JPH0541952Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention is applicable to an input member of a hydraulic master cylinder, for example, a master cylinder of a clutch hydraulic control system of a vehicle, a master cylinder of a hydraulic brake system of a vehicle, etc. It pertains to an electric switch operated by.

BACKGROUND OF THE INVENTION Electric switches are often used in conjunction with the master cylinder of a vehicle's hydraulic brake system. For example, when the driver applies the brakes, the hydraulic brake system conducts an electric circuit that turns on a stop signal light of the vehicle, and/or a cruise control system.
system) is used to switch from active mode to non-active mode. Such electrical switches are generally of the pressure operated type. These electrical switches are actuated by moving the brake pedal to move the master cylinder piston a commensurate distance, thereby increasing the pressure of the hydraulic fluid in the master cylinder in front of the piston.

PROBLEMS SOLVED BY THE INVENTION Pressure operated switches are expensive to manufacture, and they must be mounted at least partially inside the master cylinder.
These switches are actuated by a small increase in fluid pressure and can signal a stop with even the slightest application of the brakes, and can shut off the cruise control system with even the slightest foot pressure on the brake pedal. As a result, these switches are often unreliable.

The function of pressure operated switches can often be inconsistent under special conditions where hydraulic fluid back pressure is applied to the master cylinder. This backpressure is caused, for example, by thermal expansion of the brake lining and thermal expansion of the hydraulic fluid. This unstable function of the pressure-operated switch makes the ON/OFF operation of the vehicle's stop signal light unstable, causing a driving nuisance, especially for the driver of the vehicle directly behind.

Hydraulic control devices for mechanical vehicle clutches are intended to operate the declutching mechanism and conventional active shift transmission or gearbox of a vehicle equipped with a mechanical clutch.
It is rapidly becoming standardized in the industry. Examples of such hydraulic systems for mechanical clutches are U.S. Pat. No. 4,407,125 and related applications.
Serial No. 371958, No. 376248, No. 477161, No.
No. 477162, No. 477159, No. 477160, No. 537869
No. 555667, No. 555666, and No. 555668. All these applications are assigned to the same assignee as the present application. BACKGROUND OF THE INVENTION In the automotive industry, it is common practice to coordinate the operation of an engine starting motor with other control devices in a vehicle. In this way, the starting motor is activated until this transmission is placed in neutral or parked in the case of vehicles with automatic transmissions or with foot-actuated clutches and manually operated gearshift transmissions. In a vehicle, the transmission is deactivated until the transmission is placed in neutral and/or the clutch pedal is fully depressed to fully release the clutch. Additionally, in vehicles equipped with a cruise control system and a mechanical clutch, the cruise control system is often deactivated, for example, when performing a shift operation necessary to release the clutch. However, even before the clutch is fully released, the cruise control system is shut off, allowing the driver to stop the cruise control system by slightly pressing the clutch pedal with his or her foot, and "footing" the clutch, i.e., driving the vehicle. Although it is desirable to prevent a person's foot from being left on the clutch pedal, it is difficult to ensure that such operation occurs due to the instability described above with a pressure-operated switch. I can't.

(Means for Solving the Problems) The present invention is an electric switch provided in a hydraulic master cylinder having a linearly movable input member, wherein the electric switch is operable from an original position. The electrical switch is adapted to be actuated by the input member during movement to the position, and the electrical switch includes a pair of movable elements and a pair of fixed elements, the movable elements being non-contactable with respect to the fixed elements. The movable element is adapted to be moved by the input member from a first position in operative relationship to a second position cooperating with the fixed element, the first position of the movable element being at the original position of the input member. The second position of the movable element corresponds to the starting point of the actuating position, and the movable element moves from the starting point of the actuating position to the final point of the actuating position. cooperating with said stationary element, and further adapted, in use, to control an electrical circuit comprising said stationary element or said movable element;
This control is performed by moving the movable element to the second position and cooperating with the fixed element, the fixed element being controlled by a housing mounted on the cylinder or by the input member. a plunger extending into a housing carried by the cylinder and engaging a stationary portion of the master cylinder, the movable element extending into a housing mounted on the cylinder; or a housing supported by the input member.

