US3835715A - Hammer drill mechanism - Google Patents

Hammer drill mechanism Download PDF

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Publication number
US3835715A
US3835715A US00374565A US37456573A US3835715A US 3835715 A US3835715 A US 3835715A US 00374565 A US00374565 A US 00374565A US 37456573 A US37456573 A US 37456573A US 3835715 A US3835715 A US 3835715A
Authority
US
United States
Prior art keywords
gear case
hammer
shift
case cover
spindle
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00374565A
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English (en)
Inventor
H Howell
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Black and Decker Corp
Original Assignee
Black and Decker Manufacturing Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Black and Decker Manufacturing Co filed Critical Black and Decker Manufacturing Co
Application granted granted Critical
Publication of US3835715A publication Critical patent/US3835715A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25D—PERCUSSIVE TOOLS
    • B25D11/00—Portable percussive tools with electromotor or other motor drive
    • B25D11/06—Means for driving the impulse member
    • B25D11/10—Means for driving the impulse member comprising a cam mechanism
    • B25D11/102—Means for driving the impulse member comprising a cam mechanism the rotating axis of the cam member being coaxial with the axis of the tool
    • B25D11/106—Means for driving the impulse member comprising a cam mechanism the rotating axis of the cam member being coaxial with the axis of the tool cam member and cam follower having the same shape
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25D—PERCUSSIVE TOOLS
    • B25D2211/00—Details of portable percussive tools with electromotor or other motor drive
    • B25D2211/06—Means for driving the impulse member
    • B25D2211/062—Cam-actuated impulse-driving mechanisms
    • B25D2211/067—Cam-actuated impulse-driving mechanisms wherein the cams are involved in a progressive mutual engagement with increasing pressure of the tool to the working surface
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T74/00—Machine element or mechanism
    • Y10T74/18—Mechanical movements
    • Y10T74/18024—Rotary to reciprocating and rotary

