mowing blade without stopping the engine. In this device, a drive disk is provided on an input shaft arranged vertically on a power lawn mower, a driven disk arranged below the drive disk is rotatably supported by the input shaft, and a clutch is connected between both disks. A ring-shaped operation cam member is rotatably provided on the outer periphery of the drive disk with a disk interposed therebetween, and the cam ring is fixed to the housing above the operation cam member,
A cam ball is interposed between the operating cam member and the cam ring, a ring-shaped brake lining is disposed between the lower surface of the operating cam member and the driven disc, and the driven disc is pushed upward by the clutch spring to close the clutch disc. The driven disc is connected to the drive disc through the input shaft, and the driven disc is rotated by the rotational torque of the input shaft, and the operating cam operates the cutting blade fixed to the disc installed outside the sealed fixed cover that rotates integrally with the driven disc. The member is rotated by a predetermined angle and the operating cam member is pushed down by the cam ball to press the brake lining against the driven disc to apply braking, and the driven disc is moved downward by this pressing force to engage with the driving disc. is shut off and the rotation of the cutting blade is stopped.

By the way, in this device, a single guide pin installed upright on the operating cam member penetrates a circumferential guide groove formed in the cam ring and projects upward, and a brake operating lever is engaged with the tip of the guide pin. By rotating the lever, the operating cam member is rotated by a predetermined angle via a pin to perform braking.

For this reason, each time the operating cam member rotates, a force perpendicular to the axial direction of the guide pin is applied to the guide pin, which causes the guide pin to become fatigued, resulting in a durability problem.

In view of this, the present invention has been developed so that the operating cam member is guided by the guide pin so that it can be switched at a predetermined angle, and by rotating the operating cam member, the operating cam member is guided by the guide pin at right angles to the axial direction of the guide pin. The object of the present invention is to provide a clutch/brake device in which the durability of the guide pin is improved and the durability of the guide pin is improved.

In order to achieve the above object, the present invention includes a cam plate fixed to the main body perpendicular to the input shaft, a torque transmission disk that rotates integrally with the input shaft, and a torque transmission disk that is closer to the input shaft than the torque transmission disk. an output member that is rotatably provided on the input shaft on the distal end side, and an output member that rotates integrally with the output member and is movable in the axial direction of the input shaft, and is located between the torque transmission disk and the output member; a lining plate that is arranged and has a larger diameter than the torque transmission disk; a clutch spring that biases the lining plate toward the torque transmission disk and engages the lining plate with the torque transmission disk when braking is not applied; and the cam plate and the torque transmission disk. A pressurer is disposed between the transmission disk and movable in the axial direction of the input shaft, and has a brake torque receiving surface that can engage the lining plate on the outside of the outer peripheral edge of the torque transmission disk. a plate, and is disposed between the cam plate and the main body, facing the cam plate with a cam ball interposed therebetween, so as to be movable in the axial direction of the input shaft and rotatable by a predetermined angle in the circumferential direction. an operating cam member, and a brake spring that urges the pressure plate toward the lining plate and engages the pressure plate with the lining plate during braking, and an appropriate number of guides attached to the pressure plate. A pin is erected through the cam plate, and the tip of the guide pin is inserted into a circumferential guide groove formed in the operating cam member to allow rotation of the operating cam member to connect the pressure plate and the operating cam. It is characterized in that the members are locked so that they can move integrally in the axial direction of the input shaft.

Hereinafter, an embodiment in which the present invention is applied to a power lawn mower will be described with reference to the drawings.

A cam plate 1 is fixed to the lower surface of an engine mounting 3 serving as the main body by mounting bolts that pass through a plurality of mounting holes 2 formed around the periphery of the cam plate 1. In the center of this cam plate 1 is an input shaft 4.
A through hole is formed, from which the input shaft 4 projects downward perpendicularly to the cam plate 1.

A torque transmission disk 5 is fixed to the input shaft 4 via a collar member 6 fitted to the tip thereof. A bearing 7 is fitted into the lower part of the collar member 6, a washer 8 is applied from the lower end surface of the collar member 6, a fixing bolt 9 is screwed onto the tip of the input shaft 4 via a spring washer 10, and the bearing 7 is held on the collar member 6.

An output member 11 is fitted into the bearing 7, and is rotatably supported on the front end side of the torque transmission disk 5 of the input shaft 4. This output member 11
has a larger diameter than the torque transmission disk 5, has a through hole for the collar member 6 formed in the center, and bends its outer periphery downward to form a fitting part for the bearing 7, and the outer periphery of the fitting part is bent horizontally to form a mounting plane, and the blade set screw hole 1 is inserted into this mounting plane.
2, a cutting blade (not shown) is fixed to the bottom of the mounting plane through a blade set screw hole (not shown) screwed into the screw hole 12, and guide grooves 11a are formed at four equally spaced locations on the outer periphery. to form.

