FR2769939A1 - Motor vehicle door stop - Google Patents

Abstract

The door stop comprises a sealed rigid casing (1) containing a fluid. A piston (3) pivoted in the casing by a spindle (2) subdivides the casing into two variable volume chambers (51,52). The piston has two directional valves (41,42) with opposite release thresholds. Each valve controls a narrow passage connecting the two chambers when the pressure in one of them exceeds that in the other by a difference greater than the threshold of the corresponding valve in the direction of fluid flow from the high pressure chamber to the other.

Description

 The present invention relates to a door stop, in particular for a motor vehicle, intended to connect the two parts of the joint (door / bodywork) to one another in order to retain them in any position.

 There are multiple forms of door stops for motor vehicles. These door stops are intended to keep the door in the open position. To close the door it is necessary to pull it by exerting a force greater than that which would normally be necessary in the absence of a door stop, to overcome the holding torque of the door stop. This torque is generally generated by a boss or a cavity in the tongue of the door stop and which forces the rollers rolling on this tongue to move apart against the action of an elastic element such as a spring or by the deformation of an elastic part.

 These door stops all have one or possibly more discrete restraint positions.

 The present invention aims to remedy these drawbacks and proposes to create a door stop for retaining a door in any intermediate position between the closed position and the largest open position.

To this end, the invention relates to a door stop, in particular for a motor vehicle, characterized in that it comprises - a rigid casing closed in leaktight manner containing a
fluid, this housing being connected to a part of
the joint, - a piston mounted pivoting in the housing by a solid axis
of the piston and at least one end of which protrudes from the
housing to be connected to the other part of
the joint, - this piston dividing the housing into two volume chambers
variable, complementary, - the piston being provided with two directional threshold valves
opposite trigger, each commanding a passage
strangled connecting the two chambers when the pressure in
one of the rooms exceeds that of the other by a different
rence greater than the valve threshold corresponding to the direction
fluid passage from the high pressure chamber to the other.

 The door stop according to the invention retains the door in any position in which the door is left, that is to say in any relative pivoting position between the piston and the housing since when the door is stopped, the piston no longer exerts a compression force on the fluid located in the upstream chamber, so that the pressures of the fluid in the upstream chamber and in the downstream chamber are close. The fluid in the two chambers thus blocks the piston since it cannot pass through any of the two opposite valves. After stopping, the situation changes since only a force exerted on the door and generating a pressure greater than that of the threshold of the valve corresponding to this movement can move the door.

 The thresholds are preferably identical but they can be different. In no case is the identity of the thresholds essential and does not constitute an aim of adjustment.

 To move the door from the position in which it is stopped by the door stop, it must be pulled or pushed in the desired direction to generate in the upstream chamber a pressure such that its difference with the pressure of the downstream chamber exceeds the opening threshold of the valve provided to open and allow communication between the two chambers.

 At this time, as this pressure difference acts in the opposite operating direction on the other valve (the latter being disposed in opposition to the previous valve), it cannot open.

 Conversely, when exercising on the door in the stopped position, a torque opposite to the previous torque, and when the pressure difference in this direction exceeds that of the threshold of the second valve, the latter opens and releases the movement.

 As soon as the external torque exerted on the door disappears, the piston comes to a standstill and, by the very fact of its immobilization, the pressures in the two chambers are balanced, regardless of the relative position of the piston. The piston is then locked in this position and it locks the door in the corresponding position.

 In general, the door stop is associated with an articulation in two parts constituted for example by the bodywork and a vehicle door. Other applications are possible.

 This door stop is preferably mounted so that the relative axis of rotation between the piston and the door stop coincides with the axis of rotation of the door. However, link and motion transmission mechanisms can be envisaged if the door stop cannot be mounted coaxially with the pivot axis of the door as mentioned above.

 Generally and by convention, the terms upstream and downstream will designate the chamber which is located upstream of the piston according to its direction of rotation and that which is downstream.

