AU703336B2 - Tilt type steering apparatus - Google Patents

Description

S F Ref: 334171D2

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

*I

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00 0* 0* F *r 0 0.00 0 0* 0 F F. 0 Name and Address of Applicant: Actual Inventor(s): Address for Service: Invention Title: NSK Ltd.

6-3, Ohsaki 1-chome Shinagawa-ku Tokyo

JAPAN

Tadashi Hibino and Sakae Matsumoto Spruson Ferguson, Patent Attorneys Level 33 St Martins Tower, 31 Market Street Sydney, New South Wales, 2000, Australia Tilt Type Steering Apparatus The following statement is a full description of this invention, including the best method of performing it known to me/us:- 5845 -1- Tilt Type Steering Apparatus BACKGROUND OF THE INVENTION Field of the Invention This invention relates to a tilt type steering apparatus for a vehicle.

Related Background Art There is known a height adjusting apparatus for a steering wheel called the tilt type steering apparatus 10 adapted to be capable of changing the height of a steering wheel in conformity with the constitution, driving posture or the like of a driver. As such a tilt type steering apparatus, there is known one described, for example, in Japanese Utility Model 15 Publication No. 2-34145.

The tilt type steering apparatus described in this publication is called the swing type and is cons-tructed as shown in Figs. 5 to 8 of the accompanying driawings.

A steering column 2 formed into a cylindrical shape to insert a steering shaft 1 thereinto is bisected into a fore steering column 3 and a rear steerina column 4.

These two steering columns 3 and 4 are co:nected together by a support bracket 5 fixily supor tl (I: vehicle body. The rear steering column 4 i; iv ta lly movable about pivot pins 6 and 6 provided concentrically with each other on the support bracket -2- These pivot pins 6 and 6 are :ade into a bolt-like shape and have pillar portions 24 and 24 formed between large-diametered heads 22, 22 formed on the outer end portions thereof and externally threaded portions 23, 23 formed on the tip end portions thereof. The outer diameter of these pillar portions 24, 24 is larger than the outer diameter of the externally threaded portions 23, 23 and is smaller than the outer diameter of the heads 22, 22. The pivot pins 6, 6 are such that with 10 the externally threaded portions 23, 23 threadably engaged with and fastened in threaded holes 25, formed in the rear steering column 4, the pillar portions 24, 24 are positioned in circular holes 26, 26 formed in the support bracket 5. Accordingly, the rear 15 steering column 4 becomes pivotally movable about the pivot pins 6, 6.

A restraining mechanism engageable by a tilt lever 7 pivotally movable about the pins 6, 6 is provided between the support bracket 5 and the rear steerinq column 4. Describing an example of this restraining mechanism in detail, one end of the rear steering column 4 is pivotally supported on the support bracket by the pivot pins 6, 6 provided -n the support bracket 5 fixed to a vehicle body an the undersi i r the like of a dashboard 8, and als: a first engagone,.it: member 9 is fixed to the underside of the rear steering column 4. The underside of this first engagement r -3member 9 forms an arcuately concave surface centering around the pivot pins 6, 6 and first engagement t :eth are formed on this underside.

On the other hand, one end (the left end as viewed in Figs. 6 and 8) of a second engagement member 12 engageable with the engagement member 9 with the pivotal movement of the tilt lever 7 is pivotally supported on a lateral shaft 11 provided on the support bracket 5. Second engagement teeth 13 engageable with

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the first engagement teeth 10 formed on the underside of the first engagement member 9 are formed on the upper edge of the other end portion (the upper edge of the right end portion as viewed in Fig. 6) of the second engagement member 12. A roller 15 is supported 15 on a shaft 14 having its end portion coupled to the lower end portion of the tilt lever 7 having its intermediate portion pivotally supported on the pivot pins 6, 6, and the upper surface of this roller bears against the underside of the second engagement member 12. Further, a pin 18 protruding from the side of the second engagement member 12 is engaged with an inclined slot 17 forned in a rockable plate 16 fixed to the tilt lever 7.

With the construction as described above, when th" tilt lever 7 is pivotally moved in i counter-clockwise direction as viewed in Fig. 6, the roller 15 retracts from below the other end portion (the right end portion -4as viewed in Fig. 6) of the second engagement mn:r.:r 1i2 and at the same time, the other end portico of the, second engagement member 12 is downwardly displaced on the basis of the engagement between the inclined slot 17 and the pin 18. As a result, the engagement between the second engagement teeth 13 formed on the upper surface of the other end portion of the second engagement member 12 and the first engagement teeth on the underside of the first engagement member 9 fixed 10 to the underside of the rear steering column 4 is released (within such a range that a pin 19 projectedly provided on the side of the rear steering column 4 can a be displaced inside an arcuate slot 20 formed in the support bracket 5) and the rear steering column 4 15 becomes pivotally movable about the pivot pins 6, 6.

On the basis of this pivotal movement, the height position of a steering wheel fixed to the end portion of the steering shaft 1 inserted in the rear steering column 4 becomes adjustable.

When the height position of the steering wheel is adjusted in this manner, the tilt lever 7 is pivotally moved in a clockwise directicn as viewed in Fig. 6.

With this pivotal movement, the roller 15 co;es into below the other end portion of the second engagement member 12 and pushes up the other end portion of this second engagement member 12, thereby bringing the second engagement teeth 13 formed or the upper surface of this other end portion into engagement with the first engagement tooth 10 formed on the underside of the first engagement member 9 fixed to the underside of the rear steering column 4. As a result, the rear steering column 4 is prevented from rotating about the pivot pins 6, 6 and holds the steering wheel at its adjusted height position. In this state, a resilient force which tends to pivotally move the tilt lever 7 in the clockwise direction as viewed in Fig. 6 is imparted 10 to the tilt lever 7 by a tension spring 21 and therefore, it does not happen that the roller inadvertently retracts from below the second engagement member 12.

However, in the case of a pivotally 15 supporting apparatus incorporated in the prior-art tilt type steering apparatus constructed and used as .described above and pivotally supporting the fore end portion of the rear steering column 4, the assembling work has been cumbersome and the efficiency of the work of manufacturing the tilt type steering apparatus has been bad. That is, in the case of tho prior-art apparatus, the work of bringing the externally throea.ded portions 23, 23 of the pivot pins into threadable engagement with threaded holes 25, ,i formed in the right and left sides of the rear steering column 4 and fastening them becomes necessary. This threadably engaging and fastening work need be done with a predetermined tightening torque to prevent the pivot pins 6, 6 frc-m being loosened and cominq off or from being too much tightened to thereby damage the threads, and is cumbersome.

In contrast, Japanese Patent Application No. 230026, as shown in Fig. 9 of the accompanying drawings, describes a structure in which a rear steering column 4a is pivotally supported on a support bracket 5a by pivot pins 6a, 6a having large-diametered 10 portions 27, 27 and small-diametered portions 28, 28 connected together by stepped portions 29, 29. In this structure, the large-diametered portions 27, 27 are fitted in and fixed to circular holes 31, 31 formed in the support bracket 5a and reinforcing plates 30, 15 and also, the small-diametered portions 28, 28 are inserted in cylindrical sleeves 32, 32 supported on both side walls of the rear steerirn. column 4a.

