JP3591717B2 - Brake lock device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a brake lock device that is used in combination with a parking brake when a vehicle is stopped while an engine is operating, such as a construction work vehicle, to perform work.
[0002]
[Prior art]
Conventionally, this type of brake lock device includes a brake lock actuating device having a brake lock relay, a brake lock manual valve, and the like, and a brake lock detecting device. The brake lock relay operates the manual brake lock valve via the solenoid based on the detection output to communicate the brake pedal with the wheel brakes of each wheel, and simultaneously activates the brake lock provided in the driver's seat. It is known that when the preparation lamp is turned on and the occupant operates the brake lock manual valve with the brake pedal depressed further, the brake lock manual valve closes and the wheel brake fluid pressure is maintained. I have.
[0003]
For example, one end of a first member of the brake lock detecting means is pivotally connected to a parking brake lever via a first shaft, and one end of a second member is rotatably attached to a cable via a second shaft. A brake lock device in which two compression coil springs for urging the shaft and the second shaft so as to be relatively close to each other is interposed between the first member and the second member, and further provided with a detection switch on the first member. It has been disclosed (Japanese Utility Model Laid-Open No. 5-40070).
In the brake lock device configured as described above, the parking brake lever is operated with a force equal to or greater than a predetermined value, and the first shaft and the second shaft relatively move away from each other against the elastic force of the two compression coil springs. Is moved by a predetermined distance, the detection switch is switched, and the brake lock operating means is enabled.
[0004]
[Problems to be solved by the invention]
However, in the conventional brake lock device disclosed in Japanese Unexamined Utility Model Publication No. Hei. 5-40070, two compression coil springs are used for the brake lock detecting means, so that a space for accommodating the brake lock detecting means is required. There was a problem that had to be secured relatively large.
An object of the present invention is to provide a brake lock device in which the number of elastic bodies of the brake lock detecting means can be reduced from two to one, whereby the brake lock detecting means can be accommodated in a relatively small space. .
[0005]
[Means for Solving the Problems]
As shown in FIG. 1, the invention according to claim 1 includes a parking brake lever 11 provided in a driver's seat of a vehicle to activate or deactivate a parking brake via a cable 13 when operated by an occupant; A brake lock operating means operable by operating the motor 11 with a force equal to or greater than a predetermined value; and a brake lock detecting means 12 for detecting whether the brake lock operating means is in an operable state. It is an improvement.
The characteristic configuration is that the brake lock detecting means 12 includes first and second links 21 and 22 each having one end pivotally connected to the lever 11 via a first shaft 31 and one end via a second shaft 32. Third and fourth links 23 and 24 respectively rotatably attached to the cable 13, and a third shaft 33 for rotatably connecting the other end of the first link 21 and the other end of the third link 23. A fourth shaft 34 that connects the other end of the second link 22 and the other end of the fourth link 24 so as to be relatively rotatable; and a third and a fourth shaft 33, 34 interposed between the third and fourth shafts 33 and 34. A single elastic body 17 for urging the fourth shafts 33 and 34 away from each other and biasing the first and second shafts 31 and 32 toward each other, and attached to a stay 24 a protruding from one end of the fourth link 24. The lever 11 is operated with a force equal to or greater than a predetermined value, and the first shaft 31 is 32 there is to have a switching switched detection switch 18 away from the third link 23 when moving distance in a direction away against the elastic force of a predetermined elastic member 17.
[0006]
In the brake lock device according to the first aspect, the parking brake lever 11 is operated with a force equal to or more than a predetermined value, and the first shaft 31 is moved from the second shaft 32 against the elastic force of the single elastic body 17. away when moved by a predetermined distance in the direction, switched away from the third link 23 is detecting switch 18, the brake lock operation unit is set to be in the activation state. Further, the single elastic body 17 of the brake lock detecting means 12 can generate the same elastic force as two conventional elastic bodies, and only one elastic body 17 is required. Can be accommodated in small spaces.
