GB1599388A

GB1599388A - Hand tool for driving rotary bits

Info

Publication number: GB1599388A
Application number: GB25970/78A
Authority: GB
Original assignee: Stanley Werke GmbH
Current assignee: Stanley Werke GmbH
Priority date: 1977-06-11
Filing date: 1978-05-31
Publication date: 1981-09-30
Also published as: DK230178A; SE7805881L; AT354220B; BE867812A; NO782030L; DE2726500A1; DE2726500B2; DE2726500C3; ATA370378A; NL7806191A

Description

(54) HAND TOOL FOR DRIVING ROTARY BITS (71) We, STANLEY-WERKE GMBH, of Langenberger Strasse 32, 5620 Velbert 1, Federal Republic of Germany, a Joint-Stock Company organised under the laws of the Federal Republic of Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be par ticularly described in and by the following statement:: The invention relates to a hand tool for driving rotary bits, comprising a tool housing, a tool chuck carried by the housing, means for attaching an operating handle to the housing to effect rotation of the latter, and a drive mechanism of ratchet form contained within the housing and for drivably connecting the tool chuck to the housing, the driving mechanism comprising an axially secured ratchet bolt and two catch parts controllable from the housing exterior, which catch parts are accommodated in a bearing recess in the tool housing open towards the peripheral face of said housing and are braceable in a transverse direction between the ratchet bolt and bracing regions of the bearing recess.

Hand tools of the category initially described are known in practice, e.g., as tool holders for tap drills. Such a tool has a housing made of pressure-cast metal which at one end receives an operating handle in the form of a rod-shaped section oriented transversely to the axis of the tool housing. A tool chuck to accommodate the bits is provided at the opposite end of the housing. A drive mechanism of ratchet form is provided in the tool housing, wherein a ratchet bolt constructed as a pinion on portions of its length co-operates with two catch parts provided within a bearing recess open towards the peripheral face of the tool housing.

Said catch parts are controllable by a slide operable from the housing exterior and engaging through a sleeve enclosing the bearing recess in such a way that, depending upon the control position, said catch parts in co-operation with the ratchet bolt cause a rotary entrainment of the ratchet bolt either in the one or in the other direction of rotation and a freewheel action in the respective counterdirection. A complete locking of the ratchet bolt in each direction of rotation with elimination of the freewheel action is also possible.

During work with such a tool, the torque exerted upon the tool from the outside is transmitted by the bracing flanks of the bearing recess in the tool to the catch parts and from there through the ratchet bolt to the tool chuck.

Due to the fact that the tool housing is produced from a pressure casting with a relatively soft material structure, whereas the catch parts are constituted of a comparatively harder material, an acute danger of wear exists in the region of the bracing flanks on the tool housing from the very first time of use, which has the effect that the lateral flanks of the catch parts confronting the bracing flanks on the tool housing bite into said bracing flanks on the tool housing. This then leads inevitably to disturb ances in the function of the tool in as much as, due to inevitable play in movement, a correct rotary entrainment of the ratchet bolt is no longer possible.

In recognition of these deficiencies, it is now the aim of the invention, whilst eliminating the disadvantages previously known, firstly to improve the functional reliability of the tool and secondly to prolong its useful life, in the case of a particular tool configuration.

According to the invention, in a hand tool for driving rotary bits as above described, at least one armour section made of a material harder than that of the tool housing is provided within the latter to co-operate with the respective catch part at each bracing region of the bearing recess.

By virtue of the practical realisation of the invention it has been possible to conform the bracing regions on the tool housing for the catch parts in such a way that they exhibit a previously nonexistent stability in use. They are thus capable of withstanding the constant loads which occur within the context of the transmission of torque. It is extremely advantageous that this stabilisation of the bracing regions on the tool housing can be realised whilst retaining the previous tool housing construction. The hitherto unavoidable biting of the catch parts into the bracing regions on the tool housing, which were due to wear, has thus been efficaciously eliminated. Furthermore, the armour sections create absolutely smooth bracing regions favourable for abutment, against which snug bracing of the catch parts is possible.

