US3447395A - Camshaft - Google Patents
Camshaft Download PDFInfo
- Publication number
- US3447395A US3447395A US646283A US3447395DA US3447395A US 3447395 A US3447395 A US 3447395A US 646283 A US646283 A US 646283A US 3447395D A US3447395D A US 3447395DA US 3447395 A US3447395 A US 3447395A
- Authority
- US
- United States
- Prior art keywords
- camshaft
- cams
- fastening means
- driving wheel
- cam
- 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
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
- F01L1/02—Valve drive
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
- F01L1/02—Valve drive
- F01L1/04—Valve drive by means of cams, camshafts, cam discs, eccentrics or the like
- F01L1/047—Camshafts
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H53/00—Cams ; Non-rotary cams; or cam-followers, e.g. rollers for gearing mechanisms
- F16H53/02—Single-track cams for single-revolution cycles; Camshafts with such cams
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H53/00—Cams ; Non-rotary cams; or cam-followers, e.g. rollers for gearing mechanisms
- F16H53/02—Single-track cams for single-revolution cycles; Camshafts with such cams
- F16H53/025—Single-track cams for single-revolution cycles; Camshafts with such cams characterised by their construction, e.g. assembling or manufacturing features
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H55/00—Elements with teeth or friction surfaces for conveying motion; Worms, pulleys or sheaves for gearing mechanisms
- F16H55/02—Toothed members; Worms
- F16H55/14—Construction providing resilience or vibration-damping
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
- F01L1/02—Valve drive
- F01L1/026—Gear drive
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C2360/00—Engines or pumps
- F16C2360/18—Camshafts
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C3/00—Shafts; Axles; Cranks; Eccentrics
- F16C3/02—Shafts; Axles
- F16C3/023—Shafts; Axles made of several parts, e.g. by welding
-
- 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
- Y10T74/21—Elements
- Y10T74/2101—Cams
Definitions
- a camshaft of the tubular type rotating on a fixed axle especially suitable for an internal combustion engine includes separately made sintered cams.
- the cams are fixed in invariable positions relative to one another on the shaft by means such as slots and tenons on the terminal portions of their axes.
- the toothed driving wheel may be similarly made for attachment to the terminal portion of an end cam.
- the wheel may include a plastics overcasting on its teeth.
- a camshaft of the tubular type burning around a fixed axle particularly for an internal combustion engine wherein at least each cam is constituted by a separate part obtained by sintering, angular ⁇ fastening means of the cams one with respect to the other'being arranged at the ends of each part to enable anFinvariable assembly of the" cams one after the other.
- FIG. 1 is a schematic view in elevation and in crosssection of one embodiment of a camshaft according to the invention.
- FIG. 2 is an end view of the camshaft of FIG. 1.
- this camshaft is of the tubular type turning around a fixed axle I mounted in an engine block or crank case, especially, for example, in an internal combustion engine.
- the camshaft shown comprises, in this example, only two cams 2 and 3 driven by a toothed wheel 4.
- Each of these cams 2 and 3 constitutes a separate part obtained by sintering.
- these fastening means comprise a group of slots 5 and of tenons 6 arranged at the ends of the members 2 and 3.
- the dimensions of the slots 5 and of the tenons 6 are selected so that their reciprocal engagement can only be effected in a particular angular position.
- the upper slot 5 is narrower than the other slots and only one tenon of corresponding dimension, arranged on the other part, can be engaged in this narrow slot 5, which ensures a single possible angular position of one cam 2 with respect to the other cam.
- the toothed driving wheel 4 of the camshaft is also obtained by sintering and forms itself a special member provided also with the group of slots 5 and tenons 6 which is adjacent to it.
- the latter has an overcasting 7 of plastics material to form the contact surface of its teeth 8.
- grooves 9 and 10 are channeled in the faces of the wheel 4 to ensure a good anchorage of the plastics overcasting material on the wheel 4.
- Angular fastening means for the different parts 2, 3, 4 are machined along the respective sides ensuring a force fit of the parts 2, 3, 4 one in the other, so as to avoid all angular play between these parts.
- a camshaft of the tubular type rotatable around a fixed axle particularly for use in an internal combustion engine, wherein at least each cam comprises a separate sintered part, angular fastening means connecting the cams one with respect to the other and arranged at the ends of each part to provide an invariable and inseparable assembly of the cams one after the other.
- a camshaft according to claim 1, wherein the fastening means comprises a group of slots and tenons designed to be engaged one in the other, the dimensions of the slot and tenons being selected so that their reciprocal engagement can only be effected in a particular angular position.