Definitions

  • ABSTRACT [30] Forelgn Apphcanml Prom), Dam A portable electric tool is adapted for drilling or ham-- July 13, Great Bl'ltall'l mer driing operations
  • the hammer drilling mecha nism is simple, reliable, easy to adjust, and facilitates [52] US. Cl. 74/22 R, 173/109 ]OW COSt high vo1ume manufacture f the tooL Addi [51] Int. Cl.
  • the a tool includes a motor housing, a gear case mounted forwardly of the motor housing, and a gear case cover therebetween, the latter constituting an internal wall in the housing.
  • An axially-retractable spindle has a rearward portion journaled in a bearing in the gear case cover.
  • a stationary hammer member is fixed in this gear case cover, radially of the spindle bearing.
  • a movable hammer member is carried by the spindle, and is provided with notched teeth adapted for ratcheting engagement with corresponding notched teeth on the stationary hammer member during the hammer-drilling mode of operation.
  • a shift member is positioned radially of the stationary hammer member, and a thrust bearing means is provided between the shift member and the movable hammer member.
  • Means including a shift button is provided to rotate the shift member through an angle about the axis of the spindle.
  • Cooperating cam means are formed between the shift member and the gear case cover, such that rotation of the shift member causes an axial translation thereof, thereby moving the movable hammer member out of engagement with the stationary hammer member during the drilling mode of operation.
  • FIG. 1 is a side elevation of the tool, with parts broken away and sectioned to illustrate its mechanism, the latter being adjusted in the hammer-drill mode of operation;
  • FIG. 2 corresponds to a portion of FIG. 1, but illustrates the mechanism adjusted for the drilling mode of operation
  • FIG. 3 is an exploded perspective of the mechanism shown in FIGS. 1 and 2;
  • FIG. 4 is a section taken across the lines 4-4 of FIG. 2.
  • FIG. 1 there is illustrated a portable electric tool referred to in the art as a hammerdrill.
  • the tool 10 has a motor housing 11, a gear case 12, and a gear case cover 13 therebetween, the latter constituting an internal wall in the tool housing.
  • the hammer-drill has a handle 14, a switch 15 for energizing a motor in the motor housing, and a chuck 16 for receiving a suitable tool bit or other implement.
  • the motor and the tool bit have not been shown.
  • the motor is provided with an armature shaft 17 journaled in a first sleeve bearing 18 in the gear case cover.
  • a pinion 19 is formed on the armature shaft, and
  • the spindle is axially retractable and spring-loaded via Belleville springs 26a. Further, the spindle has a rearward portion 26b journaled in a second sleeve bearing 32 mounted in the gear case cover.
  • a stationary hammer member comprising a flanged bushing 33, is piloted concentrically about the bearing 32 and is fixed within the gear case cover.
  • a movable hammer member 34 is carried by the spindle forwardly of the stationary hammer member.
  • the hammer members have corresponding respective notched teeth 35 and 36, see FIGS. 3 and 4, for ratcheting engagement with respect to each other in the hammerdrilling mode of operation.
  • the operator exerts a manual forward bias on the tool implement carried by the chuck; this bias pressure causes the spindle to retract axially within the gear case for ratcheting engagement of the notched teeth on the hammer members, thus providing a hammer-drilling mode of operation.
  • a shift member constituting a washer 37 is piloted concentrically about the stationary hammer member 33, and has a radially-projecting tang 38 engaged within a transverse slot 39 formed in a shift button 40.
  • the shift button which may be of suitable molded plastic, is guided for limited alternate rotary movement within an arcuate slot 41, see FIG. 4, formed in the gear case cover between the motor housing and the gear case. Because of the connection between the tang 38 and slot 39, the shift button 40 and shift washer 37 may be rotated conjointly through an angle about the axis of the spindle.
  • a cam surface 42 is formed on the side of the shift washer (confronting the gear case cover) and engages a corresponding cam formation 43, see FIG. 3, on the gear case cover.
  • the shift button 40 has arcuately-spaced respective pockets 45a and 45b adapted to alternately receive respective lugs 46a and 46b cast integrally within the gear case cover. The cooperation therebetween limits the arcuate movement of the shift button and provides a detent-type of snap action to preclude inadvertent movement of the shift button.
  • the present invention provides a low-cost, simple, reliable mechanism for a relatively high-volume power tool, which may be conveniently adjusted by the operator for either drilling or hammer drilling.
  • the two-speed gearing provides both low-speed and high-speed operation, such that a total of four distinct modes of operation are provided.