(Example) Hereinafter, an example of the present invention will be described according to the drawings. All like reference numbers in the drawings indicate the same or equivalent parts.

Reference is made to the drawings, in particular FIGS. 1 and 2.

The invention is in the form of an electric switch 10. This electric switch is connected to hydraulic master cylinder 1.
It is housed within an insulated plastic housing 12 attached to the end of the 4. Hydraulic master cylinder 14 may be, for example, the master cylinder of a vehicle's clutch hydraulic control system (FIG. 1), as described in detail in the aforementioned U.S. patents and related applications, or the vehicle's hydraulic brake system. Figure 1a is the master cylinder of the system.

As is well known in the art, a linearly movable input member in the form of a push rod 16 is connected to the end 18 of the hydraulic master cylinder 14 (FIGS. 3-6).
(Figure) so that it can reciprocate. The hydraulic master cylinder is closed by an end cap (not shown) with a suitable central opening through which the push rod 16 passes. The end of push rod 16 is connected to a piston (not shown) operatively disposed within master cylinder 14 . As the piston moves, a portion of the hydraulic fluid in front of the piston is routed through a tubular conduit (not shown) to a driven cylinder, such as a wheel brake driven cylinder in a hydraulic brake system, or to a mechanical declutching cylinder. It is delivered to a driven cylinder that operates the mechanism. The end of the master cylinder 14 through which the reciprocating push rod 16 passes is, in conventional construction, typically protected by a boot of elastomeric material. In the construction of the present invention, the elastomeric material boot is omitted in favor of the switch housing 12. This switch housing is screwed on,
It may be attached to the hydraulic master cylinder 14 near the end 18 using any conventional means, such as gluing. In the illustrated structure, the peripheral surface of master cylinder 14 is provided with a circumferential annular groove 20 adjacent to end 18 thereof. The switch housing 12 also has a cylindrical recess 2 with an annular edge 24 at the end.
2. Said annular rim 24 protrudes from the inner surface of the recess 22 and resiliently engages the groove 20 such that the switch housing 12 fits onto the circumferential surface of the master cylinder 14 near the end 18. ing.

Switch housing 12 includes a cylindrical cavity 26. This cylindrical cavity is closed at one end by an end cap 28 with a central opening 30. A body 32 of a plunger 34 is slidably disposed within the central opening. Plunger 34, also made of insulating plastic material, includes an integral radially disposed plunger portion 36. The plunger 34 has a central hole 38 through which the push rod 16 can pass loosely.
It is equipped with The opposite end of switch housing 12 is closed by an end wall 40 that is glued or heat welded. This end wall is provided with a central opening 42 through which the push rod 16 can freely pass.
A return coil spring 44 is provided and surrounds the push rod 16. One end of the coil spring 44 engages the end wall 40. The opposite end of this coil spring also engages the bottom of an annular recess 46 located within the body 32 of the plunger. Annular recess 4
6 is a recess that serves as a guide means for the coil spring 44 and does not prevent the coil spring from retracting when compressed (FIGS. 4 to 6) and completely moving the plunger 34. I work as a place. Therefore, the switch 10 can be made relatively short in length. Two sets of independently longitudinally disposed stationary contacts 48 and 50 and 49 and 51 are mounted within recesses in a portion of the inner surface of the cylindrical cavity 26 of the switch housing 12. Fixed contacts 48 and 50 are spaced approximately 180 degrees apart from each other. Further, the contacts 49 and 51 are arranged in the same manner. The fixed contact 48 is connected to the wiring 52
is connected to the terminal 54 through the fixed contact 50
is connected to a terminal 58 through a wiring 56.
Terminals 54 and 58 are within connector 61. This connector 61 is attached to the end of the end cap 28 of the switch housing, as shown, for example. Fixed contact 49 is connected to terminal 55 through wiring 53. In addition, the contact 51
is connected to a terminal 59 through a wiring 57. Terminals 55 and 59 are also located within connector 63,
For example, the structure shown is attached to the end of the end cap 28 of the switch housing.

