JP5050068B2 - Parking brake device - Google Patents

Description

  The present invention relates to a parking brake device used for parking braking of an automobile, and relates to a technique for realizing easy and reliable operation while adopting a compact lever unit.

  Parking brakes used for parking braking for automobiles consist of a lever unit installed in the driver's seat, a parking brake drum built into the left and right rear wheels, a brake cable that transmits the operation of the lever unit to both parking brake drums, etc. ing. As a lever unit, there is a manual type that the driver manually holds and lifts the brake lever (or pulls it forward) (refer to Patent Document 1), but the driver gives a large operating force. For the purpose of facilitating, etc., the number of foot pedals in which a driver steps on the brake pedal with his / her foot is increasing (see Patent Documents 2 and 3).

  The foot-operated lever unit of Patent Documents 2 and 3 is composed of a base fixed to the vehicle body (dash panel, etc.), a brake pedal (brake lever) supported swingably on the base via a lever pivot, etc. Has been. The brake cable consists of an outer cable, one end of which is fixed to the base, and an inner cable, one end of which is supported by the brake pedal via a cable pivot. When the brake pedal is depressed, the inner cable is pulled out of the outer cable. It is. A cable guide having a curved guide portion is formed integrally with the brake pedal, and an inner cable is wound around the guide portion of the cable guide.

  In this type of foot-operated parking brake, the lever ratio (the pedal depression amount and the inner cable) is changed according to the depression angle of the brake pedal by changing the positional relationship between the cable guide and the lever pivot and the curvature of the guide portion. (Ratio with the amount of drawer) can be set freely. Normally, in foot-operated parking brakes, the inner cable is pulled out faster by reducing the lever ratio at the beginning of depression (in the range where there is no brake shoe play in the parking brake drum), and at the end of depression ( By increasing the lever ratio (in the range where braking is actually started), the inner cable is pulled out slowly (that is, the tensile force is increased).

JP 2007-62578 A Japanese Patent Laid-Open No. 2005-324581 JP 2009-101767 A

  However, since the conventional foot-operated parking brake employs a structure in which the inner cable is always wound around the guide portion of the cable guide, a large cable guide is required to sufficiently pull out the inner cable in the initial step. Become. As the cable guide becomes larger, the brake lever and the base naturally become larger, resulting in an increase in the size and weight of the lever unit and a reduction in the degree of freedom in layout around the driver's seat. It is possible to eliminate the cable guide and pull out the inner cable directly with the cable pivot. However, in this case, the degree of freedom in setting the lever ratio is extremely small (that is, the lever ratio depends on the lever pivot and the cable pivot). Therefore, for example, the amount of inner cable pulled out at the end of depression is very small, and there is a possibility that parking braking with sufficient braking force cannot be performed.

  The present invention has been made in view of such a background, and an object thereof is to provide a parking brake device that realizes an easy and reliable operation while employing a compact lever unit.

A first aspect of the present invention is a parking brake device mounted on a vehicle, a base fixed to the vehicle body, a brake lever supported on the base so as to be swingable and swinging within a predetermined angle range from an initial position, A brake cable in which one end of the outer cable is fixed to the vehicle body side, and one end of the inner cable is supported on the brake lever; a cable guide provided on the brake lever and having a substantially arc shape around which the inner cable is wound; The inner cable is separated from the cable guide at the initial position, contacts the cable guide when the brake lever swings to a predetermined winding start angle, and the brake lever wound around the cable guide to swing beyond the hanging start angle, the brake lever before A first straight line connecting the lever pivot and one end of the outer cable, the lever pivot and the cable supported by the base via a lever pivot; the inner cable supported by the brake lever via a cable pivot; The angle of intersection with the second straight line connecting the pivot increases as the brake lever swings from the initial position, the center of the cable guide and the center of the lever pivot are offset, and the cable guide The winding length of the inner cable gradually increases with respect to the swing amount of the brake lever at the end of the swing range of the brake lever .

