JPH0123877Y2 - - Google Patents

Description

[Detailed description of the invention] [Purpose of the invention] (Field of industrial application) The present invention relates to a parking brake for vehicles such as automobiles, and particularly to a device for preventing return failure of the operating rod of a parking brake equipped with an operating load detection device. It is.

(Prior Art) A conventional parking brake has a means for notifying the operator when the stroke of the operating rod exceeds a set value by operating the handle.
Lamps placed in appropriate locations are designed to light up. However, this lamp does not allow the parking condition to be maintained safely even if the operating rod is pulled beyond a predetermined stroke and the lamp lights up due to parking brake assembly errors, wear of the lining, or loosening of the cable. A case may occur in which the brake is not loaded with the same operating load. Therefore, a cable tension detection device that prevents such a situation from occurring is proposed in Japanese Utility Model Application Publication No. 51-34129. This device is provided in the middle of a cable, and includes a cylinder body to which one end of the cable is fixed, and a piston rod fitted into the cylinder body and to which the other end of the cable is fixed. , an elastic body for setting cable tension that is stretched between the piston surface of the piston rod and the bottom surface of the cylinder and resiliently retracts in a direction to bring both ends of the cable closer together; a conductor capable of contacting an integral part of the cylinder when the parts are moved apart from each other so that the piston moves within the cylinder to set the cable tension at a cable tension sufficient to ensure that the vehicle remains parked. The lamp is turned on when the conductor overcomes the repulsive force of the elastic body and comes into contact with an integral part of the cylinder.

(Problems to be Solved by the Invention) In the conventional device described above, since the lamp lights up in response to the application of a predetermined operating load, it is possible to prevent the above-mentioned situation from occurring. However, in this case, since the tension detection device is interposed in the middle of the cable, all of the weight of the detection device is carried by the cable, and when the parking brake is not activated, the cable is not bent by the weight of the detection device. There is a problem in that the cable's durability is deteriorated due to the force acting on it.

Further, the load on which the parking brake handle is pulled varies depending on the situation, and the detected load is set depending on the necessity of the vehicle, but in reality, the handle will be pulled when the set load is exceeded. Therefore, in the conventional device described above, although the relative rotation between the cylinder body and the piston rod is regulated, there is no means for regulating relative movement in the axial direction, so the tensile load applied to the handle is used to set the cable tension. Acts on the elastic body and conductor, etc., and applies a load greater than the set load to the elastic body and conductor for setting cable tension,
This state will be maintained in the parked state. As a result, in this device, deformation and damage of the cable tension setting elastic body, the conductor, etc. are induced, and there is a practical disadvantage in that these deteriorate early and have no durability.

These problems can be solved by connecting the parking brake with a cable to a lever whose one end is pivotably connected to the vehicle body, and by connecting a sleeve to the other end of the lever.
The other end of a ratchet toothed operating rod with a handle attached to one end is inserted into the sleeve, a pin fixed to the other end of the operating rod so as to intersect with the operating rod is inserted into the elongated circumferential hole of the sleeve, and the In a parking brake of a type in which the operating rod is urged to rotate in one direction relative to the sleeve by a return spring whose both ends are engaged with a pin and the sleeve, the width of the circumferential elongated hole is set to be larger than the diameter of the pin. This allows the operating rod to move in the axial direction by a predetermined amount with respect to the sleeve, and a displacement take-out plate for taking out the axial displacement of the operating rod is provided in the sleeve, and a connection between the displacement take-out plate and the sleeve is provided. The load is transmitted from the operating rod to the sleeve prior to the load transmission to the pin by an operating load transmitting spring interposed with a preload applied thereto, and the operating load transmitting spring is compressed. When the microswitch is actuated by the displacement take-out plate, it is fixed to the sleeve, and when the operating rod moves in the axial direction by a predetermined amount with respect to the sleeve, the pin transmits a load from the operating rod to the sleeve. This problem can be solved by configuring the operating load detection device in this way. In this configuration, it is preferable to apply a preload to the spring for transmitting the operating load in order to reduce the invalid stroke of the operating rod as much as possible, but if this preload is constantly applied to the operating rod, the operating rod will have a frictional load. Due to the added dynamic resistance force, the operating rod cannot be returned by the force of the return spring that returns the operating rod to a predetermined rotational position (the operating handle assumes a predetermined posture with good operability) when the parking brake is released. Although this return failure can be resolved by increasing the force of the return spring, the rotational force of the operating handle increases when the parking brake is released, causing problems such as a worsening of the operating feel.