It is now possible in practice, either to provide such armour sections with the bracing regions on the tool housing as separate components, as described with reference to a preferred embodiment, or else to construct said bracing regions themselves as harder and hence reinforced zones of the housing. In the case of reinforced zonal armour sections, the latter could be both worked into the bracing regions and conformed so that they themselves constitute bracing flanks. In all cases stable bracing regions are formed on the tool housing against which an extremely wear-free abutment of the catch parts is possible.

In a particularly preferred embodiment, the armour sections each have dimensions at least sufficiently great to co-operate with the whole of the braced surface of the corresponding catch part. Thus, the armour sections may be constituted by components which grip the tool housing to cover the bracing regions of the bearing recess. The bracing regions are preferably formed as lateral bracing flanks in the bearing recess, and the armour sections cover the full axial and transverse dimensions of said bearing flanks.

Conveniently, the armour sections may be constituted by spring steel sections. These armour sections are preferably formed as parts of a spring steel component in the form of a clip which can be sprung open to grip around the periphery of the tool housing to lock said component against movement relative to the housing, said component of clip form having portions which project radially into the bearing recess to overlap the bearing regions, the said radial portions having angled terminal regions constituting the armour sections. Such a component advantageously grips round the tool housing externally and is e.g. secured to the latter positively within a peripheral recess in the axial direction thereof. The armour sections in turn engage from the open side of the bearing recess radially into the latter and overlap whilst simultaneously bracing the bracing flanks for the catch parts.Such a component can be retained sprung open on the tool housing engaging into the bearing recess by the armour sections. Due to the spring elasticity of such a component a pre-tensioning effect occurs, whilst the principal section which grips around the tool housing may also be so constructed that a peripherally clamping locking of the sleeve embracing the bearing recess region is possible.

In the context of a further development of the invention, a construction which is favourable for handling during assembly, and functionally particularly efficacious, can be consuucted so that the armour sections are not a constituent of a common spring steel component, but that said armour sections are provided on separate spring steel components of clip form each of which has a principal section adapted to embrace the tool housing on only a part of the periphery thereof, each spring steel component having a portion extending at an angle to the principal section into the bearing recess, which portion has a terminal region constituting an armour section. At an interval around the principal section from said angled portion, each component of clip form may have a fixing web which can be sprung into a fixing recess in the housing.A preferred spring steel component is in the form of a C-clip, with the said angled portion and the said fixing web pointing towards one another at the ends of the Shaped principal section. In this way each C-shaped component is secured against rotation. Because the fixing webs also are positively accommodated within a peripheral housing recess, they are also secured axially.

No special fixing means are necessary.

It is likewise advantageous in this context if the said fixing recess constitutes a groove for receiving a locking part which acts to axially secure the ratchet bolt, the fixing webs of the C-shaped components also engaging said locking part to secure the latter in position in the groove. This has the advantage that when the locking part is inserted into said radial recess the fixing webs of the spring steel components grip under the locking part in the region of the fixing recess and thus retain it in position. Particular fixing means for said locking part are then likewise not required.

Furthermore, the arrangement of armour sections on two spring steel components is also advantageous in as much as constituents thereof, such as e.g., the angled fixing webs, are efficacious both in the sense of maintaining the spring steel components themselves upon the tool housing but also in the sense of a locking of the locking part for the ratchet bolt. Complicated special components as fixing parts, both for maintaining the spring steel components and also for the locking part are thereby likewise rendered superfluous, as well as the corresponding production of fixing partial recesses.

Further features of the invention will be apparent from the description given herein below of an exemplary embodiment of the invention illustrated in the accompanying drawings, wherein: Fig. 1 shows a general view of a tool holder in elevation, Fig. 2 shows a partial plan, enlarged several times compared to Fig. 1, of the tool holder in the region of the bearing recess, with the sleeve removed, Fig. 3 shows a sectional view made along the line of section III--III of Fig. 2 and Fig. 4 shows another sectional view -made it is clear that the tool housing 11 exhibits at one point a bearing recess 19 open towards the circumference 1 lea. This bearing recess, considered in the longitudinal direction of the tool housing, is bounded at its end faces by the edges 19a oriented in the peripheral direction and laterally by the flanks 19b oriented In the longitudinal direction of the tool housing.