The second invention is a parking brake device mounted on a vehicle, wherein the base is fixed to the vehicle body, and the brake is swingably supported by the base and swings within a predetermined angular range from the initial position. A lever, an equalizer connected to one end of each of the left and right rear brake cables, a brake cable supported at one end by the brake lever and connected at the other end to the equalizer, and the brake lever. A cable guide having a substantially arc shape to be wound, wherein the brake cable is separated from the cable guide at the initial position, and when the brake lever swings to a predetermined winding start angle, the cable When the brake lever comes into contact with the guide and swings beyond the winding start angle, The brake lever is supported on the base via a lever pivot, the brake cable is supported on the brake lever via a cable pivot, and the lever pivot and the outer cable of the left and right rear brake cables An angle of intersection between a first straight line connecting one end of the cable and a second straight line connecting the lever pivot and the cable pivot increases as the brake lever swings from the initial position. The center of the lever is offset from the center of the lever pivot, and at the end of the swing range of the brake lever, the cable guide gradually increases the winding length of the brake cable with respect to the swing amount of the brake lever. And

According to the first and second inventions, the inner cable (brake cable) is directly pulled out by the brake lever at the initial stage of swinging of the brake lever, and is pulled through the cable guide at the end of swinging. An appropriate lever ratio can be set without unnecessarily increasing the guide, and the inner cable (brake cable) can be pulled smoothly at the end of the swing. Further, since the lever ratio increases as the brake lever swings, a natural operation feeling is realized. Further, since the pulling amount of the inner cable (brake cable) increases at the end of the swing of the brake lever, parking braking by the parking brake is performed more reliably.

It is a principal part perspective view which shows the lever unit which concerns on 1st Embodiment. It is a side view which shows a lever unit in the state which removed the left base plate. It is a side view which shows a ratchet mechanism. It is operation | movement explanatory drawing of a ratchet mechanism. It is a figure which shows the relationship between the brake pedal and an inner cable in the step-down initial stage. It is a figure which shows the relationship between the brake pedal and an inner cable in the depression final stage. It is a graph which shows the relationship between a pedal stroke and a lever ratio. It is a perspective view which shows the lever unit which concerns on 2nd Embodiment. It is a side view which shows the lever unit which concerns on 2nd Embodiment.

  Hereinafter, two embodiments in which the present invention is applied to a parking brake device for a passenger car will be described in detail with reference to the drawings. In the description of the first embodiment, the left side in FIG. 2 is the front side, and the front side of the paper is the left side. In the description of the second embodiment, the right side in FIG. 2 is the front side, and the front side of the drawing is the right side.

[First Embodiment]
<< Configuration of First Embodiment >>
<Overall structure of lever unit>
In the first embodiment, the present invention is applied to a foot-operated parking brake device. As shown in FIGS. 1 and 2, the lever unit 1 according to the first embodiment includes a base 2, a brake pedal 3, a return spring 4, and a ratchet mechanism 5 as main components. The brake cable 6 is driven in response to the depression of 3.

  The base 2 is composed of a left base plate 21 and a right base plate 22, both of which are steel plate press-formed products, and a front end portion is fastened to the dash panel 10. In the drawing, a member denoted by reference numeral 23 is a pedal stopper that also serves as a distance collar and is interposed on the rear end side of both base plates 21 and 22, and a member denoted by reference numeral 8 is a parking brake switch attached to the upper end of the left base plate 21. It is.

  The brake pedal 3 includes a left pedal plate 31 and a right pedal plate 32, both of which are steel plate press-formed products, and is supported between the base plates 21 and 22 via a pedal pivot 33 so as to be swingable. In the figure, a member denoted by reference numeral 34 is a pedal pad (toe pad) attached to the lower end of the brake pedal 3.

  The return spring 4 is a tension coil spring spanned between the upper front end of the brake pedal 3 and the front portion of the left base plate 21, and biasing force in the return direction (left rotation direction in FIG. 2) with respect to the brake pedal 3. Is always giving.

  The ratchet mechanism 5 includes a ratchet plate 51 fixed to the left base plate 21 by a pair of front and rear rivets 51a and 51b, a ratchet pawl 52 incorporated in the brake pedal 3, and the brake pedal 3 depressed by the driver. Is held at that angle. The ratchet plate 51 is disposed between the left pedal plate 31 and the right pedal plate 32. Both rivets 51 a and 51 b are caulked to the left base plate 21 so as to straddle the left pedal plate 31.