- a camshaft according to claim 1, wherein the fastening means comprises channels arranged in the ends of each part having a cam.
- a camshaft according to claim 1 including a toothed driving wheel connected by angular fastening means against the cams.
- a camshaft according to claim 1 including a toothed driving wheel having an overcasting of plastic material to form the contact surface of its teeth.
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Valve-Gear Or Valve Arrangements (AREA)
- Gears, Cams (AREA)
Description
June 3, 1969 H. c. E. LATOUR GAMSHAFT Filed June 15, 1967 INVENT OR HENRI C'HARLE5 Em mo 1.47001? ATTORNEY United States Patent 3,447,395 t CAMSHAFT Henri Charles Edouard Latour, Geneva, Switzerland, as-
signor to Motosacoche S.A., Geneva, Switzerland, a corporation of Switzerland Filed June 15, 1967, Ser. No. 646,283 Claims priority, application Switzerland, Sept. 13, 1966,
13,228/66 Int. Cl. F16]: 53/02 US. Cl. 74-567 10 Claims ABSTRACT OF THE DISCLOSURE A camshaft of the tubular type rotating on a fixed axle especially suitable for an internal combustion engine includes separately made sintered cams. The cams are fixed in invariable positions relative to one another on the shaft by means such as slots and tenons on the terminal portions of their axes. The toothed driving wheel may be similarly made for attachment to the terminal portion of an end cam. The wheel may include a plastics overcasting on its teeth.
It is an object of the present invention to provide a camshaft which can be manufactured at less expense.
Other objects and advantages of the invention will emerge from the detailed description below.
According to the invention there is provideda camshaft of the tubular type burning around a fixed axle particularly for an internal combustion engine, wherein at least each cam is constituted by a separate part obtained by sintering, angular {fastening means of the cams one with respect to the other'being arranged at the ends of each part to enable anFinvariable assembly of the" cams one after the other.
In order that the invention may be more fully understood one embodiment of a camshaft according to the invention will now be described more fully, purely by way of illustrative example, with reference to the accompanying drawings in which:
FIG. 1 is a schematic view in elevation and in crosssection of one embodiment of a camshaft according to the invention; and
FIG. 2 is an end view of the camshaft of FIG. 1.
Referring to the drawing, this camshaft is of the tubular type turning around a fixed axle I mounted in an engine block or crank case, especially, for example, in an internal combustion engine. The camshaft shown comprises, in this example, only two cams 2 and 3 driven by a toothed wheel 4. Each of these cams 2 and 3 constitutes a separate part obtained by sintering. By such a process of manufacture, cams, even of complex profiles, are easily manufactured and at little expense. 7
To ensure that the angular position of the cams 2 and 3 one with respect to the other is ensured in invariable manner, special fastening means are provided. In the example shown, these fastening means comprise a group of slots 5 and of tenons 6 arranged at the ends of the members 2 and 3. The dimensions of the slots 5 and of the tenons 6 are selected so that their reciprocal engagement can only be effected in a particular angular position.
As is seen in FIG. 2, the upper slot 5 is narrower than the other slots and only one tenon of corresponding dimension, arranged on the other part, can be engaged in this narrow slot 5, which ensures a single possible angular position of one cam 2 with respect to the other cam. 3 As is shown in the drawings, not only each cam 2 and 3, etc. forms a separate part, but also the toothed driving wheel 4 of the camshaft is also obtained by sintering and forms itself a special member provided also with the group of slots 5 and tenons 6 which is adjacent to it. Preferably and to avoid costly manufacture of this driving wheel 4, the latter has an overcasting 7 of plastics material to form the contact surface of its teeth 8. As is shown in'FIG. 1, grooves 9 and 10 are channeled in the faces of the wheel 4 to ensure a good anchorage of the plastics overcasting material on the wheel 4.
Numerous modifications of the angular fastening means of the cams 2, 3, etc. and of the toothed wheel 4 with respect to the latter could be envisaged. In place of using groups of slots 5 and tenons 6, grooves could be arranged axially or possibly radially in the ends of the parts 2, 3, 4.
Angular fastening means for the different parts 2, 3, 4 are machined along the respective sides ensuring a force fit of the parts 2, 3, 4 one in the other, so as to avoid all angular play between these parts. Once the different parts 2, 3, 4 are engaged one in the other, the total length of the camshaft is adjusted by turning of one of the ends of the latter.
