US2990917A - Self-adjusting take-up means - Google Patents

Description

July 4, 1961 W. STELZER SELF-ADJUSTING TAKE-UP MEANS 2 Sheets-Sheet 2 Filed Oct. l5, 1959 INVENTOR W/LL/AM STELZER ATTORNEY United yStates Patent 2,990,917 SELF-ADIUSTING TAKE-UP MEANS William Stelzer, Bloomfield Hills, Mich., assigner to Kelsey-Hayes Company, Detroit, Mich., a corporation of Delaware Filed Oct. 15, 1959, Ser. No. 846,633 11 Claims. (Cl. 18S-1) This invention relates to` a self-adjusting take-up means and more particularly to a device for taking up play between otherwise relatively movable elements to eliminate the use of shims. The device is disclosed, but not claimed, except in combination with a fluid pressure motor mechanism, in my copending 'application Serial No. 845,250, filed October 8, 1959, for a Fluid Pressure Motor Mechanism.

In my copending application referred to, I have disclosed a fluid pressure motor mechanism particularly adapted for use as a booster mechanism for motor vehicle brakes. The device includes means, in the form of levers, for transmitting to the vehicle brake pedal reaction forces occurring incident to resistance to movement of a fluid pressure unit of the motor when brake line pressures increase. The device forming the subject matter of the present invention is utilized in such combination to take up play between the reaction levers and the elements with which such levers contact. The take-up device is not limited in its use to uid pressure motors of the type referred to but is capable of general use for taking up play between parts instead of using shims.

An important object of the present invention is to provide a novel device adapted to be arranged between otherwise relatively movable elements spaced from each other and wherein the spacing of such elements varies in accordance with manufacturing tolerances, the present device eliminating the necessity for measuring distances between the otherwise relatively movable elements to determine the number and thickness of shims to be used between such elements, the shims being completely eliminated.

A further object is to provide a novel take-up device which is adapted to bridge a gap of definite Width between two elements for the transmission of force between such elements or two other elements by utilizing a novel deformable type of play take-up means which completely eliminates the use of shims.

A further object is to provide la device of the nature referred to wherein the take-up device is formed of an over-all thickness greater than the gap which it is adapted to fill, and to so form the take-up device that it adapts itself to the width of the gap in which it is arranged upon the application of force tending to move the relatively movable elements toward each other.

A further object is to form the take-up device of a ductile material, such as soft steel plate, .which has the characteristic of being deformable and of taking a set in its deformed shape whereby, when the relatively movable elements between which the device is arranged have been moved toward each other to reduce the gap therebetween to its normal Width, the take-up device will iill such gap and will not exert any force tending to move the elements away from each other.

In the drawings I have shown one embodiment of the invention. In this showing:

FIGURE l is an axial sectional View through a motor mechanism and associated parts, showing the present invention in one of its possible uses;

FIGURE 2 is an enlarged fragmentary sectional view showing a portion of one of the take-up devices with certain elements thereof in their original shapes, the device in `the prisent instance being shown between por- Patented July 4, 1961 tions of 'a pressure responsive motor unit illustrated in FIGURE 1;

FIGURE 3 is a view similar to FIGURE 2, showing the parts in positions which they may assume after the mechanism has been placed in operation;

FIGURE 4 is a detailed face View of the play take-up device per se;

FIGURE 5 is a detailed sectional view on line 5-5 of FIGURE 4; and

FIGURE 6 is a fragmentary detailed sectional vie on line 6--6 of FIGURE l.

As previously stated, the device forming the subjectmatter of the present invention has been illustrated in detail in one of its possible uses, namely, as a play take-up means between parts of a fluid pressure motor mechanism. Such mechanism (FIGURE l) is indicated as a Whole by the numeral 10 and comprises casing sections 11 and 12, secured together as at 13, having a die-cast body 15 axially therein provided with an en larged head 16 connectedas described below to spaced` pressure responsive units forming a part of the motor.

The motor is divided into two units by a wall 17 com` prising a stamped shell 18 the inner periphery of which is connected as at 19 to the outer periphery of a diaphragm 20. Such diaphragm is secured to the body por-V tion 16 as at 21, while the outer periphery of the shell. 18 is secured'in a manner to be described to the casing section 12.

One pressure responsive unit of the motor is indicated as a whole by the numeral 24 and comprises a stamped plate 25 shaped as shown in FIGURE l and connected at its inner periphery to the body member 16. The outer periphery of the plate 25 is secured by a welded ring 28 to the inner periphery of a diaphragm 29 of theY rolling type. The outer portion of such diaphragm contacts with a shell 3 0, the outer periphery 31 of 4which retains in position a bead` 32 formed on the outer periphery of the diaphragm 29. Inwardly extending bosses 34 on the shell 30 space the latter from the shell 18 to form therebetween a flui-d passage or passages 35 (see. the bottom of FIGURE l) communicating with a varia-l ble pressure chamber 36 between the unit 24 and dividing wall 17.