Therefore, the present invention solves the problems of the conventional device described above, and also prevents the operating rod from returning incorrectly by preventing the force of the spring for transmitting the operating load from being applied to the operating rod when the parking brake is not activated. Take it as a challenge.

[Structure of the idea]

(Means to solve the problems) The measures taken to solve the above problems are:
A parking brake is connected by a cable to a lever whose one end is pivotally connected to the vehicle body, a sleeve is pivotally connected to the other end of the lever, and the other end of a ratchet toothed operating rod with a handle attached to one end is connected to the sleeve. A pin that is fixed to the other end of the operating rod so as to intersect with the operating rod is inserted into the elongated circumferential hole of the sleeve, and a return spring that has both ends locked to the pin and the sleeve is used to tighten the operating rod. In a parking brake of the type in which the shaft is rotationally biased in one direction relative to the sleeve, the axial width of the circumferential elongated hole is set to be larger than the diameter of the pin, so that the operating rod is axially biased by a predetermined amount relative to the sleeve. When the parking brake is activated, the pin engages with the circumferential elongated hole, allowing the sleeve to move integrally with the operating rod via the pin, and when the parking brake is applied, the other end of the operating rod is inserted into the sleeve. A displacement take-off plate is slidably provided on the sleeve and engages with the formed operation load transfer portion to take out the axial displacement of the operating rod, and a preload is applied between the displacement take-off plate and the sleeve. A spring for transmitting an operating load is interposed therebetween, and when the operating rod moves in the axial direction by a predetermined amount or less with respect to the sleeve and the spring for transmitting the operating load is compressed, it is actuated by the displacement take-out plate and sends a signal to the notification means. A locking member is fixed to the sleeve, and further includes a locking member that locks the displacement extraction plate with the operation load transmission spring when the parking brake is not activated, and restricts the amount of sliding of the displacement extraction plate with respect to the sleeve. Fixed to the sleeve, a slight play is set between the displacement take-out plate and the operating load receiving part so that the preload of the operating load transmitting spring is not applied to the operating rod when the parking brake is not activated. be.

(Function) According to the above-mentioned means, it is possible to solve the problems of the conventional device, and when the parking brake is released, the preload of the spring for transmitting the operating load is not applied to the operating rod, so that the operating rod returns to its original position. A spring ensures that it is returned to the specified position.

(Example) Hereinafter, an example of the present invention will be described based on the accompanying drawings.

In FIG. 1, a parking brake 1 is connected by a cable 6 to a lever 5, one end of which is pivotally connected to a vehicle body 4, via an equalizer 2. The operating lever 5 is connected to a ratchet toothed operating rod 8 via a load detection means 7. The bracket 3 is a pawl that engages with the ratchet teeth of the operating rod 8.
incorporated within. Now, when you pull the handle 9 and operate the operating rod 8, the lever 5 moves to the fulcrum 1.
0 and applies operating force to the parking brake 1 via the cable 6. When this operating force exceeds a predetermined value, this value is detected by the load detection means 7.
senses and generates a signal. This signal causes
An operator senses that a necessary load is being applied to the parking brake 1.

