JPH0433173Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Field of Application> The present invention relates to a brake lock device for a motor vehicle, such as a mixer truck or a crane truck, which performs various operations while stopped.

<Prior art> Conventional brake lock devices installed to increase safety when working in a stopped state include:
For example, there is one described in Utility Model Publication No. 19088-1988. This is configured as shown in Fig. 5, with an air tank 01 and a brake valve 0.
By connecting the brake booster 03 and the air tank 01, which are connected through the brake booster 03 and the air tank 01, through the pressure reducing valve 04 and the brake locking solenoid valve 05, the parking brake switch 06 and the manual switch 0 can be connected.
7 is turned on, the brake locking solenoid valve 05 is opened and air reduced to a predetermined pressure is supplied to the booster 03, thereby controlling the service brake (wheel brake).
I am trying to operate 08. 09 is a double check valve, 010 is a relay, and 011 is a battery.

<Problems to be solved by the invention> However, in such a conventional example, it is necessary to provide an independent brake lock control system in addition to the normal brake control system, which increases the number of parts and makes the configuration complicated. There was a problem in that the weight increased as the weight increased.

The present invention was made to solve these conventional problems, and while suppressing the increase in parts,
The object of the present invention is to provide a brake lock device with a simple structure and high reliability that can achieve the intended purpose at a low cost.

<Means for solving the problem> In order to achieve the above object, the present invention provides a brake valve that controls the increase/decrease of the braking force of the service brake by changing the stroke of the plunger according to the amount of depression of the brake pedal. The plunger is provided with a piston that comes into contact with the plunger from the return direction of the plunger, and the chamber formed by the piston and the air tank are connected to a normally closed valve that is allowed to open only when the parking brake is operated. In an automobile brake lock device, which is connected via a manual valve and is provided with a return spring that slides and urges the piston in the return direction of the plunger, when the parking brake lever is operated to the operating position, and in addition to the parking brake, A control relay is provided that allows the manual valve to be opened only when the applied operating force is higher than a predetermined value, and at the same time activates the ready notification means. Further, a confirmation relay is provided that operates the lock confirmation notification means only when the pressure of the working fluid supplied to the service brake is higher than a predetermined value while the manual valve is operated to the operating position, and the manual valve is operated to the operating position. A warning means is provided which is activated when a drop in pressure of the working fluid occurs while the valve is being operated. The present invention is characterized in that the control relay and the confirmation relay are housed in the same relay box.

<Function> With this configuration, the service brake control system can also be used as a brake lock system, such that the brake valve normally operated by the brake pedal functions as a pressure reducing valve when the brake lock is activated. The increase in the number of parts can be suppressed to the necessary minimum, thereby suppressing increases in weight and cost. Furthermore, when the parking brake lever is reliably operated to the operating position and the operating force applied to the parking brake is higher than a predetermined value, that is, the parking brake is reliably operated according to the driver's will. It is possible to allow the manual valve to open only when the vehicle is in use, and at the same time to operate the preparation completion notification means to notify the driver that the preparation for the brake lock operation is complete. Furthermore, only when the manual valve is operated to the operating position and the pressure of the working fluid supplied to the service brake is higher than a predetermined value, the lock confirmation notification means is activated to confirm that the brake is reliably locked. If an oil leak occurs that prevents the brake from locking reliably despite operating the manual valve while notifying the driver, a warning means such as a warning buzzer will be activated. By warning the driver of this, it is possible to avoid various troubles due to erroneous operation, misidentification, failure, etc., and increase the reliability of the brake lock device. In addition, the control relay and confirmation relay are housed in the same relay box, reducing the number of electrical wiring outside the relay box and the number of connection points, making assembly work easier when mounting it on a car. In addition, maintenance and inspection workability can be improved.

<Embodiment> An embodiment of the present invention will be described in detail below with reference to FIGS. 1 to 4.

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention, in which a service brake (wheel brake) 3 is connected via a booster 2 to a brake valve 1 to which air is supplied from an air tank (not shown). . Reference numeral 4 denotes a brake pedal that controls the brake valve 1. By changing the amount of depression of the brake pedal 4, the hydraulic pressure supplied to the cylinder of the service brake 3 is adjusted, and the braking force of the service brake 3 is controlled to increase or decrease. Ru.