Portions of the reinforcing plates 30 are caulked diametrally inwardly of the circular holes 31, 31 to thereby achieve the anti-slippage of the pivot pins 6a, 6a.

In the case of the structure a; shown in Fi i. the work of press.in or inserting qt:e pivr pin ta, -1 into the circu:lar holes 31, 31 and i,-vo: 32:, 32 is easy, but the work of caulking portion: of tho reinforcing plates 30, 30 to prevent the slippane (if the pivot pins 6a, is cumbersome. Pirticulrly, portions of the pair of reinforcinq plates 30, provided with the hollow tubular rear steering column 4a interposed therebetween are caulked and therefore, when the rigidity of the rear steering column 4a is insufficient, it is necessary to achieve the prevention of the deformation of this rear steering column 4a as by inserting a receiving mold into the rear steering column 4a. The work of putting such a receiving mold into and out of the rear steering column is cumbersome 0 and it also makes the efficiency of the work of manufacturing the tilt type steering apparatus bad.

(ii) In the case of the prior-art tilt type steering apparatus shown in Figs. 5 to 8, not only the assembling work has been cumbersome and the efficiency 15 of the work of manufacturing the tilt type steering apparatus has been bad, but also the width dimension thereof has been large and therefore the space for installation has unavoidably been increased. That is, in the case of the prior-art apparatus, the work of bringing the externally threaded portions 23, 23 of the pivot pins 6, 6 into threadable engagement with the threaded holes 25, 25 formed in the right and left sides of the rear steering column 4 and fastenino them becomes necessary. This threadably enlaing and fastening work need be done with a predetermined tightening torque to prevent the pivot pins 6, 6 from being loosened and coming off or from beino too much -8tightened to thereby damage the threads, and is cumbersome. Also, the heads 22, 22 of the pivot pins 6, 6 protrudes greatly from the outer side of the tilt lever 7 and therefore, the maximum width dimension of the tilt type steering apparatus becomes large.

Therefore, in some cases, the design for enabling the apparatus to be installed in a limited space as under the dashboard becomes cumbersome.

(iii) In the case of the tilt type steering apparatus shown in Figs. 5 to 8, it is necessary to provide a spring between the portion fixed to the support bracket 5 and the portion fixed to the rear steering column 4 and support the weight of the portion pivotally moved about lateral shafts 6, 6 with the rear S 15 steering column 4. The reason for this is as follows.

The steering shaft 1 and the steering wheel 25 are *supported on the rear steering column 4 pivotally movable about the lateral shafts 6, 6. Therefore, the weight of the portion pivotally moved about the lateral shafts 6, 6 increases considerably. Accordingly, unless this weight is supported by a spring, as soon as the engagement of the aforedescribed restraining mechanism is released, the rear steerinc column 4 will downwardly rock forcibly to thereby hit a driver's toot: or the like with force. Also, the driver will have to adjust the height position of the steering wheel while supporting this great weight, and the adjustirng work becomes cumbersome.

As the spring for supporting the weiqht of thQt rear steering column 4, use is made of a tension spring or a compression coil spring. When a tension spring is used, this tension spring is disposed on the upper side of the steering column 2. In contrast, when a sufficient space cannot be secured on the upper side of the steering column 2, a compression coil spring is disposed on the lower side of the steering column 2.

10 Figs. 16 and 17 of the accompanying drawings show a prior-art structure in which for such a purpose, a compression coil spring 226 is disposed on the lower side of a steering column 202.

The fore end portion (the left end portion as 15 viewed in Fig. 16) of the compression coil spring 226 resiliently bears against the rear side (the left side as viewed in Fig. 16) of a fixed side receiving pieco 227 secured to a portion of a suppcrt bracket 205 ind downwardly protruding from the fore end portion (the left end portion as viewed in Fig. 16) of the support bracket 205. A bent-up piece 231 is bent up on tho rear side of the fixed side receivinq piece 227 at right angle with respect to this re-ir side. 'The r, end portion of the compression coil sprinr.ri i.s fitted on the bent-up piece 231. T:e rear end portionr (the right end portion as viewed i. Fig. 16) of th, compression coil spring 226 resilien.tly bear3s ,qairi:t the fore side (the left side as viewed in Fig. 16) of a pivotal movement side receiving piece 23; secured to pivotally movable bracket 229 constituting a rear steering column 204a with a column tube 228 and downwardly protruding from the fore end portion (the left end portion as viewed in Fig. 16) of the pivotally movable bracket 229. A circular concave hole 232 is formed in the fore side of the pivotal movement side receiving piece 230 in a direction perpendicular to 10 this fore side. The rear end portion of the compression coil spring 226 is fitted in the concave hole 232. By the compression coil spring 226 being assembled in this manner, this compression coil spring 226 resiliently stretches between the fixed side 15 receiving piece 227 and the pivotal movement side receiving piece 230 and supports the weight of the portion pivotally moved about the iateral shafts 206 with the rear steering column -D041.

"if. /In the case of such prior-art structure shown in Figs. 16 and 17, when the rear steering column 204a is in its neutral state (a state in which the center axis of the fore steering column 2U3 anr the c:nter axis ot the rear steerinc column ir204a ,r 1 incide:l t wi th each other and the height ,if the inr w;l.-el i iln an intermediate position), th,- c~nt.r axis o the compression coil spring 22o lies ;n aI st: iight line from its fore end to its rear end. In other word;, tt.

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-11center of the bent-up piece 231 and the aoit- r of the concave hole 232 lie on a straiaht line, indi th- co-ntor axis of the fore end portion of the comp Sion coil spring 226 and the center axis of the rear end portion of this compression coil spring 226 coincide with each other. When from such a neutral state, the rear steering column 204a is pivotally moved in a counterclockwise direction to elevate the height position of the steering wheel, the compression coil spring 226 o S 10 becomes curved in a direction for the underside thereof to become arcuately convex as shown in Fig. 18 of the accompanying drawings. In contrast, when the rear steering column 204a is pivotally moved in a clockwise direction to lower the height position of the steering wheel, the compression coil sprinq 226 bromes curved in a direction for the upper side thereof to beco'iie arcuately convex as shown in Fig P) of he accompanying dra;insgs A structure u-ini t:lo compression coil spring 226 which becomecs triiht in the neutral position in this manner to support the weight of the rear steering column 20-14 dcribed for example, in Japanese Patent A' i t in ii-Op 1 en No. 1-1274 In t-h.e ttrucIuru shown in V 1 t he structure ot a retra1ine me Chi v r- Ji t r(vi iotw'p.

the portion fixed to the rear teerilrn i'n:un 2ila 1 nd the portion fixed to the fore steerini ilm nn -12somewhat differs from the structur(. shown in Fi i to 8. That is, inri the structure shownii in Fics Io to 19, a first engagement member 209a having first engagement teeth 210a which are straight in the form of a rack formed on the underside thereof is fixed to the underside of a support bracket 205 fixei. o the rear end portion of the fore steering column 203. Also, the rear end portion of a second engagement member 212a having second engagement teeth 213a which also are 10 straight in the form of a rack formed on the upper &4 Surface of the fore end portion thereof is pivotally supported on the underside of the fore end portion of the rear steering column 204a. The first and second *0 engagement teeth 210a and 213a are engageable with each 15 other by a tilt lever, not shown. Such a restraining mechanism is not an essential portion of the present *000*0 invention, but its action itself is simrrilir to thdt of the structure shoown in Figs. 5 to ii. Fur t her, )Lmore specific structure of the restraining mechanii 1sm shown 0 in Figs. 16 to 19 is described in detail in Japanese Patent Application No. 6-123907 and thor-cfore need not be described in letail herein.