[0007]
In the invention according to claim 2, as shown in FIG. 7, the brake lock detecting means 52 includes first and second links 21 and 22 each having one end pivotally connected to the lever 51 via the first shaft 31. The third and fourth links 53 and 54, one ends of which are rotatably attached to the cable 13 via the second shaft 32, and the other end of the first link 21 and the other end of the third link 53 are relatively rotated. And a third shaft 33 that connects the other end of the second link 22 and the other end of the fourth link 54 so as to be relatively rotatable. A single elastic body 17 interposed therebetween for biasing the third and fourth shafts 33 and 34 away from each other and urging the first and second shafts 31 and 32 toward each other; The lever 51 is attached to the protruding stay 53a, the lever 51 is operated with a force of a predetermined value or more, and Characterized in that one axis 31 and a detection switch 18 which switches off the fourth link 54 when moved by a predetermined distance in a direction away against the elastic force of the elastic body 17 from the second shaft 32 .
[0008]
In the brake lock device according to the second aspect, the parking brake lever 51 is operated with a force of a predetermined value or more, and the first shaft 31 is opposed to the elastic force of the single elastic body 17 from the second shaft 32. away when moved by a predetermined distance in the direction, switched away from the fourth link 54 is detecting switch 18, the brake lock operation unit is set to be in the activation state. Further, the single elastic body 17 of the brake lock detecting means 52 can generate the same elastic force as two conventional elastic bodies, and the brake lock detecting means 52 can be accommodated in a smaller space than before.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, a first embodiment of the present invention will be described with reference to the drawings.
As shown in FIGS. 1 to 3, a parking brake lever 11 is provided in the driver's seat of the vehicle, and the parking brake lever 11 is provided on a main shaft of the transmission via a brake lock detecting means 12 and a cable 13. (Not shown). The lever 11 includes a bracket 11a fixed to the floor panel 14, a lever main body 11c having a base end pivotally connected to the bracket 11a via a shaft 11b, and an operating section 11d provided at a distal end of the lever main body 11c and operated by an occupant. Having. The brake lock detecting means 12 is attached to the four-link mechanism 16 provided between the lever 11 and the cable 13, a single elastic body 17 interposed in the link mechanism 16, and attached to the link mechanism 16. And a detection switch 18.
[0010]
The link mechanism 16 is provided on the first to fourth links 21 to 24, the first to fourth shafts 31 to 34, the stay 24 a protruding from one end of the fourth link 24, and the third link 23. And a stopper 23a. One ends of the first and second links 21 and 22 are respectively pivotally connected to the lever 11 via the first shaft 31. That is, the first shaft 31 is mounted near the base end of the lever 11, and one ends of the first and second links 21 and 22 are rotatably mounted on the first shaft 31 respectively. One end of each of the third and fourth links 23 and 24 is rotatably attached to the cable 13 via the second shaft 32. That is, the second shaft 32 is attached to the base end of the cable 13, and one ends of the third and fourth links 23 and 24 are attached to the second shaft 32 so as to be rotatable. The other end of the first link 21 and the other end of the third link 23 are relatively rotatably connected by a third shaft 33, and the other end of the second link 22 and the other end of the fourth link 24 are connected to a fourth shaft. 34 are connected so as to be relatively rotatable. The first shaft 31 among the first to fourth shafts 31 to 34 is attached to the lever main body 11d, and is configured to rotate together with the lever main body 11d. On the other hand, the second to fourth shafts 32 to 34 are not attached to any of the lever body 11d, the bracket 11a, and the floor panel 14, and are configured to be relatively movable with respect to the lever body 11d and the like.