 Therefore, the upstream and downstream qualifiers only depend on the direction in which the piston pivots or must pivot.

 The constricted passage which is released by one of the valves during the displacement of the piston generates a pressure drop making it possible to maintain a pressure difference on either side of the shutter member of the corresponding valve.

In a particularly advantageous manner, the directional valve with triggering threshold comprises - a stepped passage having as input a passage of small dry
tion opening into the upstream chamber and a passage
large diameter opening into the downstream chamber, - these two passages of different diameters forming between them
a shoulder into which the upstream passage opens into y
producing the valve seat with which a member cooperates
shutter loaded by a calibrated spring, - the throttled passage connecting the inside of the valve downstream
from the seat to the downstream chamber.

 This valve is of a very simple realization.

This embodiment also relates to the piston which is for example a solid part, in which there are simply produced two stepped passages, directed in opposite directions, and a constricted passage for each valve.

 In this valve, the shutter member is preferably a ball.

 According to another particularly advantageous characteristic, the large-diameter passage receives a sheath in which the ball moves making a sealed separation between the fluid of the upstream chamber and that of the downstream chamber on the two sides of the ball.

 This sheath prevents any leakage of liquid directly through the separation formed by the ball released from its seat, to force all the liquid to pass through the constricted passage.

 According to another advantageous characteristic, the spring charging the shutter member of the valve is a Belleville spring.

 According to another advantageous characteristic, the spring loading the shutter member of the valve rests, on the one hand, on the shutter member, and, on the other hand, on a drilled screw, housed in an adjustable manner in the large diameter passage, tapped over at least part of its length.

 This mounting of the spring in its housing is very simple and the drilled screw makes it possible to adjust the calibration of the spring.

 As already indicated, it is not essential for the operation of the door stop that the springs of the two valves are tared in exactly the same way.

 The spring setting regulates the valve opening threshold, that is to say the pressure difference that must be generated by the torque initially applied to the door. This torque decreases as soon as the threshold is exceeded and the valve is open.

 Indeed, the shutter member such as the ball is pushed by a determined force, exerted by the calibrated spring. To generate this force when the valve is closed, it is necessary to exert a significant pressure on the small surface of the closure member accessible at the level of the valve seat.

 But as soon as the shutter member is lifted from its seat, the entire corresponding face can be subjected to pressure. It therefore requires a much lower pressure to keep the shutter member in the open position.

 If the passage was not throttled, the pressures would balance in an almost immediate manner in the two chambers and the valve would come back to apply almost immediately against its seat which it would block. It would again be necessary to exert a torque generating a pressure difference greater than the threshold to raise the valve again from its seat. The balance would immediately start again and so on. There would be a jerky opening movement of the door and it would be necessary to constantly exert the significant torque necessary for the initial pivoting of the door from its stopped position.

 According to another advantageous characteristic of the invention, one of the chambers has an adjustable stopper, forming an end of travel stop for the piston and making it possible to adjust the pressure in the two chambers. This end of travel stop is preferably associated with the end of opening stroke of a car door.

 According to another characteristic, the housing is in the form of a sector of a circle and comprises two housings forming a bearing for the axis of the piston, this housing being produced in two parts, a lower part forming a tank and an upper part forming a cover.

 According to another advantageous characteristic, the housing includes a recess on part of the piston path to allow the two chambers to communicate freely and to neutralize the door stop function on this path.

The present invention will be described below in more detail with the aid of the accompanying drawings in which
FIG. 1 is an axial section view of the valve according to plane II of FIG. 2,
FIG. 2 is a top view of the valve of FIG. 1 cut along the plane II-II,
FIG. 3 is an exploded perspective view of the piston,
FIG. 4 is a sectional view along the section plane IV-IV of FIG. 2,
According to Figures 1 and 2, the invention relates to a door stop intended in particular to equip the doors of motor vehicles generally corresponding to two parts hinged to each other, one of the parts being the door, l other body. These two parties are not represented.

