|Title of Invention||
MECHANISM FOR SENSING COLLISION AND ASSISTING REVERSE DRIVING WITH ASSOCIATED ELECTRICAL CIRCUIT FOR SEQUENTIAL OPERATION
|Abstract||A new device along with an electrical circuit for its sequential operation is invented which can be fitted in pairs to the front of automobile, preferably in the bumper location, to detect collision just before actual collision takes place and can generate an electrical signal or give a mechanical output which can be used for automatic braking, cutting off fuel, releasing of clutch etc. The same device can be used to assist driver while driving in reverse direction. When such device(s) are fitted on to rear of automobile, preferable in bumper location, it can assist driver while driving in reverse direction by giving an indication of presence of an obstacle (viz. a wall or another vehicle etc.). The device generates a signal few milliseconds before actual collision and hence time available for activation of various mechanical safety systems is more compared to time available for shock sensors presently being employed. Also driver can be more correctly guided while parking in congested|
|Full Text||Mechanism for sensing collision and assisting reverse driving with associated electrical circuit for sequential operation.
Field of application
This invention relates to the field of automobile safety and utility where collision is sensed electro-mechanically just before the actual dash or collision. A sensor is used to generate electrical signal which can be used for activating various safety measures such as shutting the fuel supply, applying automatic brakes, releasing the clutch, activating devices like air bags etc. Similarly the device when fitted to rear side will assist driver while driving in the reverse direction providing a warning in the event of approach of any obstacle e.g a wall or parked vehicle.
Present day vehicles are equipped with safety devices consisting of sensors, usually shock sensors (viz. MEMS accelerometers), which sense the collision and send signal to open safety air bag. This usually needs a very quick response by air bag deployment system. Since the signal is sent after collision takes place, the stringent requirement to protect the human head and body before he or she strikes the front objects (viz dash board, steering wheel front seat etc.) calls for a very quick response of air bag deployment system which in turn is very costly. The response time available is of the order of few milliseconds. If the collision is detected slightly before hand the response time required may be made double or higher. This will have following advantages.
1. Response time for air bag deployment system is increased, thus a less costly system can be designed.
2. The signal can be used to apply brakes automatically, releasing the clutch, releasing accelerometer pedal etc., there by decreasing the impact force on vehicle and shock load on transmission & engine components. The transmission & engine components can be reused after minor repairs in some occasions.
If presence of any obstacle (viz. a wall or other stationary or moving vehicle) on rear side is detected then it is helpful to the driver as he or she need not look back continuously through window or through rear viewing mirror (which may not give a good estimation of rear objects) or driver need not depend on another person for guidance.
With above requirements in view a collapsible (foldable) electro-mechanical device is designed which is novel, cost effective and useful.
Description of accompanying drawings
1. Fig.la and Fig.lb show typical location of devices at front and rear of an automobile and the configuration of arms in the opened position.
2. Fig.2 shows the direction of opening for a typical device
3. Fig.3 shows top view of the device in closed position.
4. Fig.4 shows front view of the device in closed position.
5. Fig. 5 shows arrangement of stoppers or stop blocks, limit switches, locking arrangement for arm (1) i.e. main arm.
6. Fig.6 shows electrical wiring diagram for sequential operation of motors.
Description of invention
The design is basically a system of arms (links) which open in a definite predetermined manner upon activation. The arms are made to swing out from closed position to the positions shown in Fig.la and Fig.lb in a sequence described later. Any force exerted on any of the arms will cause a mechanical movement and activate a signal which can be used in a multiple ways to bring in various safety measures as described later. The operation of the linkage (a system of arms) is done by using any suitable small DC motors meeting the low speed (typically 4 to 12 RPM) and adequate variable torque requirement.
Brief explanation of the design and operation are given below.
The Design (see Fig.3, Fig.4 & Fig.5)
An arm (1) as shown in Fig.3 & Fig.4 is placed on a support plate (5) and is held in place by a top cover (6) and is free to rotate in one direction w.r.t support plate (5). The arm (1) is held in place by a spring (17) which is attached to support plate (5) through a lug (18) as shovra in Fig.3. The arm (1) is prevented to rotate in the direction opposite to opening direction of arm (1) by a stopper pin (20) which is attached to (5). The top cover (6) is fixed to (5) by a nut (7) so that the arm (1) swings in the gap between (6) and (5). To avoid problem of rattling of arm (1) in the gap between (5) and (6) a roller (32) made of suitable rubber is kept pressed on to (6) as shown in Fig.4. The roller (32) is held by holder (33) which is fixed to (1).