  • a portable hammer-drill the combination of a spindle journaled in a bearing in a housing, a stationary hammer member comprising a bushing piloted concentrically about the spindle bearing, a movable hammer member carried by the spindle and having notched teeth adapted to engage corresponding notched teeth on the bushing, a shift washer piloted concentrically about the bushing, thrust bearing means between the shift washer and the movable hammer element, a shift button mounted in a slot in the housing for limited alternate rotary movement about the axis of the spindle and connected to the shift washer for conjoint movement therewith, and cooperating cam means between the shift washer and the housing, whereby upon rotary movement of the shift washer, the shift washer moves axially to move the movable hammer member sufficiently away from the stationary hammer member to preclude engagement therebetween.
  • the housing includes a gear case cover having a bearing for journaling the rear portion of the spindle, and wherein the bearing is piloted concentrically within the stationary hammer member fixed in the gear case cover.
  • the housing includes a gear case cover having the spindle bearing mounted therein, and wherein an armature shaft is joumaled in a second bearing in the gear case cover, parallel to the axis of the spindle bearing, and wherein drive gearing means is disposed between the armature shaft and the spindle.
  • a portable power tool having two modes of operation, one for drilling and the other for hammer-drilling, selectively, comprising a motor housing, a gear case mounted forwardly of the motor housing, a gear case cover between the gear case and motor housing, an axially-retractable spindle joumaled in the gear case, a stationary hammer member fixed in the gear case cover, a movable hammer member carried by the spindle forwardly of the stationary hammer member, cooperating hammer elements formed on the hammer members, respectively, and adapted to engage each other in the hammer-drill mode of operation, a shift member positioned radially of the stationary hammer member, thrust bearing means between the shift member and the movable hammer member, means to rotate the shift member through an angle about the axis of the spindle, and cooperating cam means formed on the shift member and gear case cover, respectively, whereby rotation of the shift member causes an axial translation thereof, thereby moving the movable hammer member forwardly
  • shift button having a transverse slot formed therein, and the shift member having a radially-projecting tang received in the transverse slot.
  • the tool of claim 5 including means in the arcuate slot in the gear case cover to limit the alternate pivoted movement of the shift button, and further including means therein for providing a detent snap-action to movement of the shift button.
  • a portable power tool having two modes of operation, one for drilling and the other for hammer-drilling, selectively, comprising a motor housing, a gear case mounted forwardly of the motor housing, a gear case cover between the gear case and motor housing, an axially-retractable spindle joumaled in the gear case, a stationary hammer member fixed in the gear case cover, a movable hammer member carried by the spindle forwardly of the stationary hammer member, cooperating hammer elements formed on the hammer members, respectively, and adapted to engage each other in the hammer-drill mode of operation, a shift member positioned radially of the stationary hammer member, thrust bearing means between the shift member and the movable hammer member, means to rotate the shift member through an angle about the axis of the spindle, and cooperating cam means formed on the shift member and gear case cover, respectively, whereby rotation of the shift member causes an axial translation thereof, thereby moving the movable hammer member forwardly
  • a stationary hammer member comprising a flanged bushing fixed in the gear case cover, a bearing sleeve piloted concentrically within the flanged bushing, a spindle having a rearward portion joumaled in the bearing sleeve, a movable hammer member carried by the spindle and having notched teeth adapted to engage corresponding notched teeth on the flange of the bushing, a shift washer mounted concentrically of the bushing, means for rotating the shift washer through an angle about the axis of the spindle, means responsive to rotation of the shift washer to separate the corresponding notched teeth sufficiently to preclude their engagement, and detent means cooperating with the gear case cover for retaining the shift washer in a desired adjusted position.
  • a portable power tool adapted for drilling and hammer-drilling operations, respectively, and having a motor housing, a handle depending from the motor housing and adapted to be gripped by the operator, a motor in the motor housing and a switch on the handle for controlling the energization of the motor, a gear case mounted on the motor housing forwardly thereof, a gear case cover comprising an internal wall between the motor housing and the gear case, the motor having an armature shaft journalled in a bearing in the gear case cover, a spindle journalled in bearings in the gear case, one of the bearings being disposed in the forward portion of the gear case and the other in the gear case cover, a pinion on the armature shaft, gearing means in the gear case between the pinion and the spindle, a stationary hammer member fixed in the gear case cover radially of the spindle bearing, an axially-movable ham mer member carried by the rearward portion of the spindle and confronting the stationary hammer member in the gear case