In the cx-- of the prior-art tilt t1pe ti-ring apparatus constructed and used as us:ribel dhLv. t e compression coil spring 226 produces ununuiil :conrid witi the pivotal movement of the rear st-riir ii C()IIcl mm 2041.

That is whIr t le direc tio ns of force: tppl ie frem t h -13opposite ends of the compression coil spring 226 are continuously changed while a force in a compressing direction is applied to the compression coil spring 226, the compression coil spring 226 vibrates at the moment when the neatral position is cleared. For example, when the rear steering column 204a is changed from the state shown in Fig. 18 to the state shown in Fig. 19 via the state shown in Fig. 16, the direction of curve of the compression coil spring 226 suddenly 4 *if 10 changes at the moment when the neutral position shown Soo.

e.g. in Fig. 16 is passed, and this compression coil spring 226 vibrates. On the basis of this vibration, the compression coil spring 226 produces unusual sound which gives an unpleasant feeling to a crew such as a 15 driver. Of course, such unusual sound is als roduced when the rear steering column is changed from the state shown in Fig. 19 to the state shown in Fig. 18 via the state shown in Fig. 16.

In order to prevent the production of such unpleasant unusual sound, a member having a damming property such as a rubber tube has heretofore been put over the compression coil spring 226 or the end surt'fa of the compression coil sp-inq 22, aind the inner peri :ieral side: of th coil porticn have here.t:of orte been guided by a member made of s:.;:het i re~;in.

However, such prior-art structure requires iiscret.i parts for preventing the productic:. of urnuull s:ound, -14which is the cause of the increased manufacturing co;st::, of the tilt type steering apparatus.

(iv) In the case of the prior-art tilt type steering apparatus shown in Figs. 5 to 8, it is difficult to make a reduction in costs and an improved feeling of operation compatible. That is, to prevent the backlash of the steering wheel with the height position of the steering wheel fixed, it is necessary for the fixed side meshing teeth 10 and the 10 displacement side meshing teeth 13 to mesh with each Other reliably without any backlash (deeply). For this purpose, it is necessary that the directions of the meshing teeth 10 and 13 be made coincident with each other. If the directions of these meshing teeth 10 and 15 13 deviate from each other, the meshing engagement between these meshing teeth 10 and 13 will become

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unreliable (the meshing teeth 10 and 13 will mesh with each other only shallowly) even if the other end portion of the engagement member 12 is brought close to the restraining member 9, and this is liable to become the cause of the backlash of the steering wheel. Also, a feeling of moderation will become null as to the pivotal movement of the tilt and t:hi: ht the cause of a feeling of physical ,isorder aiven t.the operator.

On the other hand, a plurality of members (in th case of the structure of Figs. 6 to 8, the rear steering column 4, the lateral shafts 6, 6 the support bracket 5 and the lateral shaft 11) are present between the restraining member 9 provided with the fixed side meshing teeth and the engagement member 12 provided with the displacement side meshing teeth 13.

Therefore, the directions of the meshing teeth 10 and 13 are liable to deviate from each other on the basis of the shapes and dimensional errors of these members 4, 6, 5 and 11.

In other words, to make the directions of the meshing teeth 10 and 13 coincident with each other, it is necessary to regulate the shapes and dimensional accuracy of these members 4, 6, 5 and 11 considerably strictly. It becomes the cause of the increased manufacturii.g costs of the members and accordingly the increased manufacturing costs of the tilt type steering apparatus to regulate the shapes and dimensional accuracy of the plurality of members 4, 6, 5 and 11 thus strictly, and this is not preferable.

Summary of the Invention It is the object of the present invention to overcome or substantially ameliorate at least some of the above disadvantages.

There is disclosed herein a tilt type steering apparatus provided with a fore steering column, a fore steering shaft supported inside said fore steering column for rotation only, V. a support bracket fixed to a vehicle body with the rear end portion of said fore steering column supported on and fixed to said support bracket, a first lateral shaft provided on a portion fixed to said support bracket, a rear steering column having its fore end pivotally •i 20 supported by said first lateral shaft, a rear steering shaft supported inside said rear S steering column for rotation only, a universal joint connecting the fore end portion of said rear steering shaft and the rear end portion of said fore steering shaft together, a second n lateral shaft provided on a portion fixed to one member of said rear steering column and said support bracket, an engagement member having one end thereof pivotally supported on said second lateral shaft and having the other end portion thereof forned with rack-like displacement side meshing teeth, a restraining member having rack-like fixed side S meshing teeth provided on a portion fixed to the other member of said rear steering column and said support bracket and opposed to said displacement side meshing teeth, and releasably engageable with said displacement side meshing teeth, and a tilt lever for bringing said displacement side meshing teeth and said fixed side meshing teeth into and out of engagement with each other with the pivotal movement thereof, wherein said restraining member is supported on and fixed to said other member for free adjustment of an angle formed by a line along a tooth trace of the fixed side meshing teeth with a line along a tooth trace of the displacement side meshing teeth.