  The brake cable 6 includes an outer cable 61 and an inner cable 62. One end 61 a of the outer cable 61 is fastened to the left side surface of the right base plate 22, while one end 62 a of the inner cable 62 is connected to the upper end of the brake pedal 3. The pivot pin 35 is pivotably connected. Although not shown, the other end of the inner cable 62 is connected to a rear brake cable for driving the left and right rear wheel brake drums via an equalizer mechanism.

<Brake pedal>
In the case of the brake pedal 3 of the first embodiment, both pedal plates 31 and 32 are joined / integrated by spot welding (or rivet), but in order to receive the inner cable 62 when the brake pedal 3 is depressed, The front part is separated by a predetermined gap. Further, the front joint edges (indicated by broken lines in FIG. 2) of the pedal plates 31 and 32 indicate the state in which the brake pedal 3 is most depressed by a two-dot chain line in FIG. The cable guide 36 has a substantially arc shape so that the inner cable 62 is wound around the cable. The center Ccg of the cable guide 36 is offset forward with respect to the center Clp of the pedal pivot 33 so that the winding length of the inner cable 62 is gradually increased at the end of the depression of the brake pedal 3.

  The right pedal plate 32 forms the main body of the brake pedal 3 and extends from the support portion of the inner cable 62 to the pedal pad 34. The left pedal plate 31 has an upper end extending to a support portion of the inner cable 62 in the same manner as the right pedal plate 32, while a lower end is cut off below the ratchet mechanism 5. The left pedal plate 31 is narrowed in the front-rear width of a portion 31a that overlaps the ratchet plate 51 in a side view so as not to interfere with both rivets 51a and 51b in the swing range of the brake pedal 3.

<Inner cable>
As shown by a solid line in FIG. 2, the inner cable 62 is separated from the cable guide 36 by a distance a in an initial state where the brake pedal 3 is not depressed, but as shown by a two-dot chain line in FIG. In the braking state in which the brake pedal 3 is depressed, the cable guide 36 is wound. An intersection angle θ between a straight line L1 connecting the center Clp of the pedal pivot 33 and one end Cuc of the outer cable 61 and a straight line L2 connecting the center Clp of the pedal pivot 33 and the center Cpp of the pivot pin 35 is an obtuse angle in the initial state. It increases as the brake pedal 3 is depressed.

<Ratchet mechanism>
As shown in FIG. 3, the ratchet mechanism 5 includes a turnover spanned between the ratchet plate 51 and the ratchet pole 52, a stopper plate 53 integral with the ratchet pole 52, and the left pedal plate 31 and the ratchet pole 52. A spring 54, a support pin 37 fixed to the brake pedal 3, and the like are included. The stopper plate 53 has a long hole 53 a into which the support pin 37 is loosely fitted, and changes the swing fulcrum of the ratchet pole 52 according to the depression state of the brake pedal 3.

  When the driver depresses the brake pedal 3 when the automobile is stopped, the ratchet pawl 52 biased by the turnover spring 54 engages with the ratchet teeth 51c of the ratchet plate 51 as shown in FIG. The return of the pedal 3 is prevented. At this time, when the stopper plate 53 moves downward with respect to the support pin 37, the turnover spring 54 reverses and urges the ratchet pole 52 in the opening direction. On the other hand, when the driver depresses the brake pedal 3 again at the start of the automobile, the ratchet pole 52 urged by the turnover spring 54 is separated from the ratchet plate 51 as shown in FIG. By releasing the pedal effort, the brake pedal 3 biased by the return spring 4 (see FIGS. 1 and 2) swings in the return direction. When the brake pedal 3 returns to the initial position, as shown in FIG. 4C, the stopper plate 53 (that is, the ratchet pawl 52) collides with the protrusion of the ratchet plate 51 and rotates, and the turnover spring 54 is reversed again. By doing so, the ratchet pole 52 is urged in the engaging direction.

<< Operation of First Embodiment >>
<Change in lever ratio>
When the driver parks the vehicle and depresses the brake pedal 3, the pivot pin 35 pivots around the pedal pivot 33, as shown in FIG. 5, and the inner cable 62 is pulled out from the outer cable 61 while moving backward. It swings (rightward in FIG. 5). At this time, since the intersection angle θ is an obtuse angle in the initial state and becomes larger as the brake pedal 3 is depressed, the lever ratio (ratio between the amount of depression of the brake pedal 3 and the amount of extension of the inner cable 62) is gradually increased. Increase.