Support plate (5) is attached to the shaft of a suitable motor (4). Motor (4) is fixed to housing (8) as shovra in fig.4 by using metal/hard spacers (34) which are not flexible. A roller (10) is pivoted on a mounting block (11) which in turn is attached to support
plate (5) through a rubber pad (12). The roller (10) is kept lightly pressed on to a semicircular collar (9) fitted to the housing (8). The roller (10) is a lined with rubber to reduce vibration problems.
The movement of motor is restricted to a certain angle (typically 120 to 140 degrees) by providing stoppers or stopper blocks (15) [see Fig.5] at the ends of semicircular collar (9), so that the motor (4) is tripped when the roller (10) comes to the stopper and presses a limit switch (35) housed in the stopper or stopper block. Once the roller reaches any end, the roller (10) is prevented from freely moving back by a leaf spring (14) attached to collar (9) in a suitable way such as shown in Fig.5. Only when motor is rotated in opposite direction the roller rides over leaf spring (14) and travels to the other end where similar stopper with limit switch and leaf spring are provided. The surface of leaf spring on which roller rides may be made rough enough by passing a sticker having rough corrugated face. If motor is having self locking (as in stepper motor) then the arrangement of (14), (15) and (35) is not required. Alternately, a electrically engerised clutch may be used to hold the shaft of motor at the ends of its travel)
Arm (1) is made of light material viz. Aluminum or plastic suitably provided with stiffeners to have light weight and good rigidity.
A small motor (21) is fitted at the end of arm (1), the shaft of which carries an arm (2) which initially is parallel with arm (1). This motor (21) is made to rotate by approximately 90 degrees slowly so that the arm (2) can be brought up perpendicular to arm (1). A pulley (22) is fitted to the shaft of motor (21). Another pulley (23) is fitted on to arm (1) at a middle location. A suitable belt (24) connects these two pulleys. Integral with pulley (23) a geared wheel (25) is provided which is engaged with another geared wheel (26) whose axis is perpendicular to axis is of (25). (25) and (26) make a bevel gear set. The geared wheel (26) is having an axially extended central hub. On the hub of (26) a carrier plate (5a) having a central hub, an arm (3) and a cover plate (6a) are fixed in the similar way as that of arm (1). A stopper pin (27) is attached to (6a) to prevent rotation of arm (3) in the direction of opening of arm (1). A spring (29) attached at one end to a block (30) keeps the arm (3) pressed against pin (27), similar to the way in which spring (17) keeps arm (1) pressed against pin (20) in normal situation i.e. until a force is exerted on arm (1).
The gear ratio and pulley diameter ratios are maintained such that when arm (2) rotates by about 90 degrees, the gear (26) rotates by about same angle as that of the rotation of arm (1) i.e. 120 to 140 degrees. The arm (3) is provided with an extension (28), which comes in close vicinity of arm (1) when rotated by an angle 120-140 degrees i.e. when it reaches its extreme position. When a force is exerted on (3) it pushes extended portion of arm (1) against force of spring (29).
The motor (21) is made to rotate by approximately 90 degrees and the motor is stopped and locked at the end of its 90 degree travel by arrangements similar to (15), (35) and (14) fitted between two concentric collars provided on a semicircular plate which in turn is fitted on a bracket; the bracket is attached to the arm (1). A roller (10a) is attached to shaft of motor (21) and the roller (10a) rides on a collar in between above mentioned
concentric collars, ine arm (ij provided with a cover (31) Freterably made ot plastic or fiber, as shown in Fig.3 to hide entire mechanism inside when the mechanism is in closed position . Similarly, another cover (36) is provided on other side such that it does not obstruct the movement of arm (3). The whole mechanism can be housed inside bumper of vehicles and the housing (8) is suitably placed on soft mountings (37) to take care of vibration transmission from vehicle to the mechanism.
Operation (see Fig.2 & Fig.6)
For the operation of motors in a definite way a circuit is arranged as shown in Fig.6. The sequence of operation is as follows.
1. Upon putting the push-pull switch to "open" position the motor (4) operates and arm (1) swings from normal position to final position (by approximately!20 to 140 degrees).
2. Once the arm (1) reaches its end of desired travel, a normally closed (NC) limit switch (LSo) becomes open and cuts off the supply to motor (4). And another normally open (NO) limit switch (LS) closes the supply circuit to the motor (21).
3. Then the motor (21) takes the arm (2) to its extreme position (i.e. approx 90 degrees from normal close position). A NC limit switch (LSi) is operated by roller (10a) and the supply to (21) is cut off.
4. While arm (2) rotates it rotates arm (3) through gearing arrangement as described before to the extreme position of arm (3). The final configuration of arms is as shown in Fig.2 / Fig. 1 a / Fig. 1 b.
5. Whenever an object such as another vehicle pushes any these arms, the final effect is to push the arm (1) further in the direction in which it is opened i.e. arm (1) will swing against spring load from (17) to a higher angle i.e. more than 120 to 140 degrees of its normal open position. This extra movement activates a limit switch (19). This closes an electrical circuit giving an output signal. This signal can be used for initiating a variety of actives such as:-
-Danger signal to the other vehicle(s).