It is understood without further description from the foregoing that such a method of manufacture of camshafts enables the cost price of the latter to be substantially reduced, being given the great rapidity of making each cam 2, 3, etc. itself, by sintering. Moreover, the overmoulding of plastics material 7 to form the contact surface of the toothing 8 facilitates also the provision of such an inexpensive denture of light weight, precise and silent. The teeth 11 in sintered material constitutes an additional reinforcement and anchorage for the teeth 8 of plastics material. The coefficient of expansion of the plastics material would not permit construction of the wheel 4 entirely of plastics material since the temperature in the crank case of the motor can vary about C.
Having particularly described the invention, it is to be understood that it is not to be considered limited to the details herein set forth but that various modifications and changes of the embodiment described will occur to those skilled in the art and these are to be regarded as within the scope of the invention as defined by the appended claims.
I claim:
1. A camshaft of the tubular type rotatable around a fixed axle particularly for use in an internal combustion engine, wherein at least each cam comprises a separate sintered part, angular fastening means connecting the cams one with respect to the other and arranged at the ends of each part to provide an invariable and inseparable assembly of the cams one after the other.
2. A camshaft according to claim 1, wherein the fastening means comprises a group of slots and tenons designed to be engaged one in the other, the dimensions of the slot and tenons being selected so that their reciprocal engagement can only be effected in a particular angular position.
3. A camshaft according to claim 1, wherein the fastening means comprises channels arranged in the ends of each part having a cam.
4. A camshaft according to claim 1, including a toothed driving wheel connected by angular fastening means against the cams.
5. A camshaft according to claim 4, wherein the toothed driving wheel is also sintered.
6. A camshaft according to claim 1, including a toothed driving wheel having an overcasting of plastic material to form the contact surface of its teeth.
7. A camshaft according to claim 5, wherein said toothed driving wheel has an overcasting of plastic material to form the contact surface of its teeth.
'8. A camshaft according to claim 6, wherein the toothed driving Wheel has channeled in its faces, grooves providing firm anchorage for said overcasting.
9. A camshaft according to claim 7, wherein said toothed driving wheel has channeled in its faces, grooves providing firm anchorage of said overcasting.
10. A camshaft according to claim 1, wherein said angular fastening means comprise grooves.
References Cited UNITED STATES PATENTS 10/1924 Luitwieler 74-567 6/ 1949 Essl 74-568 8/1965 Dew 74443 XR FRED C. MATTERN, JR. Primary Examiner.
F. D. SHOEMAKER, Assistant Examiner.
US. Cl. X.R.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH1322866A CH443785A (en) | 1966-09-13 | 1966-09-13 | Camshaft |
Publications (1)
Publication Number | Publication Date |
---|---|
US3447395A true US3447395A (en) | 1969-06-03 |
Family
ID=4390524
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US646283A Expired - Lifetime US3447395A (en) | 1966-09-13 | 1967-06-15 | Camshaft |
Country Status (6)
Country | Link |
---|---|
US (1) | US3447395A (en) |
AT (1) | AT268779B (en) |
BE (1) | BE703688A (en) |
CH (1) | CH443785A (en) |
DE (1) | DE1575572A1 (en) |
GB (1) | GB1131379A (en) |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4211192A (en) * | 1976-12-10 | 1980-07-08 | Sulzer Brothers Ltd. | Camshaft for an internal combustion engine |
US4638683A (en) * | 1984-06-18 | 1987-01-27 | Ngk Insulators, Ltd. | Camshaft for engine |
US4665766A (en) * | 1983-09-28 | 1987-05-19 | Nippon Piston Ring Co., Ltd. | Shaft member |
US4708029A (en) * | 1984-09-11 | 1987-11-24 | Nippon Piston Ring Co., Ltd. | Camshaft |
US4781075A (en) * | 1983-08-03 | 1988-11-01 | Nippon Piston Ring Co., Ltd. | Camshaft and method of making the same |
US5293847A (en) * | 1993-02-16 | 1994-03-15 | Hoffman Ronald J | Powdered metal camshaft assembly |