[0011]
The elastic body 17 is a compression coil spring in this embodiment, and is interposed between the third and fourth shafts 33 and 34 as shown in detail in FIGS. A rod 26 for preventing the spring from dropping is loosely inserted into the compression coil spring 17. A pair of male screw portions 26a, 26a protrude from both ends of the rod 26, and through holes 33a, 34a through which the male screw portions 26a, 26a can be inserted are formed in the third and fourth shafts 33, 34, respectively. . After a pair of male screw portions 26a, 26a at both ends of the rod 26 are inserted into the through holes 33a, 34a of the third and fourth shafts 33, 34, nuts are respectively inserted into the male screw portions 26a, 26a protruding from the through holes 33a, 34a. 27, 27 are screwed two by two. The nut 27 is fixed so that the third and fourth shafts 33 and 34 can approach each other by a predetermined distance, that is, from the position of FIG. 4 to the position of FIG. The compression coil spring 17 biases the third and fourth shafts 33 and 34 away from each other and the first and second shafts 31 and 32 toward each other.
[0012]
The detection switch 18 is attached to a stay 24a protruding from one end of the fourth link 24. The detection switch 18 has a case 18a and a plunger 18b that protrudes and retracts from the case 18a. The stopper 23a is provided at a position of the third link 23 facing the plunger 18b. When the operating portion 11d of the lever 11 is operated with a force less than a predetermined value, the distance between the first and second shafts 31 and 32 does not change, and the plunger 18b of the detection switch 18 is kept pressed into the case 18a. It is configured as follows. On the other hand, when the lever 11 is operated with a force equal to or greater than a predetermined value, the first shaft 31 moves by a predetermined distance in a direction away from the second shaft 32, and the plunger 18b of the detection switch 18 and the stopper 23a are separated, and the plunger 18b is moved. It is configured to protrude from the case 18a. The detection switch 18 is a switch having a break contact in this example, and is turned on when the plunger 18b protrudes from the case 18a, and turned off when the plunger 18b is pushed into the case 18a.
[0013]
The detection output of the detection switch 18 is connected to a brake lock relay of a brake lock operating means (not shown). The brake lock actuating means has the brake lock relay and the brake lock manual valve. Based on the detection output of the detection switch 18, the brake lock relay operates the brake lock manual valve via a solenoid to control the brake pedal and each wheel. The wheel brake is connected, and at the same time, a brake lock operation preparation lamp provided in the driver's seat is turned on. Also, in this state, when the occupant operates the brake lock manual valve by depressing the brake pedal, the brake lock manual valve is closed and the hydraulic pressure of the wheel brake is maintained. Reference numeral 28 in FIGS. 1 to 3 denotes a ratchet mechanism for fixing or releasing the lever 11 at a predetermined position. The ratchet mechanism 28 includes a ratchet wheel 28a formed on an upper portion of the bracket 11a and a lever 28. It has a claw 28b which is pivotally attached and detachably locked to the ratchet wheel 28a, and a push button 28d provided at the tip of the lever 11 to push the claws 28b away from the ratchet wheel 28a via a push rod 28c.
[0014]
The operation of the brake lock device thus configured will be described.
When the occupant operates the parking brake lever 11 in the direction of the solid line arrow in FIG. 2 with a force less than a predetermined value, the cable 13 is pulled in the direction of the broken line arrow via the link mechanism 16, and the lever 11 and the cable 13 of FIG. When the position shown by the solid line is reached, the parking brake (not shown) operates. At this time, the overall length of the compression coil spring 17 does not change, and the distance between the first and second shafts 31 and 32 does not change.
When the lever 11 is operated in the direction of the dashed-dotted arrow in FIG. 3 with a force greater than a predetermined value, the cable 13 is not pulled any further, so that the second shaft 32, that is, one end of the third and fourth links 23, 24 moves. do not do. As a result, the third and fourth shafts 33 and 34 move in a direction approaching each other against the elastic force of the compression coil spring 17, and the first shaft 31 moves a predetermined distance in a direction away from the second shaft 32. Therefore, the plunger 18b of the detection switch 18 attached to the stay 24a of the fourth link 24 is separated from the stopper 23a of the third link 23, and the detection switch 18 is turned on, so that the brake lock operating means is enabled.
[0015]
Here, the position of the lever 11 shown by the dashed line in FIG. 1 is the same as the position of the lever 11 shown in FIG. 2, the lever 11 is returned, the parking brake is not operated, and the brake lock operating means is The position is not ready for operation. The position of the lever 11 shown by the two-dot chain line in FIG. 1 is the same as the position of the lever 11 shown in FIG. 3, and although the lever 11 is operated with a force less than a predetermined value to operate the parking brake, It is a position where the lock operating means is not in the operable state.