These flanks 19b extend only over portions in the longitudinal direction of the bearing recess 19 and merge finally into radially oriented incisions 20 of the tool housing. In the interior 21 of the tool housing 11 there is mounted rotatably a ratchet bolt 22 which is secured against axial movements by a locking part 23 which is insertable through a radial recess in the tool housing 11 and comes to lie at its end face in front of a pinion part 24 of the ratchet bolt 22.

Also within the bearing recess 19, catch parts 25 and 26 are provided which are of plateshaped configuration and engage and are locked by projection parts 25a and 26a into the incisions 20 of the tool housing. These catch parts have on a portion of their length a width which corresponds to the inside width between the flanks 19b of the bearing recess 19. In axial continuation thereto each catch part forms a driver 25b or 26b. These driver parts exhibit only such a width that it is possible to enter into the region between a pinion tooth 24 and the adjacent bracing flank 19b.

Figs. 2 and 3 illustrate a position of the catch parts 25 and 26 which causes a blocking of the ratchet bolt 22 in each direction of rotation. It is now possible by controlling the slide 17 to control either the one or the other catch part 25 or 26 so that it tilts about a plane transverse to the longitudinal axis of the tool housing so that the associated driver part 25b or 26b moves out of the region of engagement along the line of section IV-IV of Fig. 2.

The tool holder 10 illustrated in Fig. 1 in cludes a tool housing 11 which has a substan tially cylindrical general shape and exhibits a terminal region 12 of head-shaped configura tion. Adjacent to the terminal region 12 there is provided a pin-shaped operating handle 13 which penetrates the tool holder 10. The tool housing 11 is enclosed by a sleeve 14. The latter is secured on the tool housing 11 by a screw 15. The operating handle 13 penetrates both the sleeve 14 and the tool housing 11 through a transverse bore. Catch means - not shown - for locking the operating handle 13 are provided on the tool housing in this region of penetration. The sleeve 14 exhibits an axially oriented control recess 16, through which a slide 17 engages.Opposite the terminal region 12 a tool chuck 18 is provided, within which exchangeable tool bits - not shown - can be accommodated.

Further particulars can best be understood from the larger scale Figs. 2 to 4. From these illustrated in Figs. 2 and 3, i.e., admits a release of the ratchet bolt in the one or the other direction of rotation. In this manner the tool can be controlled in such a way that, e.g.

an entrainment of the ratchet bolt is obtained in the case of a clockwise rotation and a kind of freewheel in the case of anticlockwise rotation The respective torque is introduced through the operating handle 13 into the tool housing 11 and is transmitted through the flanks 19b to the drivers 25b or 26b of the catch parts 25 and 26 and finally delivered through the pinion teeth 24 to the ratchet bolt and from there to the tool chuck 18.

Now, in the exemplary embodiment, armour sections 27a which constitute the angled terminal regions of spring steel components 27 are provided in the region of the bracing flanks 19b. These spring steel components 27 which have principal sections of C shape, grip round the tool housing 11 peripherally on portions of the circumference and are housed axially securely within a peripheral recess. They also constitute, in an arrangement approximately diametrically oppo site the armour sections 27a, fixing webs 27b which are likewise constituted by angled terminal regions. These fixing webs 27b each en gage into an axially oriented fixing recess 28 of the tool housing 11. This fixing recess 28 is arranged diametrically opposite the bearing recess 19 and is e.g., constructed as a groove open towards the circumference.

The armour sections 27a extend both over the total radial height and also over the entire length of the flanks 19b. They project so far radially from the circumference into the in terior 21 of the tool housing that the drivers 25b and 26b can be braced against said armour sections by their edges adjacent to the flanks 19b. The fixing webs 27b placed opposite the armour sections 27 a, when they enter the fixing recess 28, engage behind or under the locking part 23, which engages radially into the interior of the tool housing for the purpose of axially securing the ratchet bolt.