Plunger end flange 36 includes a pair of mutually aligned radial holes 60 and 62 (FIGS. 3-6). A sliding brush contact 64 is slidably disposed within the radial bore 60. Similarly, the sliding brush contact 66 is connected to the radial hole 62.
located within. The brush contacts 64 and 66 are
They are partially pressed outward by coil springs 68 and 70, respectively. Means, for example a key and keyway arrangement, as indicated by the reference numeral 72 in FIG. , allowing only relative vertical movement between the plunger flange and the switch housing. The two sliding contacts 64 and 66 are connected to each other by wiring, as indicated schematically by reference numeral 74 in FIG. The sliding contacts 62 and 64 therefore close the circuit of the fixed contact pair 49 and 51 (FIG. 4) or close the circuit of the fixed contact pair 48 and 50 (FIGS. 5 and 5) depending on the linear position indicated by the plunger flange 36. 6
When the circuit shown in the figure) is closed, the electric circuit connecting terminals 55 and 59 or the electric circuit connecting terminals 54 and 58 is closed, respectively. At the position shown in Figure 3, that is, the return position (original position),
Both circuits are opened when sliding contacts 64 and 66 pass over the tips of fixed contacts 49 and 51 and suitably contact portions 76 and 78 at the surface of cylindrical cavity 26.

Switch plunger 34 has an annular end surface 80. This annular end face can engage an annular abutment 82 provided on the push rod. The annular abutting portion 82 can be adapted to abut against the end face of a collar 83 (see FIG. 8) fixed around the push rod 16. The elongate rod 84 has a hole 86 at its opposite end (FIGS. 1 and 1a) for swivel connection to a brake control pedal or a clutch control pedal (not shown). The elongated rod 84 may be provided by any conventional means, such as the elongated rod 84.
Pressure fit the tubular end of the push rod 16,
Alternatively, it is connected to the push rod 16 by screwing, brazing, or caulking.

The annular abutment 82 may also be in the form of the end of a spacer disposed between the end of the elongate rod 84 and the annular end surface 80 of the plunger, or may engage or engage the annular end surface 80. It may be in the form of a spring clip that is snapped into place around the rod 16 proximate the end face 80.

In a mechanical clutch hydraulic control system using the present invention, when shifting gears, slightly pressing the clutch pedal, and depressing the clutch pedal, the cruise control mechanism
control mechanism), connect terminals 55 and 59 of connector 63 to the first
Connect to the cruise control disconnect circuit as schematically shown in the figure. The plunger 34 then moves the sliding brush contacts 64 and 66 from the position shown in FIG.
and 51 (Fig. 4).
Immediately, the cruise control cutoff circuit is closed and cruise control is suspended. Further depression of the clutch pedal causes the annular abutment 82 to further move the switch plunger 34 to a position (FIG. 5) in which the circuit connecting terminals 54 and 58 is closed. When terminals 54 and 58 of connector 61 are connected to the engine start motor relay circuit, the start motor relay circuit is energized so that the vehicle operator can start the vehicle engine. The position of plunger 34 that engages sliding brush contacts 64 and 66 with fixed contacts 48 and 50 leading to terminals 54 and 58 corresponds to the position of the clutch pedal that fully disengages the clutch. However, fixed contacts 48 and 50
has a relatively long length compared to the lengths of contacts 49 and 51. This length is, for example,
This corresponds to the entire stroke of the clutch pedal from the start of clutch release until the clutch pedal hits the floor, that is, the entire stroke of the master cylinder push rod 16. These positional relationships are schematically shown in FIGS. 5 and 6, respectively.

If the vehicle is not equipped with a cruise control device, the structure of the switch 10 can be left as is. Terminals 54 and 58 are left without electrical connections, but can be utilized if the vehicle is later equipped with a cruise control system.