The second pressure responsive unit Vis indicated as a whole by the numeral 40 and comprises a stamped platel 41 engaged against a portion of a diaphragm 42 having, its outer periphery formed with a bead 43. The shell 18 has a cylindrical portion 44 provided with a radially outturned flange 45 seating in the -bead 43. The pressure responsive unit 40 forms with the casing section 12 a second variable pressure motor chamber 46. The radially outer and right-hand faces of the diaphragm bead 43 (FIGURE 1) are grooved as at 47 (FIGURES 1 and 6i) to afford fixed communication between the motor chamber 46 and the passage 35. Accordingly, the two variable pressure chambers36 and 46 are in fixed communication with each other. Y y

The inner periphery of the plate 41 extendsl cylindrically in one direction as at 50 and terminates in a radially inwardly extending flange 51 overlying and spaced from the peripheral portion of .a preferably cast plate V52 hav.- ing bosses 53 secured to the body portion 16 by screws 54. Accordingly, the plate 52 is axially movable with the cast member `15. The inner periphery of the diaphragm"42 is fixed as at 55 to the plate 52. It will become apparent that initially the flange 51 and plate 52 constitute relatively movable members for transmitting differential pressure forces developed when pressure is admitted to the motor cham-ber 46. Because of the cooperative 'relation between the flange 5-1 and other elements to be described, and due to manufacturing tolerances, the space between the ange 51 and the periphery of the plate 52 is variable.

In accordance with common practice, therefore, it is necessary in each installation to measure play between the flange 51 and plate 52 and select shims to be arranged therebetween to fix the play between such elements to prevent relative movement therebetween in operation. The device forming the principal subject matter of the present invention comprises a play take-up member indicated as a whole by the numeral 58 which voperates automatically after the device has been placed in operation to fix the distance between the elements 51 and 52 without the expensive loss of time required for measuring and inserting shims in the manner stated. The play take-up member 58 will be described in detail later.

An axially movable member 60 has one end slidable in a bore 61 formed in a sleeve portion 62 preferably integral with the plate 52. The sleeve portion 62 is axially slidable in a combined bearing and sealing unit 63 carried by the casing section 12. The inner end of the member 60 slides in a bore 64 formed in the body portion 16. The member 60 is provided intermediate its ends With an annular valve seat 65 inwardly of which the member 69 is provided with radial ports 66 communicating with a bore 67 in the member 60, which bore is always in communication with the atmosphere as described below.

An axially extending force transmitting member 70 is carried by the body and has a passage 71 open at one end to the passage 67. A spring 72 biases the member 60 toward the right in FIGURE 1. The casing section 11 has a hub portion 75 carrying an air cleaner 76 inwardly of which is arranged a bearing 77 in which the projection 70 is slidable. Such bearing is in the form of a split ring and is provided with longitudinal grooves 78 and radial grooves 79 4for the free ilow of air through the air cleaner, through stamped grooves 80, and thus into the passage 71.

The projection 70 engages at its left-hand end (FIG- URE 1) against a plunger 82 of a conventional vehicle master cylinder 83 to operate the latter. To facilitate the ow of air into the passage 71, the projection 70 is notched as at 85. The air cleaner 76 is retained in position by a plate 90 carried by the casing section 11 and secured to the master cylinder by screws 91.

In the body portion 16 is formed a relatively large chamber 95 communicating as at 96 with a constant pressure chamber 97 formed between the pressure responsive unit 24 and the casing section 11. The body portion 16, within the chamber 95, is provided with an annular valve seat 98 concentric with and surrounding the valve seat 65.

A valve body 99 is supported by the member 60 by means of a diaphragm 100, and a resilient valve element 101 is carried by the valve body 99 and normally engages the seat 65. The valve element is normally disengaged from the valve seat 98 and is urged to the left in FIGURE 1 by a spring 102.

Between the bosses 53, the body member 16 has circumferentially spaced recesses 105 in each of which is arranged a resilient lever fulcrum cushion 106. A reaction lever 108 engages intermediate its ends with each cushion 106 and has its outer end engaging the ange 51. The radially inner end of each lever is arranged in a recess 111 formed in the member 60. Due to the action of the take-up device 58, the cushions 106 serve to maintain each outer lever end in engagement with the flange 51 While the inner ends of the levers are maintained in engagement with the shoulder formed at the right-hand end (FIGURE 1) of the groove 111.

A Wear plate 112 is arranged against the right-hand end (FIGURE 1) of the body member 16 and is engageable by the adjacent portion of each lever 108 after the fulcrum members 106 are deformed in the operation of the device.

The pressure responsive unit 24 is urged to normal off position by a return spring 115. The space between the wall 17 and pressure responsive unit 40 forms a constant pressure motor chamber 117 in which is arranged a combined counter-reaction and return spring 118.

To the left of the valve seat 98 (FIGURE l) and around the adjacent portion of the member 60 is formed a chamber 120 normally communicating with the chamber 95. A passage 121 connects the chamber 120 with the motor chamber 36. Accordingly, pressure in the chamber 120 is always present in the motor chambers 36 and 46.

The member 60 is actuated by a push rod 125 connected to the vehicle brake pedal (not shown) to be operated thereby. The push rod 125 is connected to the member 60 by a spherical head 126 back of which is a rubber washer 127 to permit limited rocking movement of the rod 125.

The motor in the present instance is vacuum suspended and the chamber 97 is accordingly connected to a source of vacuum preferably through a check valve device forming no part of the present invention but disclosed and claimed in my copending application Serial No. 810,340, filed May l, 1959. This check valve comprises a body 130 having a chamber 131 communicating with the interior of a nipple 132 connected to the vacuum source. The body 130 is connected as at -133 to the casing section 11, which is ported as at 134. Such ports are normally closed by a resilient check valve 135 biased to closed position by a spring 136.

The self-adjusting spacer 58 is shown in FIGURE 1 in the form in which it is initially installed. The device has been illustrated in the present case as a means for taking up play between the ange 51 and plate 52, thus consequently taking up play between the ilange 51 and lever ends 109 to eliminate play between the levers 108 and the three elements with which each lever is engaged. So far as the present invention is concerned, the ange 51 and plate 52 constitute elements which, in the absence of the normal functioning of the present invention, are relatively movable because of play therebetween, and which play is adapted permanently and automatically to be taken up by the spacing member 58. Regardless of the particular elements between which the present device is arranged, it will be apparent that it eliminates the use of shims, the number and thickness of which must be determined by measurement, as stated above.

Referring to FIGURES 2-5, inclusive, the member 58 is made of ductile metal such as soft steel plate so that elements of the member 58 to be described will yield under pressure and then take a set to predetermine the spacing between the elements with which the device is employed. The member 58 is shown in the present instance as a split ring (FIGURE 4) radially notched as at to provide fingers 141 normal to the plane of the material from which the plate is formed. Such ngers alternate with ngers 142 which are initially bent as shown in FIGURES l, 2 and 5 so that the over-all thickness of the spacer is greater than the final space to be determined between the elements with which the device is used. In the present instance, the remaining portions of the member 58 preferably have their edge portions chamfered as at 143 to seat, if necessary, against the ange 51, the radially inner portion of which is connected to the cylindrical plate portion 50 through a lleted corner. In the present instance, the member 58 has been shown as being cut away as at '145 to save material, but it will be apparent that the member 58 may be a continuous ring. Also, the device has been illustrated with three sets of three each of the lingers 142, such sets of lingers being equidistantly spaced circumferentially of the device. Depending upon the force to be transmitted by the device, more or less than three ngers 142 may be employed in each set. Where substantial force must be transmitted, the fingers 142 could be used around the entire periphery of a member 58 formed as a ring. The device shown in FIGURE 4 has been designed for a particular purpose so that the fingers 142, when -bent out of their original shapes as described below, will take a set in such bent shapes and will transmit all of the force necessary.