These spring steel components may each be assembled individually onto the tool housing from the side, by e.g., hooking the armour section 27a into the bearing recess 19 and then springing these components open so that the fixing webs 27b catch into the common fixing recess 28.

In a modified embodiment, the two spring steel components 27 above-described are in corporate in a single spring steel component wherein the two principal sections of C-shape are connected together. Functionally, the single spring steel clip operates in the same manner as the two separate clips 27.

WHAT WE CLAIM IS:- 1. A hand tool for driving rotary bits, comprising a tool housing, a tool chuck carried by

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **.

it is clear that the tool housing 11 exhibits at one point a bearing recess 19 open towards the circumference 1 lea. This bearing recess, considered in the longitudinal direction of the tool housing, is bounded at its end faces by the edges 19a oriented in the peripheral direction and laterally by the flanks 19b oriented In the longitudinal direction of the tool housing.

These flanks 19b extend only over portions in the longitudinal direction of the bearing recess 19 and merge finally into radially oriented incisions 20 of the tool housing. In the interior 21 of the tool housing 11 there is mounted rotatably a ratchet bolt 22 which is secured against axial movements by a locking part 23 which is insertable through a radial recess in the tool housing 11 and comes to lie at its end face in front of a pinion part 24 of the ratchet bolt 22.

Also within the bearing recess 19, catch parts 25 and 26 are provided which are of plateshaped configuration and engage and are locked by projection parts 25a and 26a into the incisions 20 of the tool housing. These catch parts have on a portion of their length a width which corresponds to the inside width between the flanks 19b of the bearing recess 19. In axial continuation thereto each catch part forms a driver 25b or 26b. These driver parts exhibit only such a width that it is possible to enter into the region between a pinion tooth 24 and the adjacent bracing flank 19b.

Figs. 2 and 3 illustrate a position of the catch parts 25 and 26 which causes a blocking of the ratchet bolt 22 in each direction of rotation. It is now possible by controlling the slide 17 to control either the one or the other catch part 25 or 26 so that it tilts about a plane transverse to the longitudinal axis of the tool housing so that the associated driver part 25b or 26b moves out of the region of engagement along the line of section IV-IV of Fig. 2.

The tool holder 10 illustrated in Fig. 1 in cludes a tool housing 11 which has a substan tially cylindrical general shape and exhibits a terminal region 12 of head-shaped configura tion. Adjacent to the terminal region 12 there is provided a pin-shaped operating handle 13 which penetrates the tool holder 10. The tool housing 11 is enclosed by a sleeve 14. The latter is secured on the tool housing 11 by a screw 15. The operating handle 13 penetrates both the sleeve 14 and the tool housing 11 through a transverse bore. Catch means - not shown - for locking the operating handle 13 are provided on the tool housing in this region of penetration. The sleeve 14 exhibits an axially oriented control recess 16, through which a slide 17 engages.Opposite the terminal region

12 a tool chuck 18 is provided, within which exchangeable tool bits - not shown - can be accommodated.

Further particulars can best be understood from the larger scale Figs. 2 to 4. From these illustrated in Figs. 2 and 3, i.e., admits a release of the ratchet bolt in the one or the other direction of rotation. In this manner the tool can be controlled in such a way that, e.g.

an entrainment of the ratchet bolt is obtained in the case of a clockwise rotation and a kind of freewheel in the case of anticlockwise rotation The respective torque is introduced through the operating handle 13 into the tool housing

11 and is transmitted through the flanks 19b to the drivers 25b or 26b of the catch parts

25 and 26 and finally delivered through the pinion teeth 24 to the ratchet bolt and from there to the tool chuck 18.

Now, in the exemplary embodiment, armour sections 27a which constitute the angled terminal regions of spring steel components 27 are provided in the region of the bracing flanks 19b. These spring steel components 27 which have principal sections of C shape, grip round the tool housing 11 peripherally on portions of the circumference and are housed axially securely within a peripheral recess. They also constitute, in an arrangement approximately diametrically oppo site the armour sections 27a, fixing webs 27b which are likewise constituted by angled terminal regions. These fixing webs 27b each en gage into an axially oriented fixing recess 28 of the tool housing 11. This fixing recess 28 is arranged diametrically opposite the bearing recess 19 and is e.g., constructed as a groove open towards the circumference.