Switch 10 is connected to the hydraulic brake system (first
When installed at the end of the master cylinder 14 in Figure a), the terminals 54 and 58 of the connector 61 are connected in series to the stop signal light emitting circuit of the vehicle. Also,
Since the contacts 49 and 51 are provided extending longitudinally on the surface of the cylindrical cavity 26 of the switch housing 12, the stop signal light continues to be emitted regardless of the position of the brake control pedal. However, as shown, two independent pairs of contacts 49 and 5
By installing switches 1, 48, and 50, the switch 10 can be used for various purposes. Therefore, management of parts is reduced. In addition, the terminal 55 of the connector 63
and 59 and the terminals 54 and 58 of the connector 61 can also be connected in parallel to a common junction of these terminals connected in series to each other and to the stop signal lighting circuit. With this configuration,
The stop signal light will remain on as long as the brake pedal is pressed. In this case, fixed contacts 48 and 4
Insulating portions 88 and 90 of the surface of the cylindrical cavity 26 between the fixed contacts 50 and 51, respectively,
Because it is narrower than the width of the sliding brush contacts 64 and 66,
As the sliding contacts 64 and 66 pass through the insulating portions 88 and 90 of the cylindrical cavity 26, they simultaneously become engaged with the contacts 48 and 49 on the one hand and with the contacts 50 and 51 on the other hand. Further, due to the structure of the switch 10 having two independent pairs of fixed contacts, for example, the terminals 55 and 59 of the connector 63 can be connected to a stop signal light emitting circuit of a different color such as amber or yellow (stop signal No. 1). By connecting the terminals 54 and 58 of the connector 61 in series to the red stop signal light emitting circuit (stop signal No. 2), a progressive warning system for automobile brake operation can be provided. The terminals 55 and 59 of the connector 63 are also used to connect to the cruise control cutoff circuit (Fig. 1a), so that when the driver of the vehicle applies the brakes or slightly depresses the brake pedal, the cruise control system It is also possible to stop the operation.

Instead of the cylindrical configuration shown in FIGS. 1-7, switch housing 12 may have any other configuration, such as switch 10' shown in FIGS. 8 and 9. switch 1
0' housing 12 includes a generally cylindrical peripheral surface portion 92 (FIG. 9) and a generally flat side surface portion 94 (FIG. 9).
(Figure). The housing 12 of the switch 10' is otherwise similar to the previously described embodiments except that the cylindrical cavity and plunger in the previously described embodiments have a cylindrical portion of less than 360 degrees. It houses a switch assembly identical to that of FIGS. 3-7. switch 10'
The housing 12 is laterally snap-fitted onto the master cylinder 14 near the end thereof. The housing 12 of the switch 10' is provided with a longitudinal slot 96 through which it can be passed laterally over the push rod 16 of the master cylinder. In addition, the flange switch 34 is approximately U-shaped, and the push rod 1
It surrounds about half of the circumferential surface of 6.
The housing 12 of the switch 10' has wings 9
A generally U-shaped end recess 98 is provided. The wing elastically expands and is pushed into a portion of the peripheral surface of the cylinder 14 in close proximity to the end of the cylinder 14, and elastically returns to cover the end of the master cylinder 14 so that the housing 12 Can be fitted with snaps.

It will be obvious to those skilled in the art that the present invention encompasses other structures in addition to those shown in detail in FIGS. 3 to 7 and described above. Also, instead of being attached to the end of the master cylinder 14, the electric switch may be attached to the push rod 16 itself, as shown in FIGS. 10 to 14.

The electric switch 10'' of FIGS. 10-14 includes a housing 12 made of plastic. The housing 12 has a pair of wings 102 and a
It has a branch part forming 04. Between the wings a partially cylindrical recess with a cylindrical surface 106 is formed. The cylindrical surface 106 allows the housing 12 to be pushed from the side by the rod 16.
The housing 12 extends over an arc of slightly more than 180 degrees so that the wings 102 and 104 can be elastically spread out to attach the housing 12 to the push rod 16 when pushed into the housing 16 . The end of the housing 12 abuts an annular abutment 82 formed, for example, at the end of a push rod extension 84. plunger 3
4 protrudes from the opposite end of the housing 12. Additionally, the end surface 108 of the plunger 34 normally abuts the lid plate 110 at the end 18 of the master cylinder 14 through which the push rod 16 reciprocates.