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Drilling And Boring (AREA)
  • Percussive Tools And Related Accessories (AREA)
US00374565A 1972-07-13 1973-06-28 Hammer drill mechanism Expired - Lifetime US3835715A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB3274372A GB1432369A (en) 1972-07-13 1972-07-13 Hammer drill mechanism

Publications (1)

Publication Number Publication Date
US3835715A true US3835715A (en) 1974-09-17

Family

ID=10343350

Family Applications (1)

Application Number Title Priority Date Filing Date
US00374565A Expired - Lifetime US3835715A (en) 1972-07-13 1973-06-28 Hammer drill mechanism

Country Status (9)

Country Link
US (1) US3835715A (de)
JP (1) JPS599774Y2 (de)
AU (1) AU467588B2 (de)
CA (1) CA980153A (de)
DE (1) DE7324819U (de)
FR (1) FR2192894B1 (de)
GB (1) GB1432369A (de)
IT (1) IT990841B (de)
NL (1) NL7308918A (de)

Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5036926A (en) * 1990-08-02 1991-08-06 Ryobi Motor Products Corp. Power tool with improved bearing block
US5056607A (en) * 1989-05-25 1991-10-15 Black & Decker Inc. Mode change mechanism for power tools
US5447205A (en) * 1993-12-27 1995-09-05 Ryobi Motor Products Drill adjustment mechanism for a hammer drill
US5711379A (en) * 1995-05-29 1998-01-27 Makita Corporation Hammer drill
US6196076B1 (en) * 1998-10-29 2001-03-06 Chung Lee Hsin-Chih Knob switch device
US6789630B2 (en) * 2000-03-03 2004-09-14 Skil Europe B.V. Electric hand tool
US20040251039A1 (en) * 2003-06-12 2004-12-16 Helmut Burger Attachment member
US20060118314A1 (en) * 2004-12-02 2006-06-08 Bruno Aeberhard Hand-held power tool
US20090101376A1 (en) * 2006-05-19 2009-04-23 Black & Decker Inc. Mode change mechanism for a power tool
US20100026107A1 (en) * 2008-07-30 2010-02-04 Hitachi Kodki Co., Ltd. Power tool
US7717191B2 (en) 2007-11-21 2010-05-18 Black & Decker Inc. Multi-mode hammer drill with shift lock
US7717192B2 (en) 2007-11-21 2010-05-18 Black & Decker Inc. Multi-mode drill with mode collar
US7735575B2 (en) 2007-11-21 2010-06-15 Black & Decker Inc. Hammer drill with hard hammer support structure
US7762349B2 (en) 2007-11-21 2010-07-27 Black & Decker Inc. Multi-speed drill and transmission with low gear only clutch
US7770660B2 (en) 2007-11-21 2010-08-10 Black & Decker Inc. Mid-handle drill construction and assembly process
US7798245B2 (en) 2007-11-21 2010-09-21 Black & Decker Inc. Multi-mode drill with an electronic switching arrangement
US7854274B2 (en) 2007-11-21 2010-12-21 Black & Decker Inc. Multi-mode drill and transmission sub-assembly including a gear case cover supporting biasing
US20120234572A1 (en) * 2011-03-16 2012-09-20 Andreas Stihl Ag & Co. Kg Hand-Held Power Tool
US8636081B2 (en) 2011-12-15 2014-01-28 Milwaukee Electric Tool Corporation Rotary hammer
US20140069675A1 (en) * 2010-03-23 2014-03-13 Black & Decker Inc. Spindle bearing arrangement for a power tool
CN105437162A (zh) * 2014-06-30 2016-03-30 南京德朔实业有限公司 扭矩输出工具以及传动机构
US20160193726A1 (en) * 2014-12-04 2016-07-07 Black & Decker Inc. Drill
US9630307B2 (en) 2012-08-22 2017-04-25 Milwaukee Electric Tool Corporation Rotary hammer
US9862116B2 (en) 2014-11-20 2018-01-09 Black & Decker Inc. Dual speed gearboxes, transmissions, and apparatuses incorporating the same
US10328558B2 (en) 2014-12-04 2019-06-25 Black & Decker Inc. Drill
US20220314411A1 (en) * 2021-04-02 2022-10-06 Makita Corporation Power tool and impact tool

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19527117C2 (de) * 1995-07-25 2000-05-31 Metabowerke Kg Handbohrmaschine mit Einrichtung zum Umschalten der Betriebsarten "Bohren" und "Schlagbohren"

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2794621A (en) * 1951-06-11 1957-06-04 William D Sellers Drilling attachments
US3363700A (en) * 1965-08-24 1968-01-16 Millers Falls Co Rotary and hammer drill
US3433082A (en) * 1967-09-20 1969-03-18 Black & Decker Mfg Co Transmission and selector mechanism for alternate hammer and hammerdrill power tool
US3693728A (en) * 1969-11-15 1972-09-26 Reinhold Stroezel Percussion and rotary drilling machine
US3695365A (en) * 1969-11-14 1972-10-03 Bosch Gmbh Robert Torque and impulse transmitting machine

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL103649C (de) * 1957-11-26

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2794621A (en) * 1951-06-11 1957-06-04 William D Sellers Drilling attachments
US3363700A (en) * 1965-08-24 1968-01-16 Millers Falls Co Rotary and hammer drill
US3433082A (en) * 1967-09-20 1969-03-18 Black & Decker Mfg Co Transmission and selector mechanism for alternate hammer and hammerdrill power tool
US3695365A (en) * 1969-11-14 1972-10-03 Bosch Gmbh Robert Torque and impulse transmitting machine
US3693728A (en) * 1969-11-15 1972-09-26 Reinhold Stroezel Percussion and rotary drilling machine