The armour sections 27a extend both over the total radial height and also over the entire length of the flanks 19b. They project so far radially from the circumference into the in terior 21 of the tool housing that the drivers 25b and 26b can be braced against said armour sections by their edges adjacent to the flanks 19b. The fixing webs 27b placed opposite the armour sections 27 a, when they enter the fixing recess 28, engage behind or under the locking part 23, which engages radially into the interior of the tool housing for the purpose of axially securing the ratchet bolt.

These spring steel components may each be assembled individually onto the tool housing from the side, by e.g., hooking the armour section 27a into the bearing recess 19 and then springing these components open so that the fixing webs 27b catch into the common fixing recess 28.

In a modified embodiment, the two spring steel components 27 above-described are in corporate in a single spring steel component wherein the two principal sections of C-shape are connected together. Functionally, the single spring steel clip operates in the same manner as the two separate clips 27.

WHAT WE CLAIM IS:- 1. A hand tool for driving rotary bits, comprising a tool housing, a tool chuck carried by

the housing, means for attaching an operating handle to the housing to effect rotation of the latter, and a drive mechanism of ratchet form contained within the housing and for drivably connecting the tool chuck to the housing, the driving mechanism comprising an axially secured ratchet bolt and two catch parts controllable from the housing exterior, which catch parts are accommodated in a bearing recess in the tool housing open towards the peripheral face of said housing and are braceable in a transverse direction between the ratchet bolt and bracing regions of the bearing recess, wherein at least one armour section made of a material harder than that of the tool housing is provided within the latter to co-operate with the respective catch part at each bracing region of the bearing recess.
2. A hand tool according to claim 1, wherein the armour sections each have dimensions at least sufficiently great to cooperate with the whole of the braced surface of the corresponding catch part.
3. A hand tool according to claim 1 or claim 2, wherein the armour sections are constructed as components which grip the tool housing to cover the bracing regions of the bearing recess.
4. A hand tool according to any of claims 1 to 3, wherein the bracing regions are formed as lateral bracing flanks in the bearing recess, and the armour sections cover the full axial and transverse dimensions of said bearing flanks.
5. A hand tool according to any of claims 1 to 4, wherein the armour sections are constituted by spring steel sections.
6. A hand tool according to any of claims 1 to 5, wherein the armour sections are formed as parts of a spring steel component in the form of a clip which can be sprung open to grip around the periphery of the tool housing to lock said component against movement relative to the housing, said component of clip form having portions which project radially into the bearing recess to overlap the bearing regions, the said radial portions having angled terminal regions constituting the armour sections.
7. A hand tool according to claim 6, wherein a locking part is provided in a radial incision in the tool housing axially to secure the ratchet bolt, and the component of clip form has further radially extending portions which cooperate with said incision.
8. A hand tool according to claim 5, wherein the respective armour sections are provided on separate spring steel components of clip form each of which has a principal section adapted to embrace the tool housing on only a part of the periphery thereof, each spring steel component having a portion extending at an angle to the principal section into the bearing recess, which portion has a terminal region constituting an armour section.
9. A hand tool according to claim 8, wherein, at an interval around the principal section from the said angled portion, each component of clip form has a fixing web which can be sprung into a fixing recess in the housing.
10. A hand tool according to claim 9, wherein the said fixing recess constitutes a groove for receiving a locking part which acts to axially secure the ratchet bolt, the fixing webs of the Shaped components also engaging said locking part to secure the latter in position in the groove.
11. A hand tool according to claim 9 or claim 10, wherein each spring steel component is in the form of a C-clip, with the said angled portion and the said fixing web pointing towards one another at the ends of the C-shaped principal section.
12. A hand tool according to any of claims 6 to 11, wherein the spring steel component or components are locked between opposed peripheral recesses in the tool housing.
13. A hand tool for driving a rotary bit, substantially as hereinbefore described with reference to and as shown in the accompanying drawings.