JPS635972Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic parking brake cable adjustment device.

Generally, a cable is used to transmit force from the parking brake lever to the braking area, but the cable stretches as it is used, and if left as is, the operation stroke of the parking brake lever will change and the feeling of operation will change. In addition, there is a risk that the braking force may become unstable or malfunction may occur.

Conventionally, for this purpose, a cable tension adjustment device was provided in the middle of the cable or in the transmission link, and the tension was adjusted during periodic inspections or whenever necessary.

However, with conventional adjustment devices, the cables are not adjusted all the time, and the cables can become overstretched between periodic inspections, creating a dangerous situation. The reality was that adjustments were difficult to make even if the need arose because they were installed in inconvenient or narrow locations.

The present invention was developed in view of the above problems, and provides an automatic adjustment device that detects the condition of the cable each time the parking brake lever is operated, and automatically increases the tension when the cable tension is weak. It is something to do.

The present invention will be described below based on embodiments shown in the drawings.

As shown in FIGS. 1 and 2, the parking brake lever 1 is pivotally attached to a sector base 2 fixed to the vehicle body with a pin 11 so as to be swingable, and a trunnion pin provided on a swing operating arm 12. When the transmission cable 3 is connected to the brake lever 1 and the brake lever 1 is raised, the locking pawl 15 is pivotally connected to the sector tooth 21 carved on the sector base 2 and the brake lever 1 with a pin 14 and biased in the engaging direction. are engaged to pull the transmission cable 3 and hold it in the braking state, and to release the braking, press the button 16 to release the sector tooth 21 and the locking pawl 1.
When the brake lever 1 is disengaged from the brake lever 5, the brake lever 1 is tilted down.

The adjustment device connects the transmission cable 3 to the trunnion pin 1
The connecting end is provided near the connecting end that connects to the cable 3. The connecting end is a threaded rod 31 having a threaded portion of a considerable length that allows for an adjustment margin for the cable 3 and for the attachment of related members.
The screw rod 31 is inserted into an insertion hole 13a drilled at right angles to the axial direction of a trunnion pin 13 attached to the swing operation arm 12 in parallel with the swing axis thereof, and an adjustment nut 32 is screwed onto the screw rod 31 on the protruding side to prevent the screw rod 31 from coming off, and the tension of the cable 3 is received by its end face 33. A relay coil spring 34 is further inserted into the tip of the adjustment nut 32, and a feed member 35 is attached by holding the relay coil spring 34 between the adjustment nut 32 and the feed member 35.
The adjustment nut 32 has a sideways protruding adjustment drive lever 36, which is attached to the tip of the threaded rod 31 so as to be rotatable and swingable. Here, it is screwed onto the threaded rod 31, but it may be freely rotatable and secured by a ring or pin to prevent it from coming loose. The end faces of the adjustment nut 32 and the feed member 35 are secured by a relay coil spring 34.
The relay coil spring 34 abuts against both ends of the
The relay coil spring 34 has teeth 37 which engage with the end of the adjusting nut 32, and this engagement forms a one-way transmission mechanism that catches and transmits rotation when the feed member 35 rotates in the forward direction of the adjusting nut 32, and engages so as to rotate freely in the opposite direction. The one-way transmission mechanism may be located either between the relay coil spring 34 and the adjusting nut 32 or between the feed member 35, and the other may be fixed. Also, a known one-way transmission mechanism may be used, such as using the peripheral surface of each member instead of the end surface, or using a clutch member between them. The feed member 35 is connected to its adjustment drive lever 36.
The brake lever 1 is driven by a drive member 17 which operates in response to a pivoting operation of the brake lever 1 to rotate and pivot.
The driving member 17 is pivotally mounted on the trunnion pin 13 so as to be freely rotatable, and is adapted to abut against an upper stopper 18 and a lower stopper 19 provided on the brake lever 1, so as to swing at an appropriate swing stroke in response to the swinging operation of the brake lever 1. Since a split hole 17a formed at the free end of the driving member 17 is engaged with the adjustment driving lever 36, the feed member 35 also rotates and swings.
The feed member 35 relatively swings about the center, but it can be fixed to the brake lever 1 or made integral with it, and engaged with the adjustment drive lever 36 via an engagement long hole to rotate and swing the feed member 35 by an appropriate stroke. In short, it is sufficient that the swing stroke of the brake lever 1 is converted into an appropriate swing stroke of the feed member 35 to drive it.