Brief Description of the Drawings A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings, wherein: IN: \i.I A31101220T[MX 16 Fig. 1 is a half transverse cross-sectional view showing a first embodiment of the present invention; Fig. 2 is a cross-sectional view taken along the line II-II of Fig. 1 with some portions omitted; Fig. 3 is an enlarged cross-sectional view taken along the line III-III of Fig. 1; Fig. 4 is a view similar to Fig. 3 but showing a second embodiment of the present invention; Fig. 5 is a side view showing a first example of the known tilt type steering apparatus; Fig. 6 is an enlarged cross-sectional view of the portion VI of Fig. Fig. 7 is a cross-sectional view taken along the line VII-VII of Fig. 6; Fig. 8 is a view, partly in cross-section, taken along the arrow VIII of Fig. 6; Fig. 9 is a view similar to Fig. 7 but showing a second example of the tilt type steering apparatus of the prior-art structure; oees (N:\LI.LLO I 226:TCW -17- Fig. 10 is a half transverse cross-sectional view showing another embodiment of the present invention; Fig. 11 is a cross-sectional view taken along the line XI XI of Fig. 10 with some portions omitted; Fig. 12 is a longitudinal cross-sectional view showing the essential portions of still another embodiment of the present invention; Fig. 13 is a view of the Fig. 12 embodiment as it is seen in the axial direction rightwardly from above 10 it; Fig. 14 is a view similar to Fig. 12 but showing a state in which a rear steering column has been 0* pivotally displaced to its uppermost position; Fig. 15 is a view similar to Fig. 12 but showing a 15 state in which the rear steering column has been pivotally displaced to its lowermost position; Fig. 16 is a longitudinal cross-sectional side view showing the essential portions of the prior-art structure incorporating a compression coil spring therein; Fig. 17 is a view of the Fig. 16 structure as it is seen in the axial direction riahtwardly from above it; Fig. 18 is a view similar to Fig. 16( but showinq state in which a rear steering column has been pivotally displaced to its uppermost position; Fig. 19 is a view similar to Fig. 16 but showinq a -18s-ate in which the rear steering cclumn hoen pivotally displaced to its lowermost pos: .ion; Fig. 20 is a longitudinal cross-sectional ;id' view showing the essential portions of yet still another embodiment of the present invention; and Fig. 21 is a view of the Fig. 20 embodiment as it is seen from below it.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 10 Figs. 1 to 3 show a first embodiment of the present invention. On a support bracket 5b fixedly supported on a vehicle body side, a pair of right and left vertical plate portions 33 and 33 are provided at an interval in parallelism to each other. In the case 15 of the shown embodiment, this support bracket comprises a holding portion 34 formed into a U-shape by bending a sufficiently rigid steel plate, dnd a mounting plate portion 35 welded ani fixeL to the up:per end edge of the holding portion 34. duri.n the 20 assembly of a tilt type steering apparatus, the mounting plate portion 35 is supported on the vehicle body by volts, not shown. Also, the fore- l porti (the left end portion as viewed in Fig. 1 of steering column 4b constituting the rear p-rti;: steering column 2 is pivotally held inside_ the :un 1 i plate portion 34 by a pair of right and le:t pivot in:: 6b and 6b disposed concentrically with each:. ctL:.

-19- That is, the pair of pivot pins 6b and 6b are extended between the right and left sides of the fcre end portion of the rear steering column 4b and the pair of vertical plate portions 33, 33.

The rear steering column 4b is comprised of a pivotally movable bracket 36 made by die-casting an aluminum alloy, and a column tube 37 having its fore end portion fitted and fixed to the pivotally movable bracket 36. Inside such a rear steering column 4b, a rear steering shaft 38 is supported for rotation only by a pair of fore and rear bearings 39a and 39b. The fore end portion of the rear steering shaft 38 is Sconnected to the rear end portion (the right end portion as viewed in Fig. 1) of a fore steering shaft 15 41 through a universal joint 40. The center of displacement of the universal joint 40 lies on the extension of the center line of the pair of pivot pins 6b and 6b.

In order to pivotally support the fore end portion 20 of the rear steering column 4b thus constructed and supporting the rear steering shaft 38, by the pair of pivot pins 6b and 6b, a pair of small-diametered circular holes 42 and 42 concentric with e::ih other aire formed in the right and left sides of te :r:re end portion of the rear steering column 4b. That is, thick portions 43 and 43 are formed on the richit ind lett: sides of the fore end portion if the pivotally movthle bracket 36 and the small-diamftered ,irc liri holes:: .1 and 42 are formed concentri-al ly *'it:h o.i -)th t he thick portions 43 and 43. These small-dicmetered circular holes 42 and 42 are formed so as to extent through the thick portions 43 and 43, and the outer end portions of the small-diametered circular holes 42 and 42 open into the right and left outer sides of the fore end portion of the pivotally movable bracket 36.

On the other hand, reinforcing plates 30a and 10 are welded and fixed to the right and left outer sides e of the rear end portions of the vertical plate portions 33 and 33. A pair of large-diametered circular holes 44 and 44 are formed through the inner sides of the vertical plate portions 33 and 33 to .ter sides of 15 the reinforcing plates 30a and 30a. C grooves extending through the reinforcing plates 30a and Sfrom the upper surfaces to the lower surfaces thereof are formed in the inner sides of portions of the reinforcing plates 30a and 30a. The openings in the S 20 inner sides of the concave grooves 45 are closed by the vertical plate portions 33 and 33 zo thereby form restraining holes 48 vertically ex-:endinu through thec reinforcing plates 30a and 3i0a. T..e rostrIininq holes 48 are formed in twis-ed positional relationship with the large-diametered circular holes 44 iand 44, ind the vertically intermediate portions- thereof open into the inner peripheral surfaces of t:.e iIntermoeliato -21 portions of the large-diametered circular hiole:; 411 4! 44.

The pair of pivot pins 6b and 6b have their smalldiametered portions 28a, 28a and large-diametered portions 27a, 27a connected together by stepped portions 29a and 29a. Such pivot pins 6b and 6b each are made as a unit, for example, by precutting stainless steel, an aluminum alloy or the like, diecasting an aluminum alloy, or the injection molding of synthetic resin. With the large-diametered portions 27a and 27a forced into the large-diametered circular holes 44 and 44, the small-diametered portions 28a and 28a are inserted in the small-diametered circular holes 42 and 42 for relative rotation. Spacers 47 and 47 15 made of a slippery material such as synthetic resin and formed into a circular ring-like shape are sandwiched between the stepped portions 2' i. ,29 1 unc the thick portions 43, 43. These spacers 4, and 47 serve to mitigate friction acting between the stepped portions 20 29a, 29a which are not displaced even during the tilting operation and the outer sides of the thick portions 43, 43 which are displaced during the tiltinoperation.

Further, restraining concave grooves 4o, I4t airo formed in the outer peripheral surfaces of thti intermediate portions of the large-diametered portion: 27a, 27a over the entire circumference threof.

-22- These restrainiri: concave cr:',ves 4- 4 li n t.h stopped portions 29a, 29a with th< inter: ed!i -itc portions of the restraining holes 4 which cpen into the inner peripheral surfaces of the large-diametered circular holes 44, 44 with the stepped portions 29a, 29a rammed against the outer sides of the thick portions 43, 43 through the spacers 47, 47. Spring pins 49, 49 are pushed in such restraining holes 48 from the upper end or:nings in the restraining holes 10 48. These sp.:ing pins 49, 49 are formed with curved portions 50 engageable with the restraining concave grooves 46, 46 in the intermediate portions thereof, and impart a resilient force in a direction away from the curved portions 50 to the upper and lower end 15 portions of the restraining concave grooves. Also, bent portions 51 longer than the width of the restraining holes 48 are forme, in the upper end portions of the spring pins 49, 49 to thereby regulate the amount of entry of the spring pins 49, 49 into the restraining holes 48. With such spring pins 49, 49 pushed in the restraining holes 48, the curved portions enter a part of the restraining concave grooves 46, 46 and at tho sam< time, thO upper :nd lower nd p)ortions of the :ring pins 49 resili::intly re: the inner sides of the restraining holes As a result, the curved portions 50 will not cnoe off the restraining concave grooven l6, 46 while rosi in n -23the restraining concave grooves 46.