FIG. 2 shows the specific structure of the brake valve 1. In FIG. 2, a ring-shaped piston 6 is slidably fitted to the outer circumferential surface of a plunger 5 which is depressed by a brake pedal 4, and is formed at the lower end of the outer circumferential surface of the plunger 5. The lower end of the piston 6 is brought into contact with the upper surface of the stepped portion 7 from above. Therefore, air is supplied to the chamber 8 and the piston 6 is moved against the return spring 9.
When is pushed down in the figure, the plunger 5 is pushed down via the stepped portion 7.

The chamber 8 is connected to an air tank (not shown) via a normally closed manual valve 10, as shown in FIG. 11 is the primary piston,
12 is a secondary piston, 13 is a primary feed valve, 14 is a secondary feed valve, 15 is a main spring, 16, 17, 1
Reference numerals 8 and 19 indicate return springs, and since the basic structure and operation of the brake valve 1 are substantially the same as those of conventional brake valves, a detailed explanation thereof will be omitted.

3 and 4 show the specific structure of the manual valve 10, in which an air passageway is formed in a valve body 22 with an air inlet 20 connected to an air tank and an air outlet 21 connected to the chamber 8. It is connected via 23. Also, the air passage 23
A valve seat 24 is formed in the middle of the valve seat 24, and a valve body 25, which is seated on the valve seat 24 from the downstream side, is attached to the inner end of a rod 26 inserted into the valve body 22.

A knob 27 is fixed to the outer end of the rod 26, and the tip of a lock pin 29, which is operated to move in and out by a solenoid 28 fixed to the outside of the valve body 22, is attached to a groove 30 provided in the rod 26.
As a result, the locking pin 29 escapes from the groove 30 only when the solenoid 28 is energized, allowing the knob 27 to be pushed from the normal position to the locked position. Note that when the knob 27 is pushed in, the valve body 25 is opened. 31 is a return spring that biases the valve body 25 to close; 32
is a plunger that transmits the position of the valve body 25 to a position switch 33, and the position switch 33 is closed when the manual valve 10 is operated to open.

On the other hand, a contact (normally open contact) 36a of a control relay 36 and an operating force sensor 38 are interposed in series between the solenoid 28 attached to the manual valve 10 and a battery (not shown).

Here, the coil 36b of the control relay 36
is connected to the power source via a parking brake switch 35 that closes only when the parking brake lever 34 is operated to the operating position, as shown by the dashed line in FIG. 38 is closed (closed) only when the operating force acting on the parking brake 37 is higher than a predetermined value.

Therefore, when the parking brake lever 34 is reliably operated to the operating position and the operating force acting on the parking brake is higher than a predetermined value,
In other words, the solenoid 28 is energized and locks the lock pin 2 only when the parking brake is reliably applied.
9 escapes from the groove 30, thereby allowing the manual valve 10 to be opened. 39 is booster 2
The air pressure supplied to the brake valve 1
A pressure switch 40a is opened only when the pressure of the working fluid output from the service brake 3 to the service brake 3 is higher than a predetermined value, and 40a is the position switch 33.
and confirmation relay 4 connected to pressure switch 39
0 coil, 41 a warning buzzer connected in parallel to the coil 40a of the confirmation relay 40 to constitute a warning means, 42 a contact (normally closed contact) 40b of the confirmation relay 40 and the operating force sensor 38. This is an operation preparation lamp connected to a power source, and this operation preparation lamp 42 constitutes preparation completion notification means.