The specific structure of the load detection means 7 is shown in FIGS. 2 to 5. Reference numeral 11 denotes a hollow sleeve having a large diameter part 11a and a small diameter part 11b, and an operating rod 8 is loosely fitted into the small diameter part 11b of the sleeve, for receiving a pin 12 press-fitted into the operating rod 8. Elongated holes 11c are provided oppositely on the circumference. (See FIG. 5) The width of the elongated hole 11c is appropriately larger than the external shape of the pin 12, as shown by reference numeral F in FIG. Further, the large diameter portion 11a of the sleeve 11 is provided with a pin hole 11e for pivotally mounting the operating lever 5, and is also provided with a guide passage groove 11d for a member to be described later.

Reference numeral 13 denotes a collar which is an operating load transfer section in the present invention, and is fitted onto the outside of a threaded portion provided at the tip of the operating rod 8 extending into the large diameter portion 11a of the sleeve 11, and is fixed with a washer 14 and a nut 15.

On the collar 13 are a seat plate 16 and a displacement extraction plate 1.
7 is loosely fitted, the displacement take-out plate 17 is guided by the passage groove 11d of the sleeve 11, and the sleeve 11
An operating load transmitting spring 18 is interposed between the large diameter portion 11a and the bottom surface of the large diameter portion 11a. The mounting load of this spring 18 is set to the operating rod tensile load required for the parking brake. Reference numeral 19 denotes a snap spring, which is a locking member according to the present invention, provided in the large diameter hole of the sleeve 11, and restricts the leftward position of the seat plate 16 and the displacement extraction plate 17 by the operation load transmission spring 18. There is a slight play δ between the seat plate 16 and the collar 13.

Reference numeral 20 denotes an adjustment screw attached to the displacement extraction plate 17 with a nut 21, and a micro switch 22 is disposed on the sleeve 11 opposite to the adjustment screw 20. The distance H between the adjusting screw 20 and the protruding element 22a of the switch 22 is adjusted to be smaller than the dimension indicated by the symbol F. The micro switch 22 is activated by pushing in its protruding member 22a and sends a signal to a notification means (not shown), and 23 is a switch cord and 24 is a clip. Reference numeral 25 denotes a torsion spring for returning the rotation of the operating rod 8 of the present invention, which is arranged on the small diameter portion 11b of the sleeve 11, with one end facing the sleeve 11 side and the other end facing the pin. 12 (see FIG. 2), and biases the operating rod 8 against the sleeve 11 in the clockwise rotation direction.

The load detection device of the present invention is constructed as described above, and its effects will be described next.

Grip the handle 9 and insert the first and fourth
When a tensile load is applied in the direction of arrow B in the figure, this tensile load is transmitted to the sleeve 11 via the operating load transmitting spring 18, and the lever 5 is moved to the fulcrum 10.
It rotates around , and applies braking force to the parking brake 1. When this tensile load exceeds the set value, the spring 18 for transmitting the operating load is compressed, and the collar 13, seat plate 16, and displacement extraction plate 17 fixed to the operating rod 8 move toward the right toward the sleeve 11 as seen in FIG. Due to the relative displacement, the adjustment screw 20 collides with the protruding piece 22a of the switch 22, and the protruding piece 22
Press a to activate the switch 22. The actuation of this switch 22 activates a notification means (lamp, not shown) to notify the operator that a necessary operating load is being applied to the parking brake 1.

After the operating load transmitting spring 18 is compressed, the pin 12 engages with the circumferential elongated hole of the sleeve 11 to transmit the load, so that a large load can be applied to the lever 5. At this time, no matter how strong, how quickly, or how shockingly the operating force is applied to the operating rod 8, an undue load will not be applied to the spring 18 and the micro switch 22.
There is no deformation or damage to these materials, and their durability can be improved.

In addition, the load detection means 7 is housed in a sleeve 11 that is pivotally attached to one end of the lever 5, so that its own weight is not applied to the cable, which may impair the durability of the cable and the basic function of the parking brake. It is made sure that there is no such thing. Furthermore, even if the operating stroke of the micro switch 22 changes due to dimensional errors during processing or assembly, it can be adjusted appropriately using the adjustment screw 20, so it is possible to compensate for these errors and improve detection accuracy. can.

