Tool driving or impacting – Impacting devices – With impact cushioning means
Patent
1998-01-02
1999-07-13
Smith, Scott A.
Tool driving or impacting
Impacting devices
With impact cushioning means
1731622, 173128, 173170, B23B 4516
Patent
active
059213272
DESCRIPTION:
BRIEF SUMMARY
This invention relates to a pneumatic impact tool of the type comprising a tubular housing with a rear section, an intermediate section, and a front section, wherein the intermediate section is formed with a cylinder bore in which is reciprocably guided a hammer piston with a forward impact delivering neck portion, a valve means disposed in the rear housing section for distributing motive pressure air to the cylinder bore to reciprocate the hammer piston therein, and a guide sleeve mounted in the cylinder bore for guidingly supporting the rear impact receiving shank portion of a working implement.
BACKGROUND OF THE INVENTION
Tools of the above type are oftenly used for breaking and rock drilling purposes and develop a high impact power to effectively carry out the intended work. However, high impact power also means that the tool housing as well as the components of the impact mechanism are subjected to severe strain during operation, and that the entire tool has to be of a rugged design. This means in turn that the tool tends to be rather large in size and heavy, which is a drawback when used in hand held applications.
Another reason why prior art tools of this kind tend to be rather heavy and bulky is that the housings comprise two or more parts which are held together by heavy duty screw joints, for instance in the form of lateral tie bolts. See SE 424522, EP 150170 and U.S. Pat. No. 2,558,165.
Some common types of prior art impact tools comprise housings in which the cylinder bore has a damping shoulder formed by a decreased diameter portion in the housing. This arrangement requires a rather complicated and costly working of the cylinder bore. An example of such a tool design is shown in EP 150170.
To avoid the above costly working requirement concerning the tool housing it has been previously suggested to form the tool housing with a constant diameter cylinder bore. See U.S. Pat. No. 2,558,165, 3,847,232, and 4,308,926. However, the impact tools shown in these patents still include heavy duty type threaded joints for the assemblage of tool housing parts and for mounting of separate working implement retainers and handles.
OBJECT OF THE INVENTION
It is a primary object of the invention to accomplish a pneumatic impact tool ox the initially mentioned type having a housing of an overall lighter and slimmer design.
Another object of the invention is to accomplish a pneumatic impact tool which comprises a housing of a simplified and less costly design.
Further objects and advantages of the invention will appear from the following detailed specification.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment is hereinbelow described in detail with reference to the accompanying drawings.
In the drawings:
FIG. 1 shows a longitudinal section through an impact tool according to the invention.
FIG. 2 shows a longitudinal section through the tool in FIG. 1 but referring to a plane perpendicular to the section in FIG. 1.
FIG. 3 shows, on a larger scale, a fractional section through the rear part of the tool housing as illustrated in FIG. 1.
DETAILED DESCRIPTION
The impact tool illustrated in the drawing figures is a pneumatic hand held tool of the breaker type which is intended primarily for demolition work, such as concrete and asphalt breaking and hole making.
The tool comprises a tubular housing 10 with a longitudinal cylinder bore 11 for reciprocably guiding a hammer piston 12. The latter is formed with an impact delivering neck portion 13 for cooperation with the rear impact receiving shank portion of a working implement (not shown).
At the rear end of the housing 10, there is disposed an air distribution valve 14 which is arranged to feed motive pressure air into the cylinder bore 11 to reciprocate the hammer piston 12 therein. The valve 14 communicates with the rear end of the cylinder bore 11 via a forward directed opening 15 and with a central part of the cylinder bore 11 via a passage 16. The latter extends in parallel with the cylinder bore 11 and is connected to a rear end opening 17 of t
REFERENCES:
patent: 2558165 (1951-06-01), Anderson
patent: 3179185 (1965-04-01), O'Farrell
patent: 3275089 (1966-09-01), Kaiser
patent: 3847232 (1974-11-01), Klushin et al.
patent: 4303131 (1981-12-01), Clark
patent: 4308926 (1982-01-01), Montabert
patent: 4576241 (1986-03-01), Emonet
patent: 5056606 (1991-10-01), Barthomeuf
patent: 5511800 (1996-04-01), Drumheller
patent: 5524715 (1996-06-01), Kimberlin
Henriksson Stig Roland
Nilsson .ANG.ke Lennart
Atlas Copco Berema AB
Calve James P.
Smith Scott A.
LandOfFree
Pneumatic impact tool having an integrally formed one-piece hous does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Pneumatic impact tool having an integrally formed one-piece hous, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pneumatic impact tool having an integrally formed one-piece hous will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2267942