Further, the lock confirmation notification means for notifying that the brake lock device is operating reliably is constituted by a confirmation lamp 43, which is connected to the power source via the contact 40b of the confirmation relay 40 and the position switch 33. ing. 44 is an oil level switch, 45 is a stroke switch that closes when the stroke of the brake booster (not shown) is smaller than a predetermined value, 46 is a warning lamp, and 47 is a fuse, which is a terminal on the pressure switch 39 side of the warning buzzer 41. A diode 48 is interposed between the pressure switch side terminal of the coil 40b, and a warning buzzer 41 and the oil level switch 4
By interposing a diode 49 between the oil level switch 44 and the stroke switch 45, it is possible to prevent the warning lamp 46 from turning on due to the closing of the contact 40b of the confirmation relay 40, and also to prevent the warning lamp 46 from turning on when the contact 40b of the confirmation relay 40 is closed. 45 is closed, the coil 40a of the confirmation relay 40 is prevented from being inadvertently energized. Reference numeral 50 denotes a relay box that accommodates the control relay 36, confirmation relay 40, and diodes 48 and 49.

In the brake lock device constructed as described above, when the parking brake lever 34 is pulled up to the operating position, the parking brake switch 35 is closed, and the coil 36b of the control relay 36 is energized to close its contact 36a. Additionally, when the parking brake lever 34 is operated, the parking brake 37 is activated.
When the operating force acting on the sensor becomes higher than a predetermined value, the operating force sensor 38 is closed. Then, the solenoid 28 provided in the manual valve 10 is energized and the manual valve 10 is unlocked, and at the same time, the operation preparation lamp 42 lights up to notify the driver that the brake lock operation is possible. .

When the knob 27 of the manual valve 10 is pressed in this state, the position switch 33 is closed. Additionally, since the valve body 25 of the manual valve 10 is opened in conjunction with this, air from an air tank (not shown) is supplied to the chamber 8 of the brake valve 1.

When air is supplied to the chamber 8 in this way, the piston 6 moves downward in the figure against the return spring 9, and in order to push down the plunger 5, it is sent from an air tank (not shown) to the booster via the brake valve 1. A predetermined air pressure is supplied to the second relay valve.

Note that by appropriately selecting the effective cross-sectional area of the chamber 8 and the set pressure of the return spring 9, any air pressure can be supplied. Therefore,
There is no need to provide an independent pressure reducing valve exclusively for the brake lock as in the prior art, and a part of the service brake air piping can be used as the brake lock air piping, so the configuration can be simplified.

Further, when air higher than the specified pressure is supplied to the relay valve of the booster 2, the pressure switch 39 is open, so the coil 40a of the confirmation relay 40 is not energized, and its contact 40b is closed. . Then, in this state, the confirmation lamp 43 lights up, so the driver can judge from the lighting state of the confirmation lamp 43 whether or not the brake lock device is operating reliably.

To release the brake lock, pull the knob 27 to return the valve body 25 of the manual valve 10 to its closed state. Then, the position switch 33 returns to the open position, and the confirmation lamp 43 goes out. At the same time, the air pressure supplied to the relay valve of the booster 2 also decreases, so the output of the booster 2 decreases and the brake lock state ends.

Furthermore, when the parking brake lever 34 is returned to allow the vehicle to travel, both the parking brake switch 35 and the operating force sensor 38 return to their open states, so that the energization of the solenoid 28 is stopped. Then,
Since the locking pin 29 protrudes and engages again in the groove 30 of the rod 26, the push-in operation of the knob 27 becomes impossible. Therefore, even in the unlikely event that the manual valve 10 opens while the vehicle is running, safety is guaranteed.

On the other hand, if an air leak occurs while the brake is locked and the air pressure supplied to the relay valve of booster 2 becomes lower than a predetermined value, the pressure switch 39
is closed, the warning buzzer 41 is activated, and the confirmation lamp 43 is turned off to notify that an abnormality has occurred. In addition, if fluid leakage occurs, turn on the oil level switch 44 installed in the brake oil reservoir.
Or stroke switch 45 provided on booster 2
When at least one of the brake locks is closed and the warning buzzer 41 is activated, the warning lamp 46 is turned on to notify the driver of this fact, thereby ensuring the safety of the brake lock device.

Furthermore, since the control relay 36 and the confirmation relay 40 are housed in the same relay box 50,
The number of electrical wirings outside the relay box 50 can be reduced, and the number of connection points during assembly can be reduced, thereby greatly improving the workability of mounting onto a vehicle and the workability of maintenance and inspection.