As is well known, the operating state of the parking brake is
It is maintained by the engagement of the ratchet teeth of the operating rod 8 with the pawls in the bracket 3.

As is well known, to release the parking brake, pull the handle 9 and operating rod 8 and rotate them against the torsion spring 25 to disengage the ratchet teeth and the pawl, and then release the handle 9 and operating rod 8. This is done by moving it back to the left in Figure 1. After releasing the parking brake, when the handle 9 is released, the handle and the operating rod 8 are returned to their original rotational positions by the torsion spring 25.
At this time, due to the slight play δ provided between the seat plate 16 and the collar 13, the preload of the spring 18 for transmitting the operating load is not applied to the operating rod 8, so that the operating rod 8 is not attached to the torsion spring. 25 to ensure that it is returned to the predetermined position.

[Effect of idea]

As described above, according to the present invention, there is no problem in returning the operating rod to the predetermined rotational position.
Moreover, the notification means can be activated in response to the operating load without deteriorating the operability.
It is highly effective in solving problems caused by insufficient operating load. Furthermore, according to the present invention, the durability of the cable, microswitch, and spring for transmitting operating load can be improved.

[Brief explanation of drawings]

FIG. 1 is an explanatory view showing an example of a parking brake mechanism, FIG. 2 is a front view of the main parts of the parking brake load detection means according to the present invention, FIG. 3 is a plan view of FIG. The figures are A-A in Figure 3, respectively.
FIG. 1...Parking brake, 5...Lever, 7
...Load detection means, 8...Operation rod, 11...
Sleeve, 12...Pin, 13...Color, 17
... Displacement extraction plate, 18 ... Operation load transmission spring, 19 ... Snap spring (locking member), 2
0... Adjustment screw, 22... Micro switch, 2
5...Torsion spring (return spring),
δ...play.

Claims (1)

[Scope of utility model registration request] A parking brake is connected by a cable to a lever whose one end is pivotally connected to the vehicle body, a sleeve is pivotally connected to the other end of the lever, and the other end of a ratchet toothed operating rod with a handle attached to one end is connected to the sleeve. A pin that is fixed to the other end of the operating rod so as to intersect with the operating rod is inserted into the elongated circumferential hole of the sleeve, and a return spring that has both ends locked to the pin and the sleeve is used to tighten the operating rod. In a parking brake of the type in which the shaft is rotationally biased in one direction relative to the sleeve, the axial width of the circumferential elongated hole is set to be larger than the diameter of the pin, so that the operating rod is axially biased by a predetermined amount relative to the sleeve. When the parking brake is activated, the pin engages with the circumferential elongated hole, allowing the sleeve to move integrally with the operating rod via the pin, and when the parking brake is applied, the other end of the operating rod is inserted into the sleeve. A displacement take-off plate is slidably provided on the sleeve and engages with the formed operation load transfer portion to take out the axial displacement of the operating rod, and a preload is applied between the displacement take-off plate and the sleeve. A spring for transmitting an operating load is interposed therebetween, and when the operating rod moves in the axial direction by a predetermined amount or less with respect to the sleeve and the spring for transmitting the operating load is compressed, it is actuated by the displacement take-out plate and sends a signal to the notification means. A locking member is fixed to the sleeve, and further includes a locking member that locks the displacement extraction plate with the operation load transmission spring when the parking brake is not activated, and restricts the amount of sliding of the displacement extraction plate with respect to the sleeve. It is fixed to a sleeve, and a slight play is set between the displacement take-out plate and the operating load transfer part so that the preload of the operating load transmission spring is not applied to the operating rod when the parking brake is not activated. ,
A mechanism to prevent the operating rod from returning incorrectly in a parking brake equipped with an operating load detection device.