  When the driver further depresses the brake pedal 3, as shown in FIG. 6, the inner cable 62 is wound around the cable guide 36 after contacting the cable guide 36. In the case of the first embodiment, as shown in FIG. 7, the lever ratio increases until the inner cable 62 comes into contact with the cable guide 36, but when the inner cable 62 starts to be wound around the cable guide 36 (winding). It starts to gradually decrease from the starting point.

  The lever unit 1 according to the first embodiment employs the above-described configuration, so that it is possible to realize an easy and reliable operation while having a relatively small brake pedal 3. That is, when the brake pedal 3 is initially depressed, the operability is improved because the amount of the inner cable 62 pulled out is large. In addition, since the amount of pulling out of the inner cable 62 is small (ie, the tensile force is high) in the middle of the depression of the brake pedal 3, a sufficient parking braking force is ensured. Then, at the end of the depression of the brake pedal 3, the amount of the inner cable 62 pulled out becomes larger than that in the middle of the depression (because the increase in the lever ratio is suppressed), so that reliable parking braking is realized.

<Brake pedal rigidity / strength>
In the case of the first embodiment, the brake pedal 3 is obtained by joining the left pedal plate 31 and the right pedal plate 32, and the ratchet plate 51 is disposed between the pedal plates 31, 32. Due to the force acting on the brake pedal 3, no lateral force or twisting force acts on the brake pedal 3, and a smooth braking operation is realized.

  Further, since the ratchet plate 51 is fixed only to the left base plate 21 and the front-rear width of the portion 31a overlapping the ratchet plate 51 of the left pedal plate 31 in a side view is narrowed, the right pedal plate 32 (that is, the brake pedal 3) The overall length of the ratchet plate 51 can be reduced while adopting a relatively large one having sufficient strength and rigidity, and the base 2 (that is, the lever unit 1) can be reduced in size and weight. . The right pedal plate 32 overlaps the rear rivet 51b in a side view at the initial position of the brake pedal 3, but is separated from the head of the rear rivet 51b by a predetermined distance in the left-right direction.

[Second Embodiment]
<< Configuration of Second Embodiment >>
In the second embodiment, the present invention is applied to a manual parking brake device. As shown in FIG. 8, the lever unit 71 of the second embodiment includes a base 72, a brake lever 73, and a ratchet mechanism (not shown) as main components, and the driver can lift the brake lever 73. Accordingly, the brake cable 74 is driven.

  The brake cable 74 is pivotally connected to the lower portion of the brake lever 73 via a pivot pin 80 and has a rear end coupled to an equalizer 83 via an adjuster 81 and an equalizer pin 82. When the brake lever 73 is pulled up, the brake cable 74 is pulled forward, and the inner cables 93 and 94 of the left and right rear brake cables 91 and 92 whose respective ends are swingably supported by the equalizer 83 are pulled out. In FIG. 8, a member indicated by reference numeral 75 is a release knob, and a member indicated by reference numeral 97 is a cable base guide for fixing the outer cables 95 and 96 of the left and right rear brake cables 91 and 92 to the vehicle body.

  The brake lever 73 is swingably supported on the base 72 via a lever pivot 76, and a cable guide 77 similar to that of the first embodiment is integrally formed at a lower portion thereof. As shown by a solid line in FIG. 8, the brake cable 74 is separated from the cable guide 77 by a distance b in an initial state where the brake lever 73 is not lifted, but as shown by a two-dot chain line in FIG. In the braking state in which the brake lever 73 is pulled up, the cable guide 77 is wound.

  As shown in FIG. 8, an intersection angle between a straight line L3 connecting the center Clp of the lever pivot 76 and one ends Cuc of the outer cables 95 and 96 and a straight line L4 connecting the center Clp of the lever pivot 76 and the center Cpp of the pivot pin 80. θ is an obtuse angle in the initial state, and increases as the brake lever 73 is pulled up. Since the crossing angle θ is an obtuse angle in the initial state and increases as the brake lever 73 is lifted, the lever ratio (ratio between the pulling amount of the brake lever 73 and the pulling amount of the brake cable 74) gradually increases. .