-Activating air bag deployment system.
-Activating a mechanism to cut off fuel supply.
-Activating a mechanism to apply sudden brakes etc. -Releasing clutch to protect engine from torsional shock.
6. For normal closure of mechanism (in the likely event of no collision) first, the motor (21) has to rotate in opposite direction by similar angle i.e. approximately 90 degrees. For this the switch (push-pull type) shall be put in "close" position.
7. When switch is brought to "close" position a switch (S) is closed and supply is made available with reverse polarity to motor (21) through a NC limit switch (LSB).
8. Just before the arm (2) and (3) reach normal closed position the NO limit switch (LS2) becomes closed and supply with reverse polarity is made available to motor (4). The moment arm (1) moves back from its extreme position the limit switch (LS) becomes open and supply to motor (21) is cut off as the limit switch (LS3) also becomes open at the end of travel of arm (2). It may be noted that the limit switches (LS3) and (LS2) are so arranged at the starting position of arm (2) that firstly (LS2) is operated and after a short gap i.e. after motor (4) is energised with reverse polarity and (LS) becomes open, (LS3) is activated to make it open and cut off the supply to motor (4). For this limit switch (LS2) shall be backed by a small spring (which shall be slightly harder than the spring inside limit switch LS2) in its housing so that roller (10a) will first activate (LS2) and push this whole switch further into its housing i.e. stopper block for pressing the limit switch (LS3) at the end of travel of roller (10a) which is attached to arm (2).
9. After the arm (1) swings back to its normal closed position and at the end it opens a NC limit switch (LSc), thus cutting off the supply to motor (4).
10. Oppositely moving or stationery vehicle will touch either arm (2) or (3) or end of arm (1) and the force on either of these arms will cause the arm (1) to swing further away activating the limit switch (19). This limit switch closes a circuit and sends an electrical signal. The extra mechanical movement of arm (1) against spring force from (17) may also be used to mechanically activate any link of another mechanism. The output motion i.e. extra motion can be transferred mechanically to other mechanisms used to activate brake or releasing the accelerator pedal etc.
11. The mechanism, when fitted to the rear of a vehicle (preferably in the bumper location i.e. in a slot in the bumper), is useful for the driver as he can drive in backward direction (e.g. while parking a vehicle) without seeing continuously backside through window or through rear mirror (which does not give a good estimate). Whenever an obstacle is touched by the mechanism a signal can be given to driver so that he can apply brakes. Alternately, auto braking can be employed by suitable means.
The above explained device is to be used in pairs and shall be placed symmetrically about longitudinal axis of the automobile, either at front or rear or on both sides, in the pockets made in bumpers. The design features of the devices in a pair are mirror images of each other.
Claims of the Invention
1. A device consisting of three arms, all of which remain close together having their
axes parallel to each other and in horizontal position when in closed position and
which when opened spread out in such manner that
(i) the amount of rotation for the main arm being approximately 120 to 140 degrees in a direction away from longitudinal centre line of vehicle on to which the system is fitted; the axis of rotation of the said main arm is vertical.
(ii) the amount of rotation of the second arm being approximately 90 degrees in the upward direction and assumes a near vertical position; the axis of rotation of the said second arm is horizontal.
(iii) the amount of rotation of the third arm being approximately same as that of said main arm but the spread of this third arm being in opposite direction to that of said main arm; said third arm occupies a horizontal position perpendicular to direction of movement of vehicle on to which the system fitted either on front or rear side; the axis of rotation of the said third arm is vertical.
2. The device claimed in claim 1 wherein the rotations of said main arm being done by a suitable drive such as a low rpm DC motor mounted on a housing such that its shaft is in vertical direction; the said housing is mounted inside a pocket in the bumper on the vehicle or any other suitable location either at front or rear side or in both sides of the vehicle.
3. The device claimed in claim 2 wherein
(i) a support plate being fixed to the shaft of said motor rigidly and a top cover attached to an integral central hub on the said support plate; the main arm is placed in between the said support plate and top cover plate such that the said main arm can rotate w.r.t support plate in which the relative rotation being prevented in the opposite direction of the opening of said main arm by a pin fixed on to said support plate and the main arm is kept in contact with said pin by a spring fixed to support plate, hence
requiring a force on the said main arm to make it rotate what support plate in the direction of opening.
(ii) the rotation of the said main arm is limited by putting stop blocks at the ends of its desired travel which stops a roller attached to the said support plate; the said roller runs on a circumferential collar fixed to the said housing and said stop blocks are placed at the ends of collar ; and to retain the said roller in place and disallow any free movement of said main arm, a mechanical leaf spring lock is arranged at each end; the said roller rides over the leaf spring and gets trapped between leaf spring and the stop block at each end.