A lining plate 13 is arranged between the torque transmission disk 5 and the output member 11 so as to be axially movable and rotatable with respect to the input shaft 4 .
This lining plate 13 has approximately the same diameter as the output member 11, has a through hole formed in the center in which the fitting portion of the bearing 7 of the output member 11 is loosely inserted, and faces the torque transmission disk 5 on the outer periphery thereof. A lining mounting surface is formed on the outer periphery of the mounting surface at a position outside the periphery of the torque transmission disk 5, and a braking surface is formed concentrically around the input shaft 4. guide groove 11a
The guide piece 13a is placed at a position corresponding to the output member 11.
The guide piece 13a is bent in the direction in which the guide piece 13a engages with the guide groove 11a to allow movement of the input shaft 4 of the lining plate 13 in the axial direction, and when the lining plate 13 is rotating, the guide piece 13a When the output member 11 is rotated through the guide groove 11a and the lining plate 13 stops, the guide groove 11a is regulated by the guide piece 13a and the output member 11 also stops rotating. A clutch spring 14 is compressed between the lining plate 13 and the output member 11, and biases the lining plate 13 in the direction of the torque transmission disk 5, thereby applying torque to the clutch lining 15 fixed to the lining mounting surface of the lining plate 13. It is designed so that it can be pressed into contact with the transmission disk 5.

A pressure plate 23 is disposed between the cam plate 1 and the torque transmission disk 5 and is loosely fitted onto the input shaft 4. This pressure plate 23 has a larger diameter than the torque transmission disk 5, and a portion located on the outer periphery of the torque transmission disk 5 is bent downward, and further bent in the outer periphery direction to form the lining plate 13. A brake torque receiving surface is formed opposite to the braking surface of the input shaft 4, and a ring-shaped brake lining 29 is attached to this receiving surface.
It is fixed concentrically with the

An operating cam member 16 is disposed between the engine mounting 3 and the cam plate 1, and its inner circumference is inserted into the input shaft 4 through a dust seal 18 so as to be movable and rotatable in the axial direction of the input shaft 4. and then attach the operating rod 20 to the operating cam member 16 with the bolt 19.
By fixing it with and operating the operating rod 20,
The operating cam member 16 is rotated by a predetermined angle.

On the surface of the cam plate 1 facing the operating cam member 16, three ball clamps 22 are formed at equal intervals, the ball clamps 22 becoming deeper and inclined in the reaction direction of the operating rod 20, and on the other hand facing the cam plate 1 of the operating cam member 16. A ball clamp 21 that is inclined and deepens in the operating direction of the operating rod 20 is formed on the surface corresponding to the ball clamp 22. A cam ball 17 is provided between these ball clamps 21 and 22 so as to roll on each inclined surface.
When the cam ball 17 is at the deepest position of the ball clamps 21 and 22, the operating cam member 16
It is located closest to the cam plate 1, and this state is the initial position of the operating rod 20.

A suitable number of brake springs 24 are compressed between the cam plate 1 and the pressure plate 23, and constantly urge the pressure plate 23 toward the lining plate 13. and,
The spring force of this brake spring 24 is set larger than the spring force of the clutch spring 14.

A guide pin 2 is provided near the brake spring 24 on the outside in the radial direction of the pressure plate 23.
5 is the engine mounting 3 parallel to the input shaft 4
Three guide pins are provided at equal intervals in the direction, and the shaft portion 25a of the guide pin 25 is connected to the cam plate 1.
The distal end portion 25b protrudes from the circumferential guide groove 26 formed in the operating cam member 16,
The operating cam member 16 is fixed to the upper surface of the operating cam member 16 by a retaining ring 28 via a flat washer 27.
The pressure plate 23 holds the cam ball 17 at the deepest position of the ball clamps 21 and 22 by the brake spring 24, presses the brake lining 29 of the lining plate 13, and presses the clutch lining 15. maintains a state separated from the torque transmission disk 5. And the operating rod 20
When activated, the pressure plate 23 is guided by the guide pin 25 and moves in the axial direction of the input shaft 4, which prevents the pressure plate 23 from falling and also reduces the imbalance of the brake spring 24. Its movement is parallel to the lining plate 13 and smooth, allowing stable engagement and engagement of the clutch and quick braking. A cover 30 is attached to the cam plate 1 with screws 31.

Next, the operation of this embodiment will be explained. 1st
In the braking state in which the brake spring 24 is stretched with a set load as shown in the figure, the cam ball 17 is located at the deepest position of the ball clamps 21 and 22, so that the distance between the operating cam member 16 and the cam plate 1 is minimized. The operating rod 20 is in the initial position, the lining plate 13 is pressed by the pressure plate 17, the clutch spring 14 is contracted, and the clutch lining 15 is separated from the torque transmission disk 5 without contacting it.
Therefore, the rotational torque of the input shaft 4 and the torque transmission disk 5 is not transmitted to the output member 11,
The mower blade (not shown) remains stationary and the engine maintains an idling operating state.