<< Operation of Second Embodiment >>
The lever unit 71 of the second embodiment is also a compact one having a relatively small brake lever 73, as in the second embodiment described above, but can realize an easy and reliable operation. That is, in the initial stage of raising the brake lever 73, the pulling amount of the brake cable 74 is increased, so that operability is improved. Further, during the middle period of raising the brake lever 73, the pulling amount of the brake cable 74 becomes small (that is, the tensile force becomes high), so that a sufficient parking braking force is ensured. Then, at the end of lifting of the brake lever 73, the amount of pulling of the brake cable 74 becomes larger than that in the middle of lifting (because the increase in the lever ratio is suppressed), so that reliable parking braking is realized.

  Although the description of the specific embodiments is finished as described above, the present invention is not limited to these embodiments and can be widely modified. For example, in the above-described embodiment, the present invention is applied to a foot-operated parking brake, but the present invention is naturally applicable to a manual parking brake. In the above embodiment, the cable guide is formed at the joint edge of the left and right pedal plates. However, a separate cable guide may be fixed to the left pedal plate or the right pedal plate, or the cable guide may be rotated on the base. You may make it support freely. In the above embodiment, a substantially arc-shaped cable guide is used. However, a cable guide having a combination of a plurality of curves and straight lines may be used to optimize the lever ratio. In addition, the specific configuration and the like of the base and the ratchet mechanism can be changed as appropriate without departing from the spirit of the present invention.

1 Lever unit 2 Base 3 Brake pedal (brake lever)
4 Return spring 5 Ratchet mechanism 6 Brake cable 33 Pedal pivot (lever pivot)
35 Pivot Pin 36 Cable Guide 61 Outer Cable 62 Inner Cable 71 Lever Unit 72 Base 73 Brake Lever 74 Brake Cable 76 Lever Pivot 77 Cable Guide 81 Adjuster 83 Equalizer 91 Left Rear Brake Cable 92 Right Rear Brake Cable 95 Outer Cable 96 Outer Cable

Claims (2)

A parking brake device mounted on a vehicle,
A base fixed to the vehicle body,
A brake lever that is swingably supported by the base and swings within a predetermined angle range from an initial position;
One end of the outer cable is fixed to the vehicle body, and one end of the inner cable is supported by the brake lever.
A cable guide provided in the brake lever and having a substantially arc shape around which the inner cable is wound;
The inner cable is
Spaced apart from the cable guide at the initial position;
When the brake lever swings to a predetermined winding start angle, it contacts the cable guide,
When the brake lever swings beyond the winding start angle, it is wound around the cable guide ,
The brake lever is supported on the base via a lever pivot;
The inner cable is supported by the brake lever via a cable pivot;
The intersection angle between the first straight line connecting the lever pivot and one end of the outer cable and the second straight line connecting the lever pivot and the cable pivot is as the brake lever swings from the initial position. And grow
The center of the cable guide and the center of the lever pivot are offset,
The parking brake device according to claim 1, wherein the cable guide gradually increases a winding length of the inner cable with respect to a swing amount of the brake lever at an end of a swing range of the brake lever . A parking brake device mounted on a vehicle,
A base fixed to the vehicle body,
A brake lever that is swingably supported by the base and swings within a predetermined angle range from an initial position;
An equalizer in which one end of each of the left and right rear brake cables is connected,
A brake cable having one end supported by the brake lever and the other end connected to the equalizer;
A cable guide provided on the brake lever and having a substantially arc shape around which the brake cable is wound;
The brake cable is
Spaced apart from the cable guide at the initial position;
When the brake lever swings to a predetermined winding start angle, it contacts the cable guide,
When the brake lever swings beyond the winding start angle, it is wound around the cable guide,
The brake lever is supported on the base via a lever pivot;
The brake cable is supported by the brake lever via a cable pivot;
The angle of intersection between the first straight line connecting the lever pivot and one end of the outer cable of the left and right rear brake cables and the second straight line connecting the lever pivot and the cable pivot is determined by the brake lever from the initial position. As you swing,
The center of the cable guide and the center of the lever pivot are offset,
The parking brake device, wherein the cable guide gradually increases a winding length of the brake cable with respect to a swing amount of the brake lever at an end of a swing range of the brake lever.

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