 These two parts can be connected either to one or the other of the two parts of the door stop, namely the housing or the piston.

 The purpose of this door stop is to hold the door in any open position relative to the body.

 This door stop consists of a housing 1 in two parts 11, 12, one constituting a tank, the other its cover. These two parts are tightly assembled.

The box has, as shown in FIG. 2, a shape of a circle sector or more exactly of a circle sector envelope, the center of which is formed by the pivot axis 2. This box, rigid, tightly closed, contains a fluid such as a hydraulic fluid, a gas or a semi-solid fluid (pasty fluid).

 The cavity of this housing 1 houses a pivoting piston 3 provided with an axis coaxial with the geometric axis 2 and one end or axis element 31 of which is housed in a closed part 13 of the housing 1 which constitutes a bearing; the other end or axis element 32 passes through a sleeve 14 of the cover 12 of the housing 1 in a sealed manner.

 The housing 1 is connected to one of the parts of the articulation (body or door) and the end 32 of the axis of the piston is connected to the other part of the articulation (door or body).

 The piston 3 can perform a pivoting movement in the housing 1 around the geometric axis 2. The shape of the housing cavity 1 allows this pivoting movement whose angle a (relative to the axis 2) depends on the degree of openness that the joint must offer (with or without reduction in movement).

 The piston 3 consists of a bar 33 of section substantially equal to the section of the cavity of the housing 1.

This bar 33 ends with an end 34 carrying the two axis elements 31, 32 and by an end 35 provided with two directional valves 41, 42. The piston 3 has at its periphery a seal 36. This seal 36 also surrounds the axis elements 31, 32 to ensure a sealed separation between the two chambers 51, 52 delimited by the piston 3 in the cavity of the housing 1.

 It should be noted that the sealing of the axis element 32 leaving the housing 1 is possibly ensured by a complementary seal 320.

 The housing 1 is also provided with an end of travel stop 6 housed in a sleeve 15 provided on the side of the housing 1 and opening into the chamber 52.

 This end-of-travel stop consists of a plug 61 housed in a sealed manner in the sleeve 15, pressing by means of an elastic element 62 against an adjustment screw 63 screwed into the thread of the sleeve 15. The more or less significant screwing of the stop in the sleeve 15 makes it possible to adjust the pressure prevailing in the cavity of the housing 1.

 The piston 18 protrudes slightly from the interior wall of the housing 1 to serve as an end-of-travel stop for the piston 3.

 According to FIG. 2, the opening movement of the door corresponds to the movement of the piston 3 in the direction of the arrow A. When the door is closed, the piston 3 is applied against the side 17 of the housing 1 while at the end opening stroke the piston is applied against the stop 6.

 Generally, a door stop does not have to intervene in the operation of the door on opening and closing. It must be disabled for these two phases of the door movement. The opening must be possible without requiring a particular effort. The closing of the door must be free to allow the door to be slammed, which is the guarantee of the correct engagement of the lock.

 In addition, the opening of a vehicle door must be able to be done without any particular effort up to an opening degree or angle allowing the passenger to exit the vehicle. The door stop function must only intervene beyond this movement, both in the opening and closing directions.

 For this reason, the housing 1 has a recess or channel 16 or more generally a means of communication allowing free communication between the chambers 51 and 52 so as to neutralize the door stop function. At the recess 16, the seal 36 of the piston 3 is no longer in contact with the wall of the housing so that the hydraulic fluid can pass freely between the chambers, on either side of the piston 3. The length of this offset (arc or angle) 16 corresponds to the free opening angle of the door without intervention of the door stop function.

 The shape of the piston 3 appears particularly well in FIG. 3. This FIG. 3 also shows, in exploded view, the structure of the valve 41. The more particular shape of the valve appears in the sectional view of FIG. 4.