In the case of the illustrated embodiment, the base end portion of a tilt lever 7a is pivotally supported on the outer end portions of the largediametered portions 27a, 27a constituting the pivot pins 6b, 6b which protrude from the outer sides of the reinforcing plates 30a, 30a. By this tilt lever 7a being operated, it is made possible to position and fix i the rear steering column 4b relative to the support 10 bracket 5b and release the fixing thereof. However, a tilt mechanism comprising such a tilt lever 7a has no direct relation to the present invention and use can be made of conventional various mechanisms and therefore, such tilt mechanism need not be shown and described in

IV,

S 15 detail.

In the case of the pivotally movable support **In apparatus for the tilt type steering apparatus of the present invention constructed as described above, the assembling work is easy and the higher efficiency of the work of manufacturing the tilt type steering apparatus can be achieved. That is, the work of supporting the rear steering column 4b on the support bracket 5b is acc:mplished by inserting the' smalldiametered portions 28a, 28a of the pivot pins 6b, rb into the small-diametered circular holes 42, 42 in the pivotally movable bracket 36, forcing the largediametered portions 27a, 27a into the large-diametc r~i -24circular hole-; 44, 44 in the support bracket 5b andc further, inserting the spring pin,-' 4'I into the restraining holes 48. This work ca;i be done eaily without requiring particularly cumbersome work such as torque regulation or the mounting and dismounting of a receiving mold and any special tool.

Fig. 4 shows a second embodiment of the present invention. In the case of this embodiment, a restraining hole 48a is a circular hole and a pin 52 is 1. 0 forced into this restraining hole 48a from the upper end opening side thereof. The lower end portion of 0** this pin 52 is brought into a portion of a restraining concave groove 46 formed in the large-diametered portion 27a of the pivot pin 6b. As the pin 52, use 15 can be made of a pillar-like needle roller pin, besides a partly cut-away cylindrical spring pin. Again in the case of the present embodiment, the work of assembling 9b the pivotally movable support apparatus for the tilt.

type steering apparatus is easy and the higher 20 efficiency of the work of manufacturing the tilt type steering apparatus can be achieved.

The pivotally movable support apparatus for the tilt type steering appAratusa of t-he pree!nt inv~*nt:i on is constructed and acts as described ebove aid therefore, by the heightened efficiency of the work ot manufacturing the tilt type steering apparatus, it cin contribute to reduction in the costa of an automobile provided with th i it: ty )ype teering apparatus.

Figs. 10 andi 11 show anther embodiment or( thc present invention. On a support bracket 105a supported on and fixed to the vehicle body side, a pair of right and left vertical plate portions 127 and 127 are provided at an interval in parallelism to each other.

In the case of the illustrated embodiment, the support bracket 105a comprises a U-shaped holding portion 128 formed by bending a sufficiently rigid steel plate, and a mounting plate portion 129 welded and fixed to the 'upper end edge of the holding portion 128. During the assembly of the tilt type steering apparatus, the mounting plate portion 129 is supported on the vehicle body by bolts, not shown. Inside the holding portion 15 128, the fore end portion (the left end portion as viewed in Fig. 10) of a rear steering column 104a constituting the rear portion of a steering column 102 is pivotably held by a pair of right and left pivot pins 106a and 106a disposed concentrically with each 20 other. That is, this pair of pivot pins 106a and 106a are extended between the right and left sides of the fore end portion of the rear steering column 104n and the pair of vertical plate portions 17.

The rear steerinq column 10Li.1 c:m::2tri:;> Lit io 2i pivotally movable bracket 1ii' mad e by di2e- :::t:inj an aluminum alloy, and a column tube 131 hi'vi:i it: fore end portion fitted and fixed to the piv'tl ly ::;ovable 1)rI C, 1, t: 1. in -i s uc ;eI 1 r- 'r I uiui r L r a tE' n f L t132 is (Ip t ts L i It xi.

only by a pair of fore and rear Laairincis 1 31 -iand] I PI3h.

The fore end portion of the rear steering shaft 132 is connected to the rear end portion, (the right end portion as viewied in Fig. 10) of a fore steering shaft 135 through a universal joint 134. The center of displacement of the universal joint 134 lies on the extension of the center line of the pair of pivot pins 106a arid 106a.

In oroar to pivotally support the fore end poi.tion of -the rear steering column 104a constructed as described above and supporting the rear steering slhaFd: 132, by the pair of pivot pins 106a and 106a, a pair of small -diame te red circular holes 136 and 136 con-.-ntric :ilh each iatner are formed in the right ar'- I ri L sides D~jL .tno i for I f t Ian a t Li I-10, 1er 1i wl1n iUn. V at; is, :r portions, tor fned or' right andl .ef t sides of thn fnzi :2 vrtion of tie pivotally movahIa brackel- 130, and tnia small-diametered circular holes 136, 136 are fa)Tmod in the res.-pective tri ck portions 137, 1:37 cn~ ri. .i ihec ti t arme-d thr,-Avih thr'" thick part ten I 1 7 nci tl, o ute r cni po L t .c iCOP o f t ho t. I f rc'ri 1ir holes 136, 1i3-, opoa into the riuh-t .'d1 ol t he f o r er. ts i- 1 r t.<n i o f t he iveit,, 7' Ii I r t -27- 130.

On the other hand, reinforcin: plates 138, 138 are welded and fixed to the right and left sides of the rear end portion of the vertical plate porti-ns 127, 127. A pair of large-diametered circular holes 139, 139 are formed through the inner sides of the vertical plate portions 127, 127 to the outer sides of the reinforcing plates 138, 138.

Also, the pair of pivot pins i06a, 106a comprise 10 small-diametered portions 140, 140 and large-diametered 'portions 141, 141 connected together by stepped portions 142, 142. Such pivot pins 106a, 106a are integrally made, for example, by pre-cutting stainless steel, an aluminum alloy or the like, die-casting an 15 aluminum alloy or injection molding of synthetic resin.

With the large-diametered portions 141, 141 forced into the large-diametered circular holes 139, 139, the small-diametered pcrtions 140, 140 are inserted in the small-diametered circular holes 136, 136 for relative 20 rotation. Spacers 143, 143 formed into a circular ring-like shape by a slippery material such as synthetic resin are held between stepped portions 142, 142 and the outer sides of th-: thick portions 137, 137. These spacers 143, 143 serve to mitiq'ite friL:tion acting between the stepped portion:: 14k, 14. which are not displaced even during the tilt:n ope.rtion ii the outer sides of the thick portions 137, 3I which rrn -28displaced during the tiltiing 'per -tion.

Further, the outer end porti;:is of the ,Iil()ediametered portions 141, 141 are protruded from the outer sides of the reinforcing plates 138, 138. The amount of protrusion of the large-diametered portions 141, 141 from the outer sides of the reinforcing plates 138, 138 is equal to or greater than the thickness T 44 of pivotally movable arm portions 144, 144 constituting a tilt lever 107a which will be described below (L 41 The tilt lever 107a for accomplishing the positioning and fixing of the rear steering column 104a "relative to the support bracket 105a and the release thereof is formed by bending a sufficiently rigid 15 metallic plate such as a steel plate or a stainless steel plate. This tilt lever 107a is provided with a pair of pivotally movable arm portions 144, 144 parallel to each other, a pair of circular holes 145, 145 formed in the tip end portions of these pivotally 20 movable arm portions 144, 144, and a connecting plate portion 146 connecting the base end portions of the pivotally movable arm portions 144, 144 together.