Next, the action will be explained. When the brake lever 1 is swung in the direction of raising the brake lever 1 for braking, the drive member 17 rotates freely until the brake lever 1 swings considerably, and when the lower stopper 19 comes into contact with it from below, the drive member 17 rotates in a reverse direction as shown in the figure. It swings clockwise, and the feeding member 35 also rotates via the adjustment drive lever 36. This direction is the transmission direction of the one-way transmission mechanism, and the relay coil spring 34 adjusts the rotational force with the adjustment nut 3.
2. At this time, if the cable 3 is in a normal state, it should be pulled considerably and have a strong tension. Since this tension is received by the end face 33 of the adjustment nut 32, its rotational and sliding resistance is large, and the adjustment nut 32 does not rotate and its position does not change, only the relay coil spring 34 is bent. When the brake lever 1 is returned to its original state, the feeding member 35 simply rotates and swings. However, if the cables in the transmission system are stretched and stretched, the tension in the cable 3 will not increase even if the brake lever 1 is raised and swung, and the tension in the cable 3 will not increase.
Since the rotational sliding resistance of the end face 33 of the cable 2 is also low, the adjusting nut 32 rotates and moves forward due to the rotational force transmitted to the relay coil spring 34, thereby tightening the cable 3. When the brake lever 1 is returned, the engagement of the one-way transmission mechanism idles, and the end of the relay coil spring 34 rides over the teeth 37 by the amount that the adjustment nut 32 rotates, and the feeding member 35 returns to its original position while the adjustment nut 32 is rotated. Return to That is, when the cable 3 is tightened and the tension is adjusted by the raising/lowering action of the brake lever 1, the tension is adjusted in direct response to the decrease in the tension of the cable 3, regardless of the raising/lowering stroke of the brake lever 1. It will be adjusted. Therefore, there is little variation in the raising/lowering stroke of the brake lever 1, and the cable 3 is tightened and adjusted automatically in conjunction with the normal operation of the brake lever 1 without any other operation.

In the above embodiment, the adjustment nut 32 is rotated when the brake lever 1 is raised, but the direction of the screw and the way in which the drive member 17 or the adjustment drive lever 36 are mounted are changed, and the relay coil spring 34 is rotated. It goes without saying that by appropriately changing the design, such as changing the strength, the adjustment nut 32 can be rotated to make adjustments when the brake lever 1 is pushed down.

According to the parking brake cable automatic adjustment device according to the present invention, the tension of the transmission system cable is automatically checked when the brake lever is operated, and when the tension is weak, the tension is adjusted to increase.
Moreover, there is no need to take any special consideration for adjustment, and the fluctuations in the brake lever's up/down stroke due to cable elongation, etc. are minimized, so the vehicle's parking brake can always be maintained in an appropriate state. , safety is ensured, maintainability is improved, and maintenance is free.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, with FIG. 1 being a partially exploded overall perspective view, and FIG. 2 being an enlarged exploded perspective view of the main parts. 1... Brake lever, 13... Trunnion pin, 17... Drive member, 3... Cable, 31...
... Threaded rod, 32 ... Adjustment nut, 34 ... Relay coil spring, 35 ... Feeding member, 36 ... Adjustment drive lever.

Claims (1)

[Claims for Utility Model Registration] (1) A cable provided near the connecting end of a transmission cable that connects to the swing operating arm of the parking brake lever, the connecting end being a threaded rod having a threaded portion of considerable length. The end of the threaded rod that is inserted through the trunnion pin provided on the swing operation arm and protrudes from the trunnion pin receives the tension of the transmission cable on its end surface, so that the threaded rod does not come off. an adjusting nut is screwed together, and a feeding member equipped with an adjusting drive lever is further provided on the distal end side of the threaded rod than the adjusting nut, and a relay coil spring is interposed between the feeding member and the adjusting nut so that the feeding member can rotate and swing. A unidirectional transmission is provided between the relay coil spring and the adjusting nut or the feeding member, and at least one of the adjusting nut or the feeding member is provided with a one-way transmission that transmits rotational force only in the forward direction of the adjusting nut when the feeding member is rotated and swung. A mechanism is provided, and the parking lever is provided with a drive member that engages with the adjustment drive lever of the feeding member and rotates and swings the feeding member in response to a swinging operation of the parking brake lever. An automatic parking brake cable adjustment device characterized by: (2) The one-way transmission mechanism is provided between the end of the relay coil spring and the end face of at least one of the adjusting nut or the feeding member, and the end of the relay coil spring is provided in one direction by the teeth carved on the end face. The automatic adjustment device for a parking brake cable according to claim 1, characterized in that the parking brake cable is meshed so that it can be engaged only from the outside. (3) The driving member is rotatably pivotally connected to a trunnion pin through which a transmission cable is inserted, and engages with a stopper provided on the parking brake lever with play, thereby regulating the swing stroke. An automatic adjustment device for a parking brake cable according to claim 1 or 2 of the utility model registration claim.