Although the outer surface of the end plate 110 of the master cylinder 14 is shown to be in the same plane as the end of the housing of the master cylinder 14 for ease of discussion of the present invention, in normal construction the lid The plate is slightly recessed from the end of the cylinder. Plunger 34 reciprocates through end hole 112 of housing 12 . A longitudinal key 114 (FIG. 11) integrally formed in the body of the plunger 34 engages an opposing longitudinal groove 116 in the housing 12 so that the plunger 34 moves reciprocally. Prevents rotation around the axis.

Plunger 34 is tube-shaped and includes an axially arranged guide pin 118. A coil spring 120 is arranged around this guide pin 118. One end of the coil spring 120 engages a bottom wall 122 of the tubular plunger 34. The opposite end of the coil spring 120 also engages an end wall 124 of the housing 121. An integral short guide pin 126 protruding from the end wall 124 of the housing is disposed coaxially with the guide pin 118 inside the coil spring 120.

The end of the tubular plunger 34 has a metallic ring 128 attached thereto. An annular ring 128 supports or is made integral with a pair of spring sliding contacts 64 and 66. The function of these sliding contacts is the same as brush contacts 64 and 66 in the embodiment of FIGS. 1-7. A cavity in the housing 12 is provided with two separate pairs of fixed contact plates 49 and 5.
1, 48 and 50. The functions of these fixed contact plates correspond to the two pairs of contacts 49 and 51 and 48 and 50 in the embodiment of FIGS. 3 to 7.
is the same as Contacts 49 and 51 and 48 and 50
is connected to a four-legged pin or four-legged socket plug 130 (FIGS. 10 and 11) through a suitable conductor (not shown) recessed within the housing 12 and shown in FIGS. Switch 10'' is adapted to be connected to appropriate control circuitry as described in detail above in connection with the example.

FIG. 12 shows the return position of the plunger 34 relative to the fixed contacts 49 and 51 and 48 and 50, i.e. connected to each other, when the push rod 16 of the master cylinder is fully extended and the switch 10'' is open. The return position of the sliding contacts 64 and 66 is schematically illustrated.As soon as the push rod 16 begins to move under the action of the clutch or brake pedal, the lid plate 1 of the master cylinder 14
The plunger 34, which ends against 10, is forced into the cavity of the housing 12 against the pressure of a spring 120. As a result, sliding contacts 64 and 66, which are connected to each other through metal annular ring 128, connect the circuit across fixed contacts 49 and 51 (FIG. 13). Further movement of plunger 34 within the cavity of housing 12 causes sliding contacts 64 and 66 to contact fixed contacts 48 and 50. The fixed contacts 48 and 50 are located near the end of the allowable retraction distance of the plunger 34, as shown in FIG. 14, and the ends of the pins 118 and 126 collide.

Although the present invention has been described with reference to an exemplary structure configured to achieve the objectives of the present invention, modifications to this exemplary structure will be apparent to those skilled in the art.

[Brief explanation of the drawing]

FIG. 1 is a partial front view of a hydraulic master cylinder and input member assembly for a clutch hydraulic pressure control device equipped with an electric switch according to the present invention. FIG. 1a is a view similar to FIG. 1 showing a master cylinder and input member assembly for a hydraulic brake system. Figure 2 shows 2-2 in Figure 1.
It is an end view seen from a line. Figure 3 is 3 in Figure 2.
- It is a longitudinal cross-sectional view seen from line 3. Figures 4 to 6
The figure is a diagram similar to FIG. 3, illustrating the operational stages of the invention. FIG. 7 is a sectional view taken along line 7--7 in FIG. 3. 8 and 9 are views similar to FIGS. 1 and 2, respectively, and illustrate a modification of the invention. FIG. 10 is a diagram similar to FIG. 1 and shows another modification of the present invention. FIG. 11 is an end view taken along line 11-11 in FIG. 10. Figure 12 shows 12- in Figure 10.
12 is a vertical cross-sectional view along line 12. FIG. Figure 13 and 1
FIG. 4 is a diagram similar to FIG. 12, illustrating the operation of the illustrated embodiment of the invention. 10...Electric switch, 12...Housing,
14...Master cylinder, 16...Push rod, 18
... End of master cylinder, 20 ... Circumferential annular groove, 22 ... Cylindrical recess, 24 ... Annular edge, 26
... Cylindrical cavity, 28 ... End cap, 30 ...
Center opening, 32... Main body of plunger, 34...
Plunger, 36...flange portion, 38...center hole, 40...end wall, 42...center opening, 44...
... Return coil spring, 46 ... Annular recess, 48,4
9, 50, 51... fixed contact, 52, 53... wiring, 54, 55... terminal, 56, 57... wiring,
58, 59... terminal, 60, 62... radial hole, 61, 63... connector, 64, 66... sliding brush contact, 68, 70... coil spring, 72
... Structure of key and keyway, 74 ... Wiring, 76,
78... Portion on the surface of the cylindrical cavity of the housing, 80... Annular end surface, 82... Annular contact portion, 8
3...Color, 84...Elongated rod, 86...Hole,
88, 90...Insulating part.

Claims (1)

[Claims for Utility Model Registration] (1) An electric switch provided in a hydraulic master cylinder having a linearly movable input member, wherein the electric switch is configured such that the input member moves from an original position to an operating position. the electrical switch includes a pair of movable elements and a pair of fixed elements, the movable elements being in an inoperable relationship with respect to the fixed elements. The movable element is adapted to be moved by the input member from a first position to a second position cooperating with the fixed element, the first position of the movable element returning to the original position of the input member. and the second position of the movable element corresponds to the starting point of the working position, and from the starting point of this working position to the end of this working position the movable element is connected to the fixed element. furthermore, said electrical switch is adapted, in use, to control an electrical circuit comprising said fixed element or said movable element, said movable element controlling said second position and cooperates with said fixing element, said fixing element extending into a housing mounted on said cylinder or carried by said input member. a plunger that engages a stationary portion of the master cylinder, the movable element being a plunger that extends into a housing mounted on the cylinder, or a plunger that engages a stationary portion of the master cylinder; An electric switch, characterized in that it is provided in a housing carried by a carrier. (2) A device is provided for returning the movable element to the first position, and when the input member returns to the original position, the movable element is automatically deactivated relative to the fixed element. Becoming moved to be in a relationship,
An electric switch according to claim 1 of the utility model registration claim. (3) includes a second pair of movable or fixed elements, which in use are included in a second electrical circuit and which are inoperative when said input member is in its original position; and the elements of the second pair are arranged in a manner such that upon further movement of the input member from the first operative position of the input member in which the movable element and the fixed element of the first pair cooperate. providing a second operative position of the input member, such that the second pair of movable or fixed elements cooperates with the first pair of fixed or movable elements;
An electric switch according to claim 1 or 2 of the utility model registration claim. (4) The electric switch according to any one of claims 1 to 3, wherein the master cylinder forms part of a hydraulic system of a vehicle. (5) The electric switch according to claim 4, wherein the hydraulic device is a brake device, and the electric circuit is a stop signal circuit. (6) The electric switch according to claim 5, wherein the electric switch is adapted to control two electric circuits, both of which are stop signal circuits. (7) The electric switch according to claim 5, wherein one of the first pair of elements and the second pair of elements is included in a third electric circuit. (8) The electric switch according to claim 7, wherein the third electric circuit is a cruise control cutoff circuit. (9) The electric switch according to any one of claims 4 to 8, wherein the hydraulic device is a hydraulic clutch control device. (10) said electric switch is adapted to control an interlock circuit of a starting motor relay;
An electric switch according to claim 9 of the utility model registration claim. (11) The electric switch according to any one of claims 1 to 10, wherein the fixed element is an electric contact. (12) The electric switch according to any one of claims 1 to 11, wherein the movable element is an electric contact.