Cited By (42)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5056607A (en) * 1989-05-25 1991-10-15 Black & Decker Inc. Mode change mechanism for power tools
US5036926A (en) * 1990-08-02 1991-08-06 Ryobi Motor Products Corp. Power tool with improved bearing block
US5447205A (en) * 1993-12-27 1995-09-05 Ryobi Motor Products Drill adjustment mechanism for a hammer drill
US5711379A (en) * 1995-05-29 1998-01-27 Makita Corporation Hammer drill
US6196076B1 (en) * 1998-10-29 2001-03-06 Chung Lee Hsin-Chih Knob switch device
US6789630B2 (en) * 2000-03-03 2004-09-14 Skil Europe B.V. Electric hand tool
US20040251039A1 (en) * 2003-06-12 2004-12-16 Helmut Burger Attachment member
US6957706B2 (en) * 2003-06-12 2005-10-25 Hilti Aktiengesellschaft Attachment member
CN100396445C (zh) * 2003-06-12 2008-06-25 希尔蒂股份公司 连接件
US8074735B2 (en) * 2004-12-02 2011-12-13 Robert Bosch Gmbh Hand-held power tool
US20060118314A1 (en) * 2004-12-02 2006-06-08 Bruno Aeberhard Hand-held power tool
US20090101376A1 (en) * 2006-05-19 2009-04-23 Black & Decker Inc. Mode change mechanism for a power tool
US8235137B2 (en) * 2006-05-19 2012-08-07 Black & Decker Inc. Mode change mechanism for a power tool
US8820430B2 (en) 2006-05-19 2014-09-02 Black & Decker Inc. Mode change mechanism for a power tool
US8555998B2 (en) 2007-11-21 2013-10-15 Black & Decker Inc. Multi-mode drill with mode collar
US7762349B2 (en) 2007-11-21 2010-07-27 Black & Decker Inc. Multi-speed drill and transmission with low gear only clutch
US7770660B2 (en) 2007-11-21 2010-08-10 Black & Decker Inc. Mid-handle drill construction and assembly process
US7798245B2 (en) 2007-11-21 2010-09-21 Black & Decker Inc. Multi-mode drill with an electronic switching arrangement
US7854274B2 (en) 2007-11-21 2010-12-21 Black & Decker Inc. Multi-mode drill and transmission sub-assembly including a gear case cover supporting biasing
US7987920B2 (en) 2007-11-21 2011-08-02 Black & Decker Inc. Multi-mode drill with mode collar
US7717192B2 (en) 2007-11-21 2010-05-18 Black & Decker Inc. Multi-mode drill with mode collar
US8109343B2 (en) 2007-11-21 2012-02-07 Black & Decker Inc. Multi-mode drill with mode collar
US7735575B2 (en) 2007-11-21 2010-06-15 Black & Decker Inc. Hammer drill with hard hammer support structure
US7717191B2 (en) 2007-11-21 2010-05-18 Black & Decker Inc. Multi-mode hammer drill with shift lock
US8292001B2 (en) 2007-11-21 2012-10-23 Black & Decker Inc. Multi-mode drill with an electronic switching arrangement
US8381835B2 (en) * 2008-07-30 2013-02-26 Hitachi Koki Co., Ltd. Power tool
EP2149432A3 (de) * 2008-07-30 2014-07-02 Hitachi Koki CO., LTD. Werkzeugmaschine
US20100026107A1 (en) * 2008-07-30 2010-02-04 Hitachi Kodki Co., Ltd. Power tool
US20140069675A1 (en) * 2010-03-23 2014-03-13 Black & Decker Inc. Spindle bearing arrangement for a power tool
US9216504B2 (en) * 2010-03-23 2015-12-22 Black & Decker Inc. Spindle bearing arrangement for a power tool
US20120234572A1 (en) * 2011-03-16 2012-09-20 Andreas Stihl Ag & Co. Kg Hand-Held Power Tool
US9220201B2 (en) * 2011-03-16 2015-12-29 Andreas Stihl Ag & Co. Kg Hand-held power tool
US9289890B2 (en) 2011-12-15 2016-03-22 Milwaukee Electric Tool Corporation Rotary hammer
USD791565S1 (en) 2011-12-15 2017-07-11 Milwaukee Electric Tool Corporation Rotary hammer
US8636081B2 (en) 2011-12-15 2014-01-28 Milwaukee Electric Tool Corporation Rotary hammer
US9630307B2 (en) 2012-08-22 2017-04-25 Milwaukee Electric Tool Corporation Rotary hammer
CN105437162A (zh) * 2014-06-30 2016-03-30 南京德朔实业有限公司 扭矩输出工具以及传动机构
US9862116B2 (en) 2014-11-20 2018-01-09 Black & Decker Inc. Dual speed gearboxes, transmissions, and apparatuses incorporating the same
US10328559B2 (en) * 2014-12-04 2019-06-25 Black & Decker Inc. Drill
US20160193726A1 (en) * 2014-12-04 2016-07-07 Black & Decker Inc. Drill
US10328558B2 (en) 2014-12-04 2019-06-25 Black & Decker Inc. Drill
US20220314411A1 (en) * 2021-04-02 2022-10-06 Makita Corporation Power tool and impact tool

Also Published As

Publication number Publication date
JPS4961184U (de) 1974-05-29
NL7308918A (de) 1974-01-15
FR2192894A1 (de) 1974-02-15
GB1432369A (en) 1976-04-14
DE7324819U (de) 1973-12-13
IT990841B (it) 1975-07-10
FR2192894B1 (de) 1978-12-29
JPS599774Y2 (ja) 1984-03-28
CA980153A (en) 1975-12-23
AU5722773A (en) 1975-01-09
AU467588B2 (en) 1975-12-04

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