 The piston 3 subdivides the cavity of the housing 1 into two chambers 51, 52. If it is assumed that the piston 3 is rotated (or pivoted) around the axis 2, in the direction of the arrow A, we will call upstream chamber the chamber 52 which is located in front of the piston 3; the downstream chamber will be the chamber 51 located at the rear of the piston 3.

 The qualifier assigned to the chambers 51, 52 is reversed when the piston 3 pivots in the direction opposite to that given by the arrow A. The chamber 51 then becomes the upstream chamber and the chamber 52 the downstream chamber.

 The valves 41, 42 of the piston act in opposite directions. I1 are directional valves opening with a triggering threshold dependent on the pressure difference prevailing on either side of the valve, that is to say on the pressure difference of the fluid in the two chambers 51 , 52.

Each valve 41, 42 controls a throttled passage 410, 420 connecting the inlet of the valve downstream of its shutter member to the other chamber than that with which the inlet of the valve communicates.

 The description of this part of the piston and of the valves will be made in more detail afterwards with the aid of FIGS. 2, 3, 4.

 It should be noted that the structure of the two valves 41, 42 is also identical and the description will be limited to that of the valve 41 especially with the aid of FIGS. 3 and 4.

 The valve 41 is intended to release the passage 410 (FIGS. 3 and 4) connecting the chamber 52 (in which the highest pressure presumably prevails) to the chamber 51 when the difference between the two pressures exceeds the triggering threshold of the valve .

 The valve 41 comprises a stepped passage formed in the body 35 and consisting at the inlet, on the side of the chamber 52, of a passage of small section 411 and on the other side, opening into the chamber 51, of a passage large section 412. These passages form between them a shoulder 413 in which the small section passage 411 defines a valve seat 414. The valve is closed by a shutter member 415 in the form of a ball. This shutter member is housed inside the passage of large section 412 in a sleeve 416 with which it is in sealed contact. This sheath is itself sealed in the passage 412.

 A spring 417 is pressed against the closure member 415. By its other end, the spring 417 is supported on a drilled screw 418 provided with a bore 419 which passes through it completely. This screw 418 is screwed into the tapped part of the passage of large section 412 to compress the spring 417 in a tared manner fixing the triggering threshold of the valve.

 The sheath 416 clears the constricted passage 410 as shown.

 The operation of this valve 41 is initially as follows, by assumption, the pressure of the fluid in the two chambers 51, 52 is identical. The piston is in equilibrium and the valve is closed. Its closure member 415 is applied by the spring 417 against its seat 413.

 When a force is exerted on one of the parts of the door joint) this force or this torque results in compression of the fluid in one of the chambers 51, 52.

 For the description of this operation, by way of example, it is assumed that this effort increases the pressure of the fluid in the chamber 52 and decreases that of the fluid in the chamber 51.

 The difference between the two pressures is exerted through the passage of small section 411 on the part of the closure member 415 exposed in the passage 411. When the product of this pressure (difference in pressure) and the exposed surface is equal to or slightly greater than the closing force exerted by the spring 417 on the closure member 415, the latter is lifted from its seat 413. As soon as it opens, the difference in pressure is no longer exerted only on the small surface described above of the shutter member 415 but on the entire side thereof exposed to this fluid from the chamber 52. In fact, the entire surface of the shutter member 415 located on the side of the chamber 52 is subjected to the pressure prevailing in the chamber 52 and the entire surface of the shutter member 415 facing the chamber 51 is subjected to the pressure of the fluid prevailing in this chamber 51 via the passage 419 passing through nut 418. As long as a force is exerted on the piston to move it in the same direction, there remains a difference in pressure of the fluids of the chambers 52 and 51.

To keep the shutter member 415 in the open position, a much smaller pressure difference is sufficient than that necessary for the initial release of the valve, since this pressure difference no longer applies to the small area of the shutter member but practically over the entire section of the passage 412.

 In other words, the pressure difference necessary for the continuation of the movement is a first approximation in the inverse ratio of the sections of the passages 411, 412.

