DE1628056B - Rotary hammer with percussion piston working as a free piston. Elimination from: 1427747 - Google Patents

Description

3 4

normally achievable maximum percussion pitch 32 has a bore 33 with an octagonal

by additional charging of the pneumatic cross-section. A fixed in the housing part 12

Buffer takes place. According to the invention, this is because ring 38 takes place in its through-hole 39

achieved by that these ventilation openings in the loading an insert ring 41, which extends radially

rich of the front dead center of the drive piston 5 outwardly extending circumferential flange 42 and a

are provided such that they are radially inwardly extending circumferential flange during the rear

upward movement of the drive piston are open 43 has. The insert ring 41 is on its inner

and closed by the percussion piston and fitted with a guide ring 44 on the side by a snug fit.

after the start of the working stroke of the drive piston, the inner cross section 45 of which is an octagonal

through the percussion piston when it is in its back shape. One of the task forces 48

most westerly location are closed. Mende terminating sleeve 52 is with its end 53 with

The invention makes use of the fact that the inside of the insert ring 41 is screwed and that, due to its inertia, the impact piston simultaneously presses the guide ring 44 against the wheel drive piston during the stroke movements of the circumferential flange 43 protruding inwardly. hurries This creates an overpressure during the forward stroke of the drive piston, and a through-opening stroke of the drive piston shows a negative pressure on the return 54 of the closing sleeve 52. During voltage 55, which runs from the inside to the outside of this latter phase, in which the percussion piston of the percussion drill lies in its front stroke area corresponding to the shoulder, is thus tapered through 49 of the insert shaft 48,
the negative pressure through the arrangement according to the invention. 20 The additional air on the pin 82 of the eccentric disk 77 by means of the ventilation openings in the connecting rod 65 attached to a bushing 83 is sucked in by means of pneumatic buffers, so that two connecting rod bearings 67 and one connecting rod pin 66 with steren Phase in which the ventilation openings in the drive piston 64, which runs back and forth in the cylinder liner 26 and the rear position of the percussion piston closed, are connected. The piston 64 is sen, this additionally charged pneumatic 25 stores additional energy by means of two sealing rings 68 against the cylinder buffer, which is sealed to a we- liner. Between the drive piston, the significantly greater acceleration of the percussion piston 64 and the cylinder liner on the bearing ring 27, which closes the drive after overcoming the inertia forces and thus on the opposite side, results in a much greater percussion effect. a free-flying percussion piston 58 in the cylinder

In order to achieve an even more favorable control effect and a bushing 26 which is sealed against the cylinder liner by means of a seal further improving the charging of the buffer to ring 61. the percussion piston can achieve such a The percussion piston 58 has a recess 59, have a stroke that it is in its rear dead center, which receives a percussion insert,
After the start of the working stroke of the drive piston, the cylinder liner 26 has an opening 100;
drive piston exceeds. The collecting space 96 between the cylinder liner 26

The invention will be described in the following with reference to the and housing 12 opens out via an opening 98 in

Drawings explained in more detail. In the drawings a channel 97 open to the atmosphere.

shows '' On the front opposite the drive

F i g. 1 shows a longitudinal section through a rotary 40 side of the cylinder liner 26 in the immediate vicinity

hammer according to the invention, 'near the bearing ring 27 a number of openings

Fig. 2 to 5 partial longitudinal sections, the drive and 95 and at a distance from these to the rear one

Represent the percussion piston in individual stroke positions. Number of openings 124 on the circumference of the cylinder

The best-linder bushing 26 from the housing parts 12, 13 and 14 is arranged. The openings 95 and

The rotating percussion hammer 10 has a handle 45 124 connecting the space between the percussion piston 58

15 with a switch 76 for the supply line 75 and bearing ring 27 with the collecting space 96.

on; in the housing 13 is the one in bearings 72, 73. A narrow vent opening 100 is in the cylinder

Motor 70 mounted with an impeller 74 on the cylinder bushing 26 immediately in front of the piston crown

Shaft 71 attached. Via a pinion 78 on the drive piston 64 prior to its designated by xx

Shaft 71 becomes a 50 th front dead center which has a ring gear 79.

in the bearings 81, 84 mounted eccentric 80. It is now the mode of operation of a

the percussion drill operated on the opposite side of the tooth pneumatic cushion

wreath 79 has a pinion 86, which is explained in more detail about a toothed machine.

wheel 87 ends in a bevel gear 92 and in Fig. 1, the drive piston 64 is at the end point

drives the bearings 90, 89 mounted shaft 88, the 55 of its return stroke is shown. The front dead center

in turn, the drive piston 64 fastened on the cylinder liner 26 is shown in FIG.

Bevel gear ring 24 offset in rotation. chelte line xx indicated and in F i g. 2 shown.