Operation The invention forming the subject matter of the present application has been shown only incidentally in conjunction with a fluid pressure motor, and as stated above, the device is capable of use in many places where shims ordinarily are employed. Since the motor is shown only incidentally, and is described in detail in my copending application referred to above, its operation need not be described in detail. Normally, the motor chambers 36 and 46 are cut ott from the atmosphere at the valve seat 65, and accordingly vacuum will exist in all four motor chambers. Operation of the rod 125 moves the member 60 to the left in FIGURE 1 to -irst permit the valve 101 to engage the seat 98 and then open the Valve seat 65. This operation disconnects the chamber 126 from the vacuum chamber 95 and opens it to the atmosphere through the passage 67, whereupon air will be admitted to the motor chamber 36 and through passages 35 and grooves 47 to the chamber 46. Accordingly, both pressure responsive units will start to move to the left and the unit 24 delivers its power directly and positively to the member and projection 71) to operate the plunger 82. The unit 401 transmits its force through the levers 108 assisted by pedal operation. During initial motor energization the sprin-g i118 absorbs the force of the unit 40 and the levers 108 do not turn appreciably and the reaction to the pedal is very light. However, when sufficient resistance to movement against the plunger 82 occurs, the unit 441 tends to compress the spring 118 and move to the left relative to the body 216 to rock the levers 108 and transmit reaction forces through the rod 125 to the brake pedal (not shown). In the present use of the take-up device 58 it is important that the outer lever ends 109 be maintained in contact with the flange 51; that the fulcrum points of the levers 108 be maintained in contact with the cushions 106 and that the inner lever ends 110 contact with the right-hand end (FIGURE l) of the groove 111. Thus there is no play between the levers 168 and the elements wit-h which they are engaged, and this has been found in the present installation to eliminate any tendency for the valve mechanism to flutter. Moreover, reaction forces will be transmitted to the rod 125 promptly upon initial compression of the spring 118 by movement of the pressure responsive unit 40.

In assembling the parts it is unnecessary to accurately measure the space which will occur between the flange 51 and plate 52 when play is 4taken up between the levers 108 and the elements with which they are engaged. The spacer 58 is inserted in position as shown in FIGURES l and 2 with the fingers 142 engaging the liange 51 and urging the latter away from the plate 52. When the pressure responsive unit 40 is assembled relative to the body portion 16, therefore, more than normal f orce will be transmitted between the levers 108 and the cushions 106 than would occur after the device has been placed in operation as described below, and accordingly the cushions 106 will be initially deformed.

After assembly of the elements, the operation of the motor as described above will cause the lever ends 109 to` exert substantially greater force against the flange 51, and this element accordingly will be moved toward the plate 512 to bend the fingers 142 to some shape intermediate the shapes shown in FIGURES 2 and 3, the latter shape being assumed if, in an extreme case, the normal space between the flange 51 and plate 52 should be equal to the thickness of the body portion of the spacer 5S. In practically every installation, however, a slight bend will remain in the lingers 142.

Such normal initial operation of the motor will cornpress the cushions 106 and cause the bending of the lingers 142 as described. The stoclc thickness or strength of the lingers 142 is such that they are obviously weaker than the levers 108 and yet strong enough to maintain the desired over-all thickness by forcing the compression of the cushions 106 to the extent which will occur during normal motor operation. Having been thus bent to a shape intermediate the shapes shown in FIGURES Z and 3, the fingers 142 will take a set and maintain a proper spacing between the ange 51 and plate 52.. I n subsequent operation, therefore, the lingers 142 serve t0 properly space the members 51 and SZ and tov keep the former in engagement with the lever ends 109` and to maintain each lever in contact, when the parts are in off positions, with the cushions `1116 and the shoulder of the groove 1-11. Further normal operations will not further bend the lingers 142 and they retain their initial bent shape throughout the life of the apparatus. While the invention has been shown in conjunction with a particular type of tluid pressure motor reaction means, it will be apparent that it is not in any sense limited to such use. The device may be utilized as an automatic play take-up means to x the relative positions of otherwise relatively movable elements. For example, direct forces could be transmitted from the plate 52 to the body member 16 through the use of the device 58, it being entirely possible to maintain a fixed position between the members 52 and 16 without any play therebetween when such parts are in normal 0E positions. Accordingly, it will be apparent that the present device is capable of use in numerous mechanical constructions. In the claims, therefore, reference is made to otherwise relatively movable elements between which play is to be taken up by the present device. Such elements could comprise, for example, the plate 52 and ange 51, or the plate 5'2 and lever ends 109, -the plate 52 and body portion A16, etc.

It is to be understood that the form of the invention shown and described is to be taken as a preferred example of the same and that various changes in the shape, size, and arrangement of the parts may Ibe made `as do not depart from the spirit of the invention or the scope of the appended claims.

I claim:

1. In a play take-up means, a pair of members having spaced portions, and -a play take-up device formed of sheet material arranged between such portions and having a body engaging one of such portions, said device having integral elements extending angularly relative to said body and engaging the other portion, said device being formed of a material adapted to be bent and then take a set whereby, Iwhen a predetermined force -is exerted relatively against said portions to move them toward each other, said elements will be bent and take a set to predetermine the spacing of said portions.

2. In a play take-up means, a structure having `a pair of spaced annular portions, and a ring-like play take-up member formed of sheet material arranged between said portions and having a body seated against one of said portions, said member having circumferentially spaced integral elements extending from said body and engaging the other of said portions, said member being formed of ia material adapted to be bent `and to take a set when bent whereby, upon the application of a predetermined force tending to move said annular portions toward each other, said elements will be bent to predetermined positions relative to said body and take a set in such positions 'to predetermine the spacing between said annular portions.