US5429080A (en) * | 1993-12-13 | 1995-07-04 | Evestar Technologies, Inc. | Compact internal combustion engine |
US6305242B1 (en) | 1998-09-04 | 2001-10-23 | Cummins Engine Company Ltd. | Camshaft alignment |
EP1288445A3 (en) * | 2001-08-29 | 2004-07-28 | Honda Giken Kogyo Kabushiki Kaisha | Valve-operating assembly of driven rotation member and cam |
WO2006074498A2 (en) * | 2005-01-17 | 2006-07-20 | Avl List Gmbh | Camshaft for an internal combustion engine |
WO2009056237A1 (en) * | 2007-11-02 | 2009-05-07 | Daimler Ag | Valve driving device |
CN102862102A (en) * | 2012-08-31 | 2013-01-09 | 浙江省平湖市工具厂 | Cam device of screw tap relief grinding machine |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1499946A (en) * | 1975-04-21 | 1978-02-01 | Dresser Ind | Crankshaft construction |
IT1180140B (en) * | 1984-11-19 | 1987-09-23 | Tecnamotor Spa | COMPOSITE TIMING SHAFT FOR ENDOTHERMAL ENGINES |
DE19738612A1 (en) * | 1997-09-04 | 1999-03-11 | Volkswagen Ag | Camshaft for internal-combustion engine |
DE19837385A1 (en) * | 1998-08-18 | 2000-02-24 | Joachim Gadau | Built-up camshaft composed of mutually centered cams adapters and pulleys using centering pieces and with center tie to hold all together in pre-tension |
DE102006013813B4 (en) | 2006-03-23 | 2011-05-12 | Mahle International Gmbh | Camshaft of particular motor vehicle internal combustion engines |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1512034A (en) * | 1923-07-09 | 1924-10-21 | Samuel W Luitwieler | Cam and spindle construction |
US2473417A (en) * | 1944-05-24 | 1949-06-14 | William H Harman Corp | Sectional shaft |
US3199364A (en) * | 1963-09-10 | 1965-08-10 | Morse Chain Co | Composite plastic gear |
-
1966
- 1966-09-13 CH CH1322866A patent/CH443785A/en unknown
- 1966-11-25 AT AT1092066A patent/AT268779B/en active
-
1967
- 1967-05-26 DE DE19671575572 patent/DE1575572A1/en active Pending
- 1967-06-15 US US646283A patent/US3447395A/en not_active Expired - Lifetime
- 1967-09-08 BE BE703688D patent/BE703688A/xx unknown
- 1967-09-11 GB GB41359/67A patent/GB1131379A/en not_active Expired
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1512034A (en) * | 1923-07-09 | 1924-10-21 | Samuel W Luitwieler | Cam and spindle construction |
US2473417A (en) * | 1944-05-24 | 1949-06-14 | William H Harman Corp | Sectional shaft |
US3199364A (en) * | 1963-09-10 | 1965-08-10 | Morse Chain Co | Composite plastic gear |
Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4211192A (en) * | 1976-12-10 | 1980-07-08 | Sulzer Brothers Ltd. | Camshaft for an internal combustion engine |
US4781075A (en) * | 1983-08-03 | 1988-11-01 | Nippon Piston Ring Co., Ltd. | Camshaft and method of making the same |
US4665766A (en) * | 1983-09-28 | 1987-05-19 | Nippon Piston Ring Co., Ltd. | Shaft member |
US4638683A (en) * | 1984-06-18 | 1987-01-27 | Ngk Insulators, Ltd. | Camshaft for engine |
US4708029A (en) * | 1984-09-11 | 1987-11-24 | Nippon Piston Ring Co., Ltd. | Camshaft |
US4761870A (en) * | 1984-09-11 | 1988-08-09 | Nippon Piston Ring Co., Ltd. | Method for making a camshaft |
US5293847A (en) * | 1993-02-16 | 1994-03-15 | Hoffman Ronald J | Powdered metal camshaft assembly |
WO1994019586A1 (en) * | 1993-02-16 | 1994-09-01 | Ryobi Outdoor Products, Inc. | Powdered metal camshaft assembly |
US5429080A (en) * | 1993-12-13 | 1995-07-04 | Evestar Technologies, Inc. | Compact internal combustion engine |
US6305242B1 (en) | 1998-09-04 | 2001-10-23 | Cummins Engine Company Ltd. | Camshaft alignment |
EP1288445A3 (en) * | 2001-08-29 | 2004-07-28 | Honda Giken Kogyo Kabushiki Kaisha | Valve-operating assembly of driven rotation member and cam |
WO2006074498A2 (en) * | 2005-01-17 | 2006-07-20 | Avl List Gmbh | Camshaft for an internal combustion engine |
WO2006074498A3 (en) * | 2005-01-17 | 2006-11-16 | Avl List Gmbh | Camshaft for an internal combustion engine |
WO2009056237A1 (en) * | 2007-11-02 | 2009-05-07 | Daimler Ag | Valve driving device |
CN102862102A (en) * | 2012-08-31 | 2013-01-09 | 浙江省平湖市工具厂 | Cam device of screw tap relief grinding machine |
Also Published As
Publication number | Publication date |
---|---|
AT268779B (en) | 1969-02-25 |
CH443785A (en) | 1967-09-15 |
DE1575572A1 (en) | 1970-01-29 |
BE703688A (en) | 1968-02-01 |
GB1131379A (en) | 1968-10-23 |
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