[0016]
FIG. 7 shows a second embodiment of the present invention. 7, the same reference numerals as those in FIG. 1 indicate the same parts.
In this embodiment, a parking brake lever 51 is provided at a bracket 51a fixed to the floor panel 14, a base body 51c having a base end pivotally connected to the bracket 51a via a shaft 51b, and a distal end of the lever body 51c. An operating portion 51d operated by an occupant is provided, and the height of the bracket 51a is formed higher than that of the bracket of the first embodiment. As in the first embodiment, the brake lock detecting means 52 includes a four-node link mechanism 56 provided between the lever 51 and the cable 13 and a single compression coil interposed in the link mechanism 56. It has a spring 17 and a detection switch 18 attached to a link mechanism 56. A stay 53a for mounting the detection switch 18 is provided at one end of the third link 53 of the link mechanism 56, and a stopper 54a with which the plunger 18b of the detection switch 18 is detachably contacted is provided on the fourth link 54. Reference numeral 58a in FIG. 7 denotes a ratchet of a ratchet mechanism 58 for fixing or releasing the lever 51 at a predetermined position. Except for the above, the configuration is the same as that of the first embodiment.
[0017]
The operation of the brake lock device thus configured will be described.
When the occupant operates the parking brake lever 51 with a force less than a predetermined value, the cable 13 is pulled in the direction of the dashed arrow via the link mechanism 56, and the lever 51 and the cable 13 reach the position shown by the two-dot chain line, and the parking brake (Not shown) is activated. At this time, the overall length of the compression coil spring 17 does not change, and the distance between the first and second shafts 31 and 32 does not change.
If the lever 51 is operated with a force equal to or greater than a predetermined value, the cable 13 is not pulled any further, so that the second shaft 32, that is, one end of the third and fourth links 53 and 54 does not move. As a result, the third and fourth shafts 33 and 34 move in a direction approaching each other against the elastic force of the compression coil spring 17, and the first shaft 31 moves a predetermined distance in a direction away from the second shaft 32. Therefore, the plunger 18b of the detection switch 18 attached to the stay 53a of the third link 53 is separated from the stopper 54a of the fourth link 54, and the detection switch 18 is turned on, so that the brake lock operating means becomes operable. In this embodiment, although the height of the bracket 51a is higher than in the first embodiment, since the detection switch 18 is located near the bracket 51a, a cover (not shown) that covers the detection switch 18 and the link mechanism 56. Can be reduced.
[0018]
In the first and second embodiments, a compression coil spring is used as the elastic body. However, rubber, an air spring, or the like may be used as the elastic body.
[0019]
【The invention's effect】
As described above, according to the present invention, one ends of the first and second links of the brake lock detecting means are pivotally connected to the parking brake lever via the first shaft, and one ends of the third and fourth links are connected to the first and second links. The other ends of the first and third links are connected by a third axis, and the other ends of the second and fourth links are connected by a fourth axis. A single elastic body that biases the fourth shaft away from each other and biases the first and second shafts closer to each other is interposed between the third and fourth shafts, and is further provided at one end of the fourth link. Since the detection switch is attached to the stay, when the parking brake lever is operated with a force of a predetermined value or more and the first shaft moves a predetermined distance in a direction away from the second shaft against the elastic force of the elastic body. , it switches the detection switch is separated from the third link. As a result, the brake lock operating means is in an operable state. Further, the brake lock detecting means of the present invention can generate the same elastic force as two conventional elastic bodies even with one elastic body, and requires only one elastic body. Can be accommodated in space.
If a detection switch is attached to a stay protruding from one end of the third link, the parking brake lever is operated with a force of a predetermined value or more, and the first shaft is opposed to the elastic force of the elastic body from the second shaft. when moved by a predetermined distance away, it switches the detection switch is separated from the fourth link. As a result, the same effects as above can be obtained.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a main part including brake lock detection means showing a state in which a parking brake lever of a brake lock device according to a first embodiment of the present invention is operated with a force equal to or more than a predetermined value.
FIG. 2 is a cross-sectional view corresponding to FIG. 1, showing a state in which a parking brake lever is returned to a state where a parking brake is inactivated.
FIG. 3 is a cross-sectional view corresponding to FIG. 1, showing a state where the parking brake lever is operated with a force less than a predetermined value.
FIG. 4 is a sectional view taken along line AA of FIGS. 2 and 3;
FIG. 5 is a sectional view taken along line BB of FIG. 1;
FIG. 6 is a sectional view taken along line CC of FIG. 2;
FIG. 7 is a sectional view corresponding to FIG. 1, showing a brake lock device according to a second embodiment of the present invention;
[Explanation of symbols]
11, 51 parking brake lever 12, 52 brake lock detecting means 13 cable 17 compression coil spring (elastic body)
18 Detection switch 21 1st link 22 2nd link 23, 53 3rd link 24, 54 4th link 23a, 54a Stopper 24a, 53a Stay 31-34 1st-4th axis

Claims (2)

A parking brake lever (11) provided in the driver's seat of the vehicle to activate or deactivate the parking brake via a cable (13) when operated by an occupant; and operating the lever (11) with a force equal to or greater than a predetermined value. A brake lock actuating means operable by doing so, and a brake lock detecting means (12) for detecting whether the brake lock actuating means is in an operable state.
The brake lock detecting means (12)
First and second links (21, 22) each having one end pivotally connected to the lever (11) via a first shaft (31);
Third and fourth links (23, 24) each having one end rotatably attached to the cable (13) via a second shaft (32),
A third shaft (33) that connects the other end of the first link (21) and the other end of the third link (23) so as to be relatively rotatable;
A fourth shaft (34) connecting the other end of the second link (22) and the other end of the fourth link (24) so as to be relatively rotatable;
The third and fourth shafts (33, 34) are interposed between the third and fourth shafts (33, 34) to separate the third and fourth shafts (33, 34) from each other and to move the first and second shafts (31, 32) closer to each other. A single elastic body (17) for biasing,
The lever (11) is attached to a stay (24a) protruding from one end of the fourth link (24), the lever (11) is operated with a force equal to or greater than the predetermined value, and the first shaft (31) is moved to the second shaft (32). and characterized in that it has a switching switched detection switch (18) away from said elastic member (the when moved by a predetermined distance in a direction away against the elastic force of 17) third link (23) from) Brake lock device. A parking brake lever (51) provided in a driver's seat of a vehicle to activate or deactivate a parking brake via a cable (13) when operated by an occupant; and operating the lever (51) with a force equal to or greater than a predetermined value. A brake lock actuating means operable by doing so, and a brake lock detecting means (52) for detecting whether the brake lock actuating means is in an operable state,
The brake lock detection means (52)
First and second links (21, 22) each having one end pivotally connected to the lever (51) via a first shaft (31);
Third and fourth links (53, 54) each having one end rotatably attached to the cable (13) via a second shaft (32);
A third shaft (33) connecting the other end of the first link (21) and the other end of the third link (53) so as to be relatively rotatable;
A fourth shaft (34) connecting the other end of the second link (22) and the other end of the fourth link (54) so as to be relatively rotatable;
The third and fourth shafts (33, 34) are interposed between the third and fourth shafts (33, 34) to separate the third and fourth shafts (33, 34) from each other and bring the first and second shafts (31, 32) closer to each other. A single elastic body (17) biasing in the direction,
The lever (51) is attached to a stay (53a) protruding from one end of the third link (53), the lever (51) is operated with a force equal to or greater than the predetermined value, and the first shaft (31) is connected to the second shaft (32). and characterized in that it has a switching switched detection switch (18) away from said fourth link (54) when moved by a predetermined distance in a direction away against the elastic force of the elastic body (17) from) Brake lock device.

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