 This pressure difference is kept thanks to the throttled passage 410 which prevents its almost immediate collapse by the almost immediate exchange of the fluid between the chambers 52 and 51. This keeps the valve open as long as a relatively small force is exerted on the door. This extremely low effort translates the will of the user who manipulates the door, to continue to move it in the chosen direction.

 In the description of the operation of the valve made with the aid of FIG. 4, the chamber 52 constitutes the upstream chamber (in which the highest pressure prevails) and the downstream chamber 51 (in which regulates the lowest pressure).

 As the valve 41 is unidirectional, that is to say that it can release the communication only from the chamber 52 towards the chamber 51, the upstream and downstream concepts, which are relative in the case of the chambers, are absolute in the case of valve 41. The same remark applies to valve 42.

 The operation of the valve 41 having been described, it is easy to imagine the reverse operation of the valve 42 which is also a valve with a triggering threshold.

 While the valve 41 is associated with the direction of rotation indicated by arrow A, the operation of the valve 42 is associated with the opposite direction of rotation.

Claims (8)

CLAIMS 10) Door stop, in particular for a motor vehicle, intended to connect the two parts of the joint (door / bodywork) to one another to retain them in any position, characterized in that it comprises - a rigid casing (1), sealed, containing a fluid, this casing being connected to a part of the joint, - a piston (3) pivotally mounted (2) in the casing (1) by an axis (31, 32) integral with the piston (3) and of which at least one end (32) protrudes from the housing (1) to be connected to the other part of the articulation, - this piston (3) dividing the housing (1) into two chambers (51, 52) of variable volume, complementary, - the piston (3) being provided with two directional valves (41,  42) at the threshold, opposite, each commanding a  choked passage (410, 420) connecting the two chambers (51,  52) when the pressure in one of the chambers exceeds  that of the other by a difference greater than the threshold of  valve corresponding to the direction of passage of the fluid from the  high pressure chamber towards each other. 20) Door stop according to claim 1, characterized in that the directional valve with triggering threshold (41) comprises - a stepped passage (411, 412) having as input a passage of  small section (411) opening into the upstream chamber (52)  and a large diameter passage (412) opening into the  downstream chamber (51), - these two passages of different diameters forming between them  a shoulder (413) into which the upstream passage opens  (411) by producing therein the valve seat (414) with which  a sealing member (415) cooperates with a spring  calibrated (417), - the throttled passage (410) connecting the interior of the valve  (41), downstream of the seat (414) to the downstream chamber (51).  3) Door stop according to claim 2, characterized in that the shutter member is a ball (415). 40) door stop according to claims 1 and 2, characterized in that the large diameter passage (412) receives a sheath (416) in which the ball (415) moves which achieves a sealed separation between the fluid of the chamber upstream (52) and that of the downstream chamber (51) on both sides of the ball (415). 50) Door stop according to claim 2, characterized in that the spring (417) loading the shutter member (415) of the valve is a Belleville spring. 60) Door stopper according to claim 2, characterized in that the spring (417) loading the shutter member (415) of the valve rests, on the one hand, on the shutter member, and, on the other hand, on a drilled screw (418), housed in an adjustable manner in the large diameter passage (412), tapped over at least part of its length. 70) Door stopper according to claim 1, characterized in that one (52) of the chambers (51, 52) comprises a plug (6), adjustable, forming a limit stop for the piston (3) and allowing to regulate the pressure in the two chambers (51, 52). 80) Door stopper according to claim 1, characterized in that the housing (1) is in the form of a sector of a circle and comprises two housings (13, 14) forming a bearing for the axis (31, 32) of the piston (3 ), this housing (1) being produced in two parts, a lower part (11) forming a tank and an upper part (12) forming a cover. 90) Door stopper according to claim 1, characterized in that the housing comprises a recess (16) on a part of the piston path (3) to allow the two chambers (51, 52) to communicate freely and to neutralize the path door stop function.