Such a tilt lever 107a is pi'v.-tally supportedl on the support bracket 105a by the circular holes 145, 14K being fitted onto the outer end portions of the liarediametered portions 141, 141 const itutinrj th- pivot pins 106a, 106a. This fitting work is carried (Iut by -29any one of the following methods and With the small-diametered circular -o, 136, the large-diametered circular holes 139, 139 and the circular holes 145, 145 disposed concentrically with one another, the pivot pins 106a, 106a are inserted from outside the circular holes 145, 145 into the holes 136, 136. The large-diametered portions 141, 141 of the pivot pins 106a, 106a are then forced into the large-diametered circular holes 139, 139.

The large-diametered portions 141, 141 of the pivot pins 106a, 106a are forced into the largediametered circular holes 139, 139 in advance, and with the spacing between the tip end portions of the pair of pivotally movable arm portions 144, 144 resiliently 15 widened, the circular holes 145, 145 are fitted onto the outer end portions of the large-diametered portions 141, 141.

By which of the foregoing methods the fitting :work should be done may be suitably selected, but by 20 whichever method the fitting work has been done, the outer end portions of the large-diametered portions 141, 141 protrude by 68, (2 0) from the outer sides the pivotally movable arm portions 144, 144.

Therefore, the engagement between the outer portions of the large-diametered portions 141, 141 the circular holes 145, 145 takes place reliably, an irrespective of the pivotal movement of the 'ilt: 107a, this engagement will not be inadvertently released. Also,-the above-mentioned amount of protrusion 641 will suffice if it is of such a degree that the engagement is not inadvertently released, and need not be so great and thus, the maximum width of the mounted portion of the tilt lever 107a does not increase.

The restraining mechanism engaged and disengaged by the tilt lever 107a as described above has not direct relation to the present invention, and use can be made of various conventional mechanisms, including the mechanism shown in Figs. 6 to 8, and therefore the restraining mechanism need not be shown and described in detail.

In the case of the tilt type steering apparatus of the present invention constructed as described above, the assembling work is easy and the high efficiency of

U

the work of manufacturing the tilt type steering apparatus can be achieved. That is, the work of 20 pivotally supporting the tilt lever 107a on the support bracket 105a can be done easily without requiring any particularly cumbersome work such as torque regulation or the mounting and dismounting of a receivii n mold or any special tool.

The tilt type steering apparatus of the present invention, which is constructed and acts as described above, can contribute to a reduction in the costs of an -31 ou mobile provided with the tilt type[ steerini apparatus, by the heightening of the efficiency of the work of manufacturing the tilt type steering apparatus.

Also, the maximum width dimension is made small and the installation of the apparatus in a narrow space becomes possible and therefore, design becomes easy.

Figs. 12 to 15 show still another embodiment of the present invention. The feature of this embodiment resides in the structure of a portion in which to S 10 suppo::t the weight of a rear steering column 204a, a compression coil spring 226 is disposed between the rear side (the right side as viewed in Figs. 12, 14 and 15) of a fixed side receiving piece 227 secured to a support bracket 205 and the fore side (the left side as 15 viewed in Figs. 12, 14 and 15) of a pivotally movable side receiving piece 230 secured to a pivotally movable bracket 229. In the other points, the construction and action of the present embodiment are similar to those .of the prior art shown in Figs. 5 to 8 or Figs. 16 to S 20 19 and therefore, overlapping description will be omitted or simplified and chiefly the characteristic portions of the present embodiment will hereinafter be described.

A bent-up piece 231 is bent up on the rear side of the fixed side receiving piece 227 perpendicularly to this rear side, and the fore end portion (the left lower end portion as viewed in Figs. 12, 14 and 15) of -32the compression coil spring 226 is titted on the bontup piece 231. Also, a circular concave hole 232 is formed in the fore side of the pivotally movable side receiving piece 230 in a direction perpendicular to this fore side, and the rear end portion (the right upper end portion as viewed in Figs. 12, 14 and 15) of the compression coil spring 226 is fitted in the concave hole 232. In the case of the tilt type steering apparatus of the present embodiment, unlike the aforedescribed prior-art structure, the center axis a of the bent-up piece 231 and the center axis P of the concave hole 232 do not coincide with each other. In the case of the illustrated embodiment, when as shown in Fig. 12, the rear steering column 204a is brought into its neutral position, the center axes a and P become parallel to each other, but the center axis p of the concave hole 232 exists in a portion nearer to a steering shaft 201 than the center axis a of the bentup piece 231.

20 Accordingly, even when the rear steering column 204a is in its neutral position, the compression coil spring 226 does not become straight. In the case of the illustrated embodiment, more specifically, the underside becomes convexly curved except the vicinity of the rear end portion fittel in the concave hole 232.

Even if in order to elevate a steering wheel from this state, the rear steering column 204a is c -33counter-clockwisely pivotally moved to a position shown in Fig. 14, the compression coil sprirn 22u will have its underside kept convexly curved. With the rear steering column 204a thus pivotally moved to the position shown in Fig. 14 to elevate the steering wheel, the rear end portion of the compression coil spring 226 becomes substantially straight. Further, even if in order to lower the steering wheel from the neutral position, the rear steering column 204a is clockwisely pivotally moved to a position shown in Fig.

15, the compression coil spring 226 will have its underside kept convexly curved except the vicinity of S.2 the rear end portion fitted in the concave hole 232.

Thus, in the tilt type steering apparatus of the 15 present embodiment, the entire compression coil spring 226 does not momentarily change its direction of curve.

Therefore, even if a member for the prevention of vibration is not particularly provided, it will never happen that the compression coil spring 226 produces 20 unusual sound which will give an unpleasant feeling to the crew. In the illustrated embodiment, the rear end portion of the compression coil spring 226 is positioned near the steering shaft 201, as compared with the fore end portion thereof, but alternatively the directions of displacement of these end portion: may be converse to those in the case shown.

The present embodiment is constructed and acts ,s -34described above and therefore, there c:an be inexpensively obtained a structure which doe. neot: ive an unpleasant feeling to the crew.

Figs. 20 and 21 show still another embodiment of the present invention. A fore steering shaft 322 is supported for rotation only inside a fore steering column 303. The rear end portion (the right end portion as viewed in Figs. 20 and 21) of the fore steering column 303 is supported on and fixed to a support bracket 305 made as by press-molding a metallic plate This support bracket 305 is fixed to a vehicle body under a dashboard 308 (see Fig. The fore end of a rear steering column 304 is pivotally supported on the rear end portion of the support bracket 305 by 15 lateral shafts 306, 306 which are first lateral shafts.

For this purpose, circular holes are formed in the i right and left sides of the fore end portion (the leftend portion as viewed in Figs. 20 and 21) of the rear steering column 304 made as by die-casting an aluminum 20 alloy, and the inner halves of the lateral shafts 306, 306 are inserted in the circular holes. Accordingly, the rear steering column 304 is supported for pivotal movement about the lateral shafts 30, 306 relative to the support bracket 305.