The cylinder liner 26 is on the one hand with the Ke- The impact piston 58 is in Fig. 1 and 2 in the impact gel wheel rim 24 in one in an annular groove 21 on the inside engagement with the end of the striking tool 46 of the housing part 12 arranged bearing 60 shows. At the moment of Strike 22 Impact engagement and on the other hand, via a piston 58 pushed into it, there is the drive piston 64 per bearing ring 27 in a ball seated in an annular groove 18 but the one in FIG. 1 position shown on the front bearing 19 stored. Dead center. By the return stroke of the drive piston

The bearing ring 27 has a through hole 64 is formed between the drive piston 64 and

30 and a peripheral flange 36, on which 65 the percussion piston 58 a vacuum. The one between the a rubber seal 35 is located, which through the impact side of the percussion piston 58 and the bearing ring

the bearing ring 27 screwed in a thread 37 accelerated 27 prevailing atmospheric pressure

face insert 32 is clamped. The insert - the percussion piston 58 and lets him do the return stroke

5 6

The movement of the drive piston 64 follows with a delay

The drive piston 64 starts with its .Vorhub, the prevailing atmospheric pressure due to the

the percussion piston 58 sets its movement in motion between the two pistons 58, 64

ttmg to the drive piston 64 initially .still continue, so Unterdrackes pushed after the drive piston 64

"that 'the between the two pistons 58, 64 entered 5 and additional air through the opening Ϊ00

s'chlosserie Air compressed and sucked in with high grain. Even after the start of the forward stroke of the

primed ,, is. This Dpick serves as a buffer as well as 64 sets the impact piston 58 its position.

as for the transmission of the driving force. Pay attention to the compression movement on the drive piston. 64 in

The pressure of the air reverses the direction of movement of the sequence of the forces of measure. (Fig. 5)

Percussion piston 58 around. The .., percussion piston 58 moves the air in a way that prevents it. Beneficial

now in the direction of the tool side / the hammer, the two pistons ″, the direction of movement rotates

me'rs 10 with a very, high acceleration and impact piston and lets him through 'die as a result

"apply a strong blow." against; the striking tool "opening 100" additionally charged buffer

/ Ϊ6 from, "owing to the high pressure which" between the high _ 'speed against _; the striking tool

Schlägkolben.58 and "the Antxiebsko'lben: 64 currency ih auischla'gen'QFi'g 2) JST been found that..

.fend .des-Voxhutes "des / Antnebskolberis" with.equivalent; - 'the' oblique Tiizw. .'Work hat) Ses Schlagkolberis 58

early guardianship or 'Standstill of the percussion piston%? §T' in your 'Aicrgonbyck / initiated "wad,; in. Vyelchem

is being built. Wäfcend the return stroke 'des / üi- [d'e "r .Äntrie'b" skolben_ 64 approximately,' two thirds of his

iriebskolbens 64 ~ Wd / through "the ventilation opening VotliuiieS has passed [F i ^: g. 5),

, 100. ^ msequence ^ 'of the delay. "the. movement _{#> of} the a'o _(the .important. zuin. diameter of the cy-

.Schläglcplbens "58. Additional air in the cylinder. The small opening 100 is located in the cylinder

^ sleeve 26 "sucked in to avoid air loss during cylinder sleeve 26 '' unmiffelbar before the" .dem drive

of 'working stroke .des. ! Drive.pistons, 64 disengaged - 'turned away.

; chen and lbei '"deVHub ^£ ümk'" or the forward movement ^ front dead tract; of the VprhUbes (Fig. 2). Therewith

'which are between the list "of the percussion piston"and' ^ the 'opening 100 e'mges ^: aug't zwis'cn'eii; your Sctilagkolnüngea 95 ϊί-ρ & ΏΑ, άζη. Collecting room 96, "the openings 58 and the / drive pin ^! "64 is, as in Fig. 5 only. 98 and 'the channel 97" in ", the ₍ atrno" sphere outside 30 "shown,' the opening 100, pushing through the percussion piston, so'ä'äß ^ to "the list" no "the blow ^ 8 vordeckt ^,,,: no so'daß L'uft'durch the opening ■ riemmerider'Gegendruckentste.ht, _ _ iobenfw"eic; he) can i...... The size of the opening 100 "ibt

^ In Fi g. 2 ^ is. the / percussion piston 58 .. 'iii Sclilägein- / for / the exact pneumatic mode of operation' der ^: griff "with your percussion tool ^: shown. / The from Mo- _ Schiägvorrichtung is important, because the; quantity / 'äer 10 ^ 7O ₁ driven Aütriebskplben '64 Tiefmäet to äaxgestellt "35 sucked air for 'Ae K n ^ efficiency üs'schlägge Jn-Pig-2 on yörderen dead center" of its Vofhubes. Bend. for example, at amounts eiüein Tünen-As in Ki g. ^, wif d. 'the / percussion piston 58' diameter of the "cylinder: 26 of '635 now' that after the start of the return stroke" of the drive piston '64 "diameter of the opening 1001.6 mm.

1 sheet of drawings

Claims (2)

one or both cylinder ends and the pneumatic patent claims: table buffer can take place and thereby the energy transfer of the pneumatic buffer is controlled 1. Rotary hammer with one in one ro- can be. In a similar known arranger Cylinder with the interposition of 5 voltage (USA patent 1954411) takes place a pneumatic buffer from the motor via control of the bypass lines through the a drive piston into a reciprocating percussion piston itself, the connecting opening supply drivable, working as a free piston between the bypass lines and the Impact piston and, in connection with the atmosphere, pneumatic buffers only in the foremost dead center The air vents in the cylinder in the io of the percussion piston are open. Known by this Area of this pneumatic buffer, the measure should be achieved that the drive through characterized in that this air piston, when the percussion piston has reached the front opening (100) in the area of the front dead center, without any further effort Can move forward dead center of the drive piston (64) to its front dead center, are seen that they are during the backward movement. However, this known arrangement requires the emergency route of the drive piston (64) are open agility to take special precautions and the impact piston is closed by the impact piston (58) during the return stroke of the drive piston and after the beginning of the working stroke of the ben so far, until the connecting opening drