JPS58209643A - Parking brake device - Google Patents

Abstract

PURPOSE:To aim at improvements in the simplification and operatability of setting jobs, by installing a load detecting device inclusive of a U-shaped plate spring in a brake lever member, in case of a device that makes a maximum braking state of a parking brake for large-sized automobiles, etc., detectable. CONSTITUTION:A device bearing the above caption rotates a cam 4 of a parking brake 2 via a brake lever member 6 by locking an end part 11a of an outer cable 11 belonging to a cable 10 and pulling an inner cable 12 with an operating lever set in motion. Then a brake shoe 5 is expanded by rotation of the cam 4 to press itself closely to a brake drum 3, thus braking force is secured right. In this case, the end part of the inner cable 12 is coupled with the end part of the said lever member 5 via a sensor 14' serving as a load detecting device. This sensor 14' is constituted of a U-shaped plate spring 20, which converts the tensile force of the cable 12 into displacement, and a detecting switch 21 for detecting said displacement.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a parking brake device used in large automobiles, etc., and particularly to a parking brake device that detects the maximum braking state of a parking brake provided in a drive system. 1. simplification of its structure and installation, and ease of floor cultivation.
0" above.

[Technical background and problems of the invention]

Generally, large vehicles such as trucks are equipped with a parking brake 2 at the rear of a transmission 1, which is a drive system, for braking the transmission, as shown in FIG. For example, as shown in FIG. 2, this i9-king brake 2 includes a brake drum 3 that is directly connected to the drive system, and within this brake drum 3, it is pivotally supported by a fixed system and is expanded by the rotation of a cam 4. It is comprised of a pair of brake shoes 5 that are in frictional contact with the inner surface vcM of the brake drum 3, and a brake lever member 6 that is swingably provided to allow the cam 4 to fully rotate. In order to remotely control the brake lever member 6 from the driver's seat, a link-type operating lever member 1 is provided at the driver's seat.
A cable 10 serving as a connecting member is provided between the application point side 8 of the operating lever member T and the application point side 9 of the brake lever member 6. This cable 10 is
Specifically, it consists of a tubular outer cable 11 serving as a guide cable and a power transmission inner cable 12 inserted into the outer cable 11, and the end 12a of the inner cable 12 is connected to the brake lever member 6 as described above. The end portion 11a of the outer cable 11 is fixed to the fixing system via the bracket 13.

By the way, when a large vehicle comes to a stop on a slope or the like, due to its large weight, the vehicle may descend and cause a serious accident if the vehicle is not fully activated. Also,
Recently, a brake lock device has been developed that maintains the hydraulic pressure of the brake system in that state when the switch is turned on while the foot brake is depressed.This brake lock device ensures that the parking brake 2 is operated reliably. The structure must be such that it can be turned on only when the switch is turned on.

To this end, various types of king brake devices have been proposed that have a function that can reliably detect whether the e-king brake 2 has been operated. However,
The parking brake device of Yakumei has inner cable 1.
The grip member 1 operates the load detection means having a structure in which a detection switch is turned on when the tension applied to the grip member 2 exceeds a set value.
A device installed on the force point side 8 of the load detecting means t, or a device interposed in the middle part of the load detecting means t cable 10 were used. However, in the case where the load detection means is operated and provided on the neck member, since the load detection means is on the input side of the cable 10, the load setting I of the load detection means [total cable efficiency or loss (Value assuming the worst cable efficiency) Since it is necessary to install a VC tail, the pulling force of the operating lever member 1 becomes heavy, resulting in poor operability.

On the other hand, in the case where the load detection means is provided at the intermediate portion 1c of the cable, as shown in FIG.
tl” knot, each outer couple 11+’, I
Bracket 151.1 near the gold sensor 14 at the end of lz
5z, and depending on the weight of the sensor 14, the sensor 14 itself may also need to be fixed, making the structure complicated and difficult to assemble.
There were drawbacks that led to increased costs. If this structure is adopted in an existing vehicle, IC1l'i requires a wide changeable part.In addition, by pulling the inner cable 12, the parking brake 2 is connected to the brake shoe 5 via the brake member 6 and the cam 4. The structure is such that the braking is performed by expanding the tension force, and when the tensile force is released, the spring 16 or the like returns to the original position.The same applies to the embodiments of the present invention. The purpose of this is to provide a parking brake device that is simple in structure and installation, has improved operability, and can reduce costs.
- To provide.

[Embodiments of the invention]

In FIG. 4, 6 is a brake lever member, 10 is a cable that is a connecting member consisting of an outer couple 11 and an inner cable 12, and 13 is an end m 11 a k of the outer cable 11 on the tension side of the brake lever member 6. The end 12aK of the HV/inner cable 12 is provided with a bracket provided to be fixed to a fixed thread of a transmission, etc.
A rod 1γ that supports the male threaded portion 17& is connected to the tip end of Fi. On the other hand, the power point side 9 of the brake lever member 6
A through hole 18 for loosely inserting the rod 17t is formed along the swinging direction of the rod 17t, and a sensor 14' serving as a load detection means is mounted on the return side of the brake lever member 6 in this through hole 18. A spherical seat 19 is formed for allowing the seat to swing freely.

The sensor 14' is mainly composed of a leaf spring member 20 for converting the tensile force of the inner couple 12 into displacement, and a detection switch 21 for detecting the displacement. The leaf spring member 20 is formed into a band-like temporary spring (i-U shape), and its -side 2QaK is provided with a spherical head 22 for seating on the spherical seat 19. Both sides 20a and 20bK of the member 20 including the ball head 22 are formed with shaft holes 23 and 24 through which the rod IT is inserted, and the rod IT is inserted into the shaft holes 23 and 24 from the ball head 22 side. A nut 25 is provided at the tip of the rod 11 for pressing the leaf spring member 20 in the direction of compression.
is screwed on. The spring constant or elastic force of this plate spring member 20 is determined by the tensile force of the inner cable 12 when the brake lever 91 member 16 is mediated by the parking brake 2.
When the tensile force of the inner cable 12, which is set to be larger than the maximum load required to apply a braking force to the The upper side 20b of the leaf spring member 20 is displaced to approach the lower side 20a via a chit 25 at the end. In order to detect all of this displacement, the tip VC of the lower side 20a is connected to a contact type detection switch 21.
is provided on the tip of the upper side 20b, and this upper side 2
When the tip of 0b is displaced, the detection switch 21 'kO
It is configured as an operating end 26 for N. Also,
In order to restrict the entire displacement of the VJ end 26 to a constant range, a planar stopper 21 is provided upright on the inner side of the lower side 208 and is concentric with the rod 17. Furthermore, both sides 2 of the temporary spring member 20
In Qa, 2 (JbVC, a spring constant adjusting member 30 consisting of a bolt 28 and a nut 29 is provided across the hook, and by adjusting the screws of these bolts 28 and nuts 29, the leaf spring member 20
The spring constant can be fully variable.

According to the above configuration, the driver's seat -
When the inner cable 12t is pulled from c, the tensile force is transmitted to the plate spring member 6 via the nut 25 on the rod 11 and the leaf spring member 20, and first this
Place it in X position. This is lCL, Tsuku-.

King brake 2 is braked. Further, by increasing the tensile force, when the tensile force exceeds all the spring legs of the leaf spring member 20, the upper side 20b of the leaf spring member 20 is displaced, and the operating end 26 of the leaf spring member 20 turns on all of the detection switches 21. Become. As a result, it is possible to completely detect that the king brake 2 has been operated. In particular, since the sensor 14't is provided directly on the brake lever member 6, it is not affected by the cable efficiency, and therefore the sensor 14't is not affected by the cable efficiency, and therefore the sensor 14't is not affected by the cable efficiency.
Doesn't the pulling force become heavy and the operability is the same? can be achieved. Further, unlike the case where a sensor is provided in the middle of the cable, the present invention can be easily implemented in an existing R-king brake without making any changes except for the brake arm member 6. The structure of the sensor 14' is also simplified and lightened because the leaf spring member 20 is fully assembled, and the influence of the load on the brake lever member 6 is extremely small, as well as cost reduction. can.

Furthermore, since the leaf spring member 207 is seated on the spherical catch 19 formed on the sound B material 6, and the rod 1T is connected to the tip of the inner cable 12,
The strength of the tensile force acting on the inner cable 12 and the direction of the pressing force applied to the leaf spring member 20 always match, and it is possible to obtain the accuracy of detection.

[Modified example of the invention]

In the embodiment described above, the connecting member is constituted by the cable 10, but it may be constituted by a link.

The spring constant adjusting member 30 may also be constructed by laminating a plurality of thin plates 31 to form the springing material 20, as shown in FIG. 5, and depending on the number of thin plates 310. This will change the constant. Furthermore, a mounting plate 32 is attached to the T side 20a of the plate spring member 20 as shown in FIG.
The detection switch 21 may be attached through a screw, and the detection switch 21 may have a screw-fastened structure so that the gap 33 between the detection switch 21 and the operating end 26 can be adjusted.

7 and 8 respectively show the case where the sensor 14' is provided on the tension side of the seven brake lever member 6. The one shown in FIG. 7 is of a type in which the plate spring member 20 is fully compressed and its displacement is fully detected.
4 passes through the upper side 20bt of the plate spring member 20 and is locked to the lower side 21]a, and the inner cable 1
The second rod 1T completely penetrates the lower side 20a and is locked to the upper side 20b. The upper end of the mounting rod 34 is inserted into the through hole 18 of the gray repair member 6, and a spherical nut 35 seated on the spherical seat 19 is screwed thereto. On the other hand, the one shown in FIG. 8 is a type in which the leaf spring member 20 is expanded and its displacement is detected.
The upper side 20bF (: rJ, the lower end of the mounting rod 34 is
The upper end of the rod 11 is locked to the lower side '1QaK, and the detection switch 21 is one that is activated when the operating end 26 is released. In addition, in order to restrict the expansion displacement k of the operating end 26 to a certain range, the operating end 26 is
A stone 4-36 that engages with the hJ side 20b is provided. [Effects of the Invention] In summary, the present invention provides the following advantages.

(1) Since a load detection means consisting of a leaf spring member and a detection switch is provided on one member of the 7'lz lever, the structure is simple and different from the existing structure, unlike the conventional structure provided in the middle of the cable. - Extremely easy to install without major modifications to the king brake.

(2) In addition, the load detection means is located on the output side of the connecting member such as a cable, and the setting value of the spring constant of the leaf spring member does not necessarily take into account the tensile efficiency of the connecting member. It reduces pulling force and improves operability.

(3) Since a leaf spring member is used, the structure can be further reduced in size and weight, and costs can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a schematic side view showing the cable wiring state of the parking brake, Fig. 2 is a sectional view showing the general internal structure of the e-king brake, Fig. 3 is a configuration diagram of a conventional bulking brake device, FIG. 4 is a partially cutaway side view of a parking brake device showing a preferred embodiment of the present invention, FIGS. 5 to 8 show different modifications of the present invention, and FIG. 5 is a side view of a temporary spring member. 6 to 8 are partially cutaway side views. In the figure, 2 is a parking brake, 6 is a brake lever member, 7 is an operating lever member, 10 is a cable as a connecting member, 20 is a plate spring member, 21 is a detection switch, and 26 is an operating end. Patent Applicant Ichoso Jidosha Co., Ltd. Agent Patent Attorney Nobuo Kinutani $4 required

Claims (1)

[Scope of Claims] l) A swingable brake lever member is provided for driving the parking brake, which is driven by the entire drive system, and an operating lever member is provided on the driver's seat side, and the operating lever member is provided with an operating lever member on the driver's seat side. In a parking brake device in which the force side of the brake lever member and the VC connecting member are engaged, the brake lever member applies braking force to the brake on the force side of the brake lever member. One end of the leaf spring member is formed into a U-shape and has a spring constant greater than the maximum load required for A parking brake device characterized in that a detection switch is provided between both ends of the leaf spring member to connect the road portions of the connection member as described above, and to detect displacement thereof. 2) The semi-king brake device according to claim 1, wherein one end of the plate spring member constitutes an operating end for actuating the detection switch.