In the embodiment, the preparation completion notification means and the lock confirmation notification means are each constituted by a lamp, but these notification means are not limited to lamps. In the embodiment, when a pressure drop occurs during the brake lock operation, or when the oil level falls below a predetermined value, or when the stroke of the brake booster 2 is smaller than a predetermined value, that is, when a state occurs in which the brake lock cannot be reliably operated even if the pressure of the working fluid of the service brake drops, the warning buzzer 41 is activated to increase the reliability of the lock confirmation notification means, but the drop in pressure of the working fluid can also be constituted by other means. Furthermore, in the embodiment, the present invention is applied to an air-over-hydraulic brake system, but it goes without saying that the present invention can also be applied to ordinary air brake systems that do not include a servo mechanism.

<Effects of the invention> As explained above, in the present invention, parts and piping of the service brake control system are improved so that the brake valve normally operated by the brake pedal functions as a pressure reducing valve when the brake lock is activated. Since the brake lock system is configured to be used for both parts and piping of the brake lock system, the number of parts specific to the brake lock system can be kept to the minimum necessary, and the piping can be simplified, making it possible to add the brake lock system. Increases in weight and cost due to this can be suppressed.
Further, since the system notifies the user that the preparation operation for locking the brake has been completed and that the brake is securely locked, it is possible to prevent erroneous operation and misidentification. Furthermore, if the pressure of the service brake's working fluid drops while the manual valve is operated, a warning buzzer is activated to notify (warn) that the brake lock is not working properly. In addition, malfunctions due to liquid leakage, for example, can be prevented, and together with the simplification of the piping (configuration) described above, the reliability of the brake lock device can be increased. Furthermore, since the control relay and the confirmed relay are housed in the same relay box, the electrical wiring outside the relay box can be simplified and the number of parts used during assembly can be reduced. I can,
This makes it possible to improve work efficiency when mounting (assembling) the brake lock device on an automobile and during maintenance and inspection.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing an embodiment of the present invention.
Fig. 2 is a sectional view showing a specific example of a brake valve, Fig. 3 is a partially cutaway side view showing a specific example of a manual valve, Fig. 4 is a vertical sectional view of Fig. 3, and Fig. 5 1 is a system diagram illustrating a conventional brake lock device. 1... Brake valve, 3... Service brake, 4... Brake pedal, 5... Plunger,
6...Piston, 7...Step, 8...Chamber,
9... Return spring, 10... Manual valve, 28... Solenoid, 29... Lock pin,
33...Position switch, 34...Parking brake lever, 35...Parking brake switch, 3
6... Control relay, 37... Parking brake, 38
...Operating force sensor, 39...Pressure switch, 40
... Confirmation relay, 41 ... Warning buzzer (warning means), 42 ... Operation preparation lamp (ready completion notification means), 43 ... Confirmation lamp (lock confirmation notification means), 44 ... Oil level switch, 45 ...
Stroke switch, 50...Relay box.

Claims (1)

[Scope of utility model registration request] A brake lock device for an automobile, comprising: a brake valve for controlling the braking force of a service brake by changing the stroke of a plunger according to the depression amount of a brake pedal, a piston that contacts the plunger from the return direction of the plunger, a normally closed manual valve that connects a chamber formed by the piston to an air tank, and a return spring that urges the piston to slide in the return direction of the plunger, the brake lock device comprising: a parking brake switch that detects the position of a parking brake lever; and an operating force sensor that detects the operating force of the parking brake.
The parking brake lever is operated to an actuated position via the parking brake switch and the operation force sensor,
a pressure switch for detecting the pressure of the hydraulic fluid supplied to the service brake; a confirmation relay for activating a lock confirmation notification means for notifying the driver that the brakes are securely locked only when the manual valve is operated to the operating position via the position switch and the pressure switch and the pressure of the hydraulic fluid supplied to the service brake is detected to be equal to or higher than a predetermined value; and a warning means for operating when a drop in pressure of the hydraulic fluid occurs while the manual valve is being operated, and the control relay and confirmation relay are housed in the same relay box.