4. The device claimed in claim 3
(i) at the end of said main arm a second motor, similar to said motor in claim 2, is fitted such that its shaft is in horizontal position and carries a second arm on to which a roller is attached, the said roller on second arm runs over an arc shaped collar fitted on to a plate which in turn is attached to said main arm through a bracket.
(ii) two stop blocks along with arrangement for locking as described in claim 3(ii) are placed at the ends of travel of the second arm to stop and lock the roller attached to second arm; this arrangement being similar to the arrangement to limit and lock the movement of said main arm.
(iii) a pulley is attached to the shaft of said second motor; the said pulley runs a second pulley placed down the length of said main arm by a suitable non-slipping belt.
(iv) a gear wheel is attached the said second pulley whose axis is horizontal; this gear turns another gear wheel whose axis is vertical; above said two gears make a bevel gear pair.
5. The device claimed m claim 4 wherein
(i) a support plate with a central hub with a cover plate on the hub is fixed to the said gear wheel with vertical axis and a third arm is placed in between the above said support plate and cover plate in the similar manner as that of the placement of first arm as explained in claim 3.
(ii) the said third arm is not allowed to rotate what. its support plate in the opposite direction of its opening by a pin fixed to support plate of said third arm and third arm is kept pressed against the above said pin by a spring force where in the spring is fixed on to above said support plate in a manner similar to the way in which main arm is constrained as explained in claim 3.
(iii) the said third arm is provided with a projection in such a manner that when it is in opened position the projection lies very close to the said main arm so that when an object pushes the said third arm it moves further in its direction of opening against the spring force and pushes the said main arm further in the direction of opening of main arm.
6. The device claimed in claim 1 to 5 wherein at the end of travel of the said main arm and the second arm i.e. within pockets made on stop blocks following limit switches are placed.
- One normally closed (NC) limit switch in the stop block corresponding to closed position of main arm.
- One normally closed (NC) and another normally open (NO) limit switch in the stop block at the end of travel of the said main arm i.e. at the position corresponding to open position of main arm.
One normally closed (NC) and another normally open (NO) limit switch in the stop block corresponding to closed position of the said second arm.
One normally closed (NC) limit switch in the stop block at the end of travel of the said second arm i.e. at the position corresponding to open position of the second arm.
7. The wiring of two said motors using a mechanical two position switch, the limit switches described in claim 6 and a suitable battery (DC supply source) is as shown and explained in Fig.6.
8. The method of putting pairs of such devices as claimed in claim 1 to 6 symmetrically about longitudinal axis of the automobile, either at front or rear or on both sides in the pockets made in bumpers where in the design features of the devices in a pair are mirror images of each other.
9. The method of detection of collision where in a push given to any of the three above said arms in opened position by an object or vehicle ahead or behind causes the said main arm to swing further in the opening direction of the main arm against the force of said spring mentioned in claim 3, pressing a limit switch attached to support plate of the main arm and closing an electrical circuit thereby generating an electrical signal; the said electrical signal is used to activate many safety devices such as air bag deployment, auto braking, cutting off the fuel supply to engine, disengaging of clutch etc. in case of head on collision OR an alarm to driver when the vehicle is driven in the reverse direction etc.
10. A system of devices for detection of a head on collision to an automobile or an obstacle in the rear of the automobile, substantially as herein described and illustrated in the accompanying drawings.
Summary of invention
A new device is designed which when fitted in a pair to the front of automobile, preferable in bumper location, and opened can detect any collision little before the actual collision takes place and can activate various safety systems viz. deployment of air bags ,applying of brakes , cutting off fuel supply or releasing of clutch etc. When fitted in the rear of automobile in a pair, preferably in bumper location, it can assist driver while driving in reverse direction by giving an indication of presence of an obstacle (viz. a wall or another vehicle etc.). An electrical circuit is also designed to operate the two motors of each device in a sequential manner employing a two position push-pull type of mechanical switch. The essential advantage of the new system over the present shock sensors for deployment of air bags is that the warning comes few milliseconds before the collision and hence offers two advantages i.e. (i) the driver and passengers get protection before they experience the shock and (ii) time available for response of the air bag deployment is more, allowing a cheaper air bag deployment system can be designed.
|Indian Patent Application Number||2404/CHE/2007|
|PG Journal Number||30/2012|
|Date of Filing||24-Oct-2007|
|Name of Patentee||CH.RABI KUMAR|
|Applicant Address||43, Type 3, CPRI Colony, New Bel Road, Bangalore - 560 012.|
|PCT International Classification Number||G01P 15/00|
|PCT International Application Number||N/A|
|PCT International Filing date|