3. In a play take-up means, a structure having a pair of spaced annular portions parallel to each other and one of which portions has a ilat face, and a play take-up member yarranged between said annular portions and having a flat ring-like body `seated against said dat face, said member having circnmferentially spaced fingers extending angularly out ot the plane of said body and engaging the other annular portion, said member being formed of a material adapted to be bent and to assume a set when bent whereby, upon the application of a predetermined force to said annular portions to move them toward each other, said fingers will be bent to predetermined positions and take a set in such positions to predetermine the spacing of said annular portions.

4. In a play take-up means, a pair of members having spaced portions, a take-up device formed of sheet material arranged between such portions and having a body engaging one of such portions, said device having elements extending angularly relative to said body and engaging the other portion, and means operative for exerting a predetermined force tending to move said portions relatively toward each other, said device being formed of a material adapted to be bent and then take a set whereby, when said portions are subjected to said predetermined force, said elements will be bent and take a set to predetermine the spacing of said portions.

5. In a play take-up means, a structure having a pair of annular portions, a ring-like play take-up member formed of sheet material arranged between said portions and having a body seated against one of said portions, said member having circumferentially spaced integral elements extending from said body and engaging the other of said portions, and means operative for subjecting said portions to a predetermined force to move said portions axially relatively toward each other, said member being formed of a material adapted to be bent and then take a set whereby, upon the application of said predetermined force, said elements will be bent relative to said body and take a set to predetermine the spacing between said annular portions.

6. In a play take-up means, a structure having a pair of spaced annular portions parallel to each other and one of which portions has a flat face, a play take-up member arranged between said annular portions and having a fiat ring-like body seating against said fiat face, said member having circumferentially spaced fingers extending out of the plane of said body and engaging the other annular portion, and means operative for subjecting said portions to a predetermined force Ito move them axially relatively toward each other, said member being formed of a material adapted to be bent and to assume a set when bent whereby, upon the application of said predetermined force to said annular portions, said fingers will be bent and will take a set to predetermine the spacing of said annular portions.

7. In a play take-up means, a structure to which force may be applied to effect movement thereof, said structure having a pair of spaced portions, a play take-up device formed of sheet material arranged between such portions and having a body engaging one of such portions, said device having integral elements extending from said one portion and engaging the other portion, force transmitting means engaging one of said portions and operative for resisting movement thereof when said force is applied to said structure to thereby cause relative movement of said portions toward each other and thus bend said elements, said device being `formed of a material adapted to be bent and then take a set whereby when said elements are bent they will take a set and predetermine the spacing between said portions.

8. In a play take-up means, a structure having a pair of spaced coaxial annular portions and being axially movable, a play take-up member arranged between said portions and having a ring-like body seated against one of said portions, said member having circumferentially spaced ngers extending angularly from said body and engaging t-he other of said portions, force-transmitting means engaging one of said portions to transmit force therefrom upon movement of said structure and to resist such movement with a predetermined force whereby said portions will be relatively moved toward each other to bend said fingers, said member being formed of a material adapted to be bent and then take a set whereby when said portions are relatively moved toward each other, said fingers will take a set to predetermine the spacing between said annular portions.

9. In a play take-up means, a structure mounted for movement on a given axis and having a pair of spaced `annular portions concentric with said axis and spaced longitudinally of said axis, a take-up member arranged between said annular portions and having a ring-like body seated against one of said portions, said member having circumferentially spaced fingers extending from said body and engaging the other annular portion, force-transmitting means engaging one of said portions at uniformly circumferentially spaced positions and movement of which force-transmitting means is resisted whereby when said structure is moved, said force-transmitting means will react against said last-named portion to effect relative movement of said portions toward each other to reduce the space therebetween and bend said fingers, said member being formed of a material adapted to be bent, they will take a set to predetermine the spacing of said annular portions.

l0. A play take-up device comprising a body formed of sheet material having integral elements extending angularly relative to said body to predetermined angular positions, said device being formed of a material adapted to be bent and then take a set whereby, when said elements are subjected to a predetermined force to bend them to different positions relative to said body, they will take a set in said different positions.

11. A play takeeup device comprising a ring-like body formed o-f sheet material having circumferentially spaced integral fingers extending angularly therefrom, said device being formed of a material adapted to be bent and then take a set whereby upon the application of a predetermined force to said fingers to bend them to different angular positions, they will take a set in such positions.

References Cited in the file of this patent UNITED STATES PATENTS

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