Next, when rotating the cutting blade, pull the cable (not shown) connected to the operating rod 20, and
When rotated in the direction of arrow A in the figure, the operating cam member 16 moves into the guide groove 26 relative to the guide pin 25.
is guided and rotated by a predetermined angle relative to the cam plate 1 fixed to the engine mounting 3. At this time, the cam ball 17 rolls and rises along the inclined surfaces of the ball clamps 21 and 22, and as a result, the operating cam member 16 rotates and moves away from the cam plate 1. 23 moves toward the cam plate 1 via a guide pin 25 against the brake spring 24. As this movement progresses, the lining plate 13 follows the brake lining 29 while maintaining its pressure contact state due to the spring force of the clutch spring 14 and moves in the direction of the torque transmission disk 5. When the clutch lining 15 contacts the torque transmission disk 5, The lining plate 13 begins to rotate while being dragged by the rotation, and becomes in a so-called half-clutch state. Furthermore, when the clutch spring 14 expands with the contraction of the brake spring 24 and the clutch lining 15 is pressed against the torque transmission disk 5, the rotational force of the lining plate 13 increases accordingly.
Next, when the pressure plate 23 moves further upward, the brake lining 29 separates from the lining plate 13 and the engaged state is released, and the lining plate 13 begins to rotate together with the torque transmission disk 5, and the clutch is connected. . As a result, the power of the input shaft 4 is transmitted to the output member 11 via the collar member 6, the torque transmission disk 5, and the lining plate 13, causing the cutting blade to rotate in the direction of arrow B in FIG.

When the cable is released, the pressure plate 23 is pushed down in FIG. 13
is pushed downward to separate the clutch lining 15 from the torque transmission disk 5, disconnecting the lining plate 13 from the torque transmission disk 5, thereby braking the rotation of the lining plate 13 and stopping the rotation of the cutting blade. Stop.

Accordingly, the operating rod 20 and the operating cam member 16 rotate together in the direction of arrow C in FIG.
It is held at the deepest position of 1 and 22.

As described above, according to the present invention, an appropriate number of guide pins are installed on the pressure plate so as to pass through the cam plate, and the tips of the guide pins are attached to the operating cam member to allow rotation of the operating cam member. Since the rotation of the operating cam member causes the pressure plate to move in the axial direction of the input shaft, the lining plate is pressed against or separated from the torque transmission disk that rotates together with the input shaft, thereby disconnecting and disengaging the clutch. During this process, the pressure plate is guided by the guide groove and moves in the axial direction of the input shaft, preventing the pressure plate from tipping over and reducing the imbalance of the brake spring. It can move parallel to the plate and smoothly, making it possible to achieve stable engagement and engagement of the clutch and quick braking.Moreover, the guide pin installed upright on the pressure plate moves in the circumferential direction of the operating cam member. Since the guide pin is engaged with the guide groove of the guide pin, even if the operating cam member is switched by a predetermined angle during a braking operation, no force perpendicular to the axial direction is applied to the guide pin, thereby improving the durability of the guide pin.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, with FIG. 1 being a sectional front view and FIG. 2 being a plan view. DESCRIPTION OF SYMBOLS 1...Cam plate, 4...Input shaft, 5...Torque transmission disk, 11...Output member, 13...
Lining plate, 14... Clutch spring, 16... Operating cam member, 17... Cam ball, 20... Operating rod, 23... Pressure plate, 24... Brake spring, 25... Guide pin, 26... Guide groove, 27...flat washers, 28...retaining ring.

Claims (1)

[Scope of utility model registration request] a cam plate 1 fixed to the main body perpendicular to the input shaft 4; a torque transmission disk 5 rotating integrally with the input shaft 4; An output member 11 rotatably provided on the input shaft 4, and an output member 11 between the torque transmission disk 5 and the output member 11, which rotates integrally with the output member 11 and is movable in the axial direction of the input shaft 4. Torque transmission disk 5
a clutch spring 14 that biases the lining plate 13 in the direction of the torque transmission disk 5 and engages the lining plate 13 with the torque transmission disk 5 when braking is not applied; The torque transmission disk 5 is disposed so as to be movable in the axial direction of the input shaft 4.
The lining plate 1 is placed on the outside of the outer peripheral edge of the lining plate 1.
between the cam plate 1 and the main body, a pusher plate 23 formed with a brake torque receiving surface that can be engaged with the input shaft 4, and facing the cam plate 1 with the cam ball 17 interposed An operation cam member 16 disposed to be movable in the axial direction and rotatable by a predetermined angle in the circumferential direction, and the pusher plate 23 are urged in the direction of the lining plate 13 to push the pusher plate against the lining plate 13 during braking. a brake spring 24 that engages the pusher plate 23;
An appropriate number of guide pins 25 are attached to the cam plate 1.
The tip end 25b of the guide pin 25 is inserted into a circumferential guide groove 26 formed in the operating cam member 16 to allow rotation of the operating cam member 16, thereby connecting the pusher plate 23 and the operating cam. Member 16
A clutch/brake device characterized in that the input shaft 4 is movably locked in the axial direction of the input shaft 4.