Inside the rear steering -olu:mn 304 thus: supported, a rear steering shaft 323 is supported for rotation only by a pair of fore and rear deep groove type ball bearinc:: 324. The fore end portion (the left end portion as viewed in Fig. 20) of the rear steerintj snaft 323 and the rear end portion (the right end portion as viewed in Fig. 20) of the fore steering shaft 322 are connected together by a universal joint 325. In the case of the illustrated embodiment, the center of displacement of this universal joint 325 is disposed on the extension of the pair of lateral shafts 306 and 306. Accordingly, even when the rear steering 10 column 304 is pivotally moved about the lateral shafts 306, 306, the transmission of rotational force between 4* the fore steering shaft 322 and the rear steering shaft i. 323 is effected smoothly.

Also, a second lateral shaft 326 is provided under 15 the fore end portion of the rear steering column 304, and the rear end portion (the right end portion as 44 viewed in Figs. 20 and 21) of an engagement member 312 is pivotally supported on the second lateral shaft 326.

Rack-like (flat gear-like) displacement side meshing S 20 teeth 313 are formed on the upper surface of the fore end portion (the left end portion as viewed in Figs. and 21) of the engagement member 312. On the other hand, a restraining member 309 is fixed to thit port i n of the underside of the support bracket 30 which i; opposed to the displacement side meshing teeth 313 in(i rack-like fixed side meshing teeth 310 are formed on the underside of the restraining member 309.

-36 The displacement side meshing teeth :31i and th-l fixed side meshing teeth 310 are releasably engageib.l with each other on the basis of the pivotal movement of a tilt lever 307. This tilt lever 307 is pivotable about the lateral shaft 306 and is pivotally supported on the support bracket 305. A forwardly extending arm portion 327 is provided on a portion of the tilt lever 307, and a substantially lozenge-shaped through-hole 328 is formed in the fore end portion of this arm I 10 portion 327. A pin 329 projectedly provided on a side of the forward end portion of the engagement member 312 is loosely fit-ed in the through-hole 328.

Accordingly, in a state in which the tilt lever 307 has been pivotally moved clockwisely as viewed in Fig. 15 and the lower edge of the through-hole 328 bears against the underside of the pin 329, the fore end portion of the engagement member 312 is pushed upwardly and the displacement side meshing teeth 313 come into meshing engage.ent with the fixed side meshing teeth 310. Conversely, in a state in which the tilt lever 307 has been pivotally moved counter-clockwisely as viewed in Fig. 20 and the upper edge of the throughhole 328 bears against the upper c:urf.:: of th pin 329, the fore end portion of the en,; mnembr 12, and the engage-ment between the displacement side meshing teeth 313 and the fixed sid, meshini teetth is released.

-37- In the case of the tilt type steering appar-atu; L: the present invention, in crder to reliably brincj tl-h, displacement side meshing teeth 313 into meshinq engagement with the fixed side meshing teeth 310 with the tilt lever 307 pivotally moved clockwisely as viewed in Fig. 20, the restraining member 309 is supported on and fixed to the underside of the support bracket 305 which is the other member, for free adjustment of the angle of inclination of the fixed 10 side meshing teeth 310 with respect to the direction of tooth trace thereof. That is, a circular concave hole 330 is formed in the upper surface of the fore end S" portion (one end portion) of the restraining member 309 and a circular convex portion 331 is formed on the 15 underside of the fore end portion of the support bracket 305, and the concave hole 330 and the convex portion 331 are brought into engagement with each other. Accordingly, the fore end portion of the restraining member 309 is restrained on the support 20 bracket 305 for pivotal movement with respect to the direction of tooth trace of the fixed side meshinq teeth 310. A stud 333 is threadaly tngaqiaed with athreaded hole formed in an L-shaped keep plate portion 332 formed on the fore end edge of the, uport braicko! 305, and the upper end surface: of thi; stud 333 i: rammed against the underside of the tore end portion o: the restraining member 309 to thereby prevent thi; -38restraining member 309 fro;: flo-,ti:. up rom the underside of the support bracket A'.rs, a l(rk int 334 is threadably engaged with the stud 333 to thereby prevent the loosening of this stu- 333.

On the other hand, a nut 336 is fitted and fixed to the upper end opening portion of a circular hole 335 formed in the rear end portion of the support bracket 305. Also a through-hole 337 is formed at a location in the rear end portion (the other end portion) of the 10 restraining member 309 which is aligned with the circular hole 335. A fixing bolt 338 is inserted into the through-hole 337 from below to above the

T

restraining member 309. This fixing bolt 338 comprises a small-diametered portion 339 and a large-diametered 15 portion 340 connected together by a stepped portion 341, and an externally threaded portion threadably engaged with the nut 336 is forme' on th- tip end portion of the small-diametered :rtion ,40, and a hrad 342 for engaging a tool (for example, a hexagonal 20 wrench) is formed on the base end portion of the largediametered portion 340. The small-diametered portion 339 is loosely insertable into the throuch-hole 337, while the large-diametered portifo. 340 c.nnot pass through this throuc(h-hole i :ix th.. roar ini portion of the restrainincg Ji~ to th- support bracket 305, an externally thiread<.i portion formed n the tip end portion of the fixin( lt 33-i brouriht -39into threidable enrgagement with the nut 333. and is; fastened, and the rear end portion of the r:-;training member 309 is firmly held between the stepped portion 341 and the underside of the support bracket 305.

On the basis of the fastening of the fixing bolt 338, the restraining member 309 is supported relative to the support bracket 305 at longitudinally two locations and is immovably fixed to the underside of this support bracket 305. The mounting angle with respect to the direction of tooth trace of the fixed side meshing teeth 310 is freely adjustable within a range in which inside the through-hole 337, the smalldiametered portion 339 of the fixing bolt 338 can be displaced in the widthwise direction (the front to back S 15 direction as viewed in Fig. 20 and the vertical direction as viewed in Fig. 21) of the restraining member 309. So, to adjust the mounting angle of the restraining member 309 in order to reliably brin( tht fixed side meshing teeth 310 and the displacement side 20 meshing teeth 313 into meshing engagement with each other, the fixing bolt 338 is loosened and the fixed side meshing teeth 310 and the displacement side meshing teeth 313 are brought into engagement with eaich other with the restraining member 30'J rendered 2i pivotally movable about: the encjagement portion b, :r !i nI the fitting of t:h concive hole 330 and the convex portion 331 to each other.

40 Lt withi the fixing bolt 338 t:hu:: 1. I t fixed side mashing teeth 310 and thO LHII) I N>'Mait. ii.

meshing teeth 313 are orought into rneshbac engagementwith each other, the direction of the displacement side meshing~ teeth 313 and the direction of the fixed side meshing teeth 310 will strictly coincide with each other and these meshing teeth 310 and' will. reliably mesh with each other without any backlash. So, if with these meshing teeth 310 and 313 remainir in. meshing engagement with each other, the fixin.., bolt 338 is fastened and the rear end portion of the restraining member 309 is supported on and fixed to the support bracket 305, the restraining member 309 can be supported on and fixed to the! support bracket 305 with the fixed side meshincg teeth 310 and the displacement side meshing teeth 313 reliably meshing w-ith eac-I ~~The I a zy- iamp~to red poCr 2on 340 W u h- t ix ii h Tobolt 338 is loosely inserted in a through-ho to 343 l1ng in the longitudinal direction thereof (the right to left direction as viewed in Figs. 20 and 21 which is, formev-d in the i nteri-iicl.iatn portioen on iome membe r 312 m~ i: prot2.rudeOs Iewn;ara lx ti Kw: t M~rs iW is fixing bol t 0" Caoo t [lath tthromlh th. ii-h A:4 ;l I. Y, tw O'n 00gwivan1~t Imt'5. o. W. tW i KI downwaird p ivo tal movemen t lim~.i ted not qni v 1' tho -41engagement between the through-hole 328 and the pin 329, but also by the engagement between the throughhole 343 an3 the head 342. A resilient member such as a leaf spring may be provided between the underside of the engagement member 312 and the upper surface of the head 342, whereby a resilient force for bringing the fixed side meshing teeth 310 and the displacement side meshing teeth 313 into meshing engagement with each other can he imparted to the engagement member 3±2.

Further, between the support bracket 305 and the rear steering column 304, there is provided a support spring 344 sufficient to support the weight of the rear steering column 304 and a member such as a steering wheel supported by this rear steering column 304. In 15 the illustrated embodiment, as this support spring 344 use is made of u co. ssion spring provided between the underside portion of the support bracket 305 and the underside portion of the rear steering column 304.

However, a tension spring provided between tha upper 20 surface portion of the support bracket 305 and the upper surface portion of the rear steering column 304 may also be adapted. In any case, it is to be understood that the resilient force of the support spring 344 is limited enough to substantially support tht weight of the member supported by the rear steering column 304. This is for preventing the steering wheel from lowering with force (when the support spring is -42absent or when its resilient force is too small) or from rising with force (when the resilient force of the support spring is too great) when the meshing engagement between the displacement side meshing teeth 313 and the fixed side meshing teeth 310 is released.

When by the tilt type steering apparatus of the present embodiment constructed as described above, the height position of the steering wheel is to be adjusted in conformity with a driver's constitution or the like, S 10 the tilt lever 307 is first pivotally moved counterclockwisely as viewed in Fig. 20 against the resilient force of the tension spring 321 to thereby lower the tip end portion of the arm portion 327. On the basis of this operation, the upper edge of the through-hole 9 15 328 pushes the upper surface of the pin 329 and the engagement member 312 is pivotally moved counterclockwisely as viewed in Fig. 20 about the second 0. lateral shaft 326. With this pivotal movement, the engagement between the displacement side meshing teeth S 20 313 and the fixed side meshing teeth 310 is released.

In this state, the rear steering column 304 is pivotally moved about the lateral shafts 306, 306 to thereby adjust the height position of the steering wheel, not shoiwn, which is fixed to the rear end portion of the rear steering shaft 323. This adjusting work can be done easily by the presence of the support spring 344. Durir.g the adjusting work, however, the -43tilt lever 307 is kept pivotally moved against the resilient force of the tension spring 321. After the adjustment, the force so far imparted to the tilt lever 307 is released and this tilt lever 307 is pivotally moved clockwisely as viewed in Fig. 20 by the resilient force of the tension spring 321. As a result, the lower edge of the through-hole 328 pushes the underside of the pin 329 upwardly and pivotally moves the engagement member 312 clockwisely as viewed in Fig. 10 about the second lateral shaft 326. With this pivotal movement, the displacement side meshing teeth 313 come

V

into meshing engagement with the fixed side meshing teeth 310 on the basis of the resilient force of the support spring 344. As a result, the steering wheel is S 15 fixed at a height position after adjusted. The present invention can also be carried out in the aforedescribed •prior-art structure shown in Figs. 5 to 8.

The present invention, which is constructed and acts as described above, can inexpensively -ealize a 20 tilt type steering apparatus in which reduced costs and an improved feeling of operation are compatible and a steering wheel is free of backlash and moreover, the feeding of operation of a tilt lever is good.

Claims (2)

1. A tilt type steering apparatus provided with a fore steering column, a fore steering shaft supported inside said fore steering column for rotation only, a support bracket fixed to a vehicle body with the rear end portion of said fore steering column supported on and fixed to said support bracket, a first lateral shaft provided on a portion fixed to said support bracket, a rear steering column having its fore end pivotally supported by said first lateral shaft, a rear steering shaft supported inside said rear steering column for rotation only, a universal joint connecting the fore end portion of said rear steering shaft and the rear end portion of said fore steering shaft together, a second lo lateral shaft provided on a portion fixed to one member of said rear steering column and said support bracket, an engagement member having one end thereof pivotally supported on said second lateral shaft and having the other end portion thereof formed with rack-like displacement side meshing teeth, a restraining member having rack-like fixed side meshing teeth provided on a portion fixed to the other member of said rear steering column and said support bracket and opposed to said displacement side meshing teeth, and releasably engageable with said displacement side meshing teeth, and a tilt lever for .i bringing said displacement side meshing teeth and said fixed side meshing teeth into and out of engagement with each other with the pivotal movement thereof, wherein said restraining member is supported on and fixed to said other member for free adjustment of 20 an angle formed by a line along a tooth trace of the fixed side meshing teeth with a line along a tooth trace of the displacement side meshing teeth.

2. A tilt type steering apparatus substantially as hereinbefore described with reference to Figures 20 and 21. e Dated 29 January, 1999 NSK Ltd Patent Attorneys for the Applicant/Nominated Person SPRUSON FERGUSON [N:\LIBI.11226:T0CW Tilt Type Steering Apparatus Abstract A tilt type steering apparatus is provided with a fore steering column 303 with a fore steering shaft 322 supported inside for rotation only. A support bracket 305 is fixed to a vehicle body with the rear end portion of the fore steering column 303 supported and fixed thereto. A first lateral shaft 306 is fixed to the support bracket 305 and a rear steering column 304 has its fore end pivotally supported by the first lateral shaft 306. A rear steering shaft 323 is supported inside the rear steering column 304 for rotation only. a universal joint 325 connects the fore end portion of the rear steering shaft 323 and the rear end portion of the fore steering shaft 322 together. A second lateral shaft 326 is fixed to the rear steering column 304 or the support bracket 305. An engagement member 312 has one end pivotally supported on the second lateral shaft 326 and the other end formed with rack-like displacement side meshing teeth 313. A restraining member 309 has rack- ~like fixed side meshing teeth 310 fixed to the other of the rear steering column 304 and support bracket 305 and opposed to and releasably engageable with the displacement side meshing teeth 313. A tilt lever 307 brings the meshing teeth 313, 310 into and out of engagement with pivotal movement thereof. The restraining member 309 is supported on and fixed to the rear steering column 304 or support bracket 305 for free adjustment of the angle of inclination thereof with respect to the direction of tooth trace of the fixed side 2 *me e 20 meshing teeth 310. e [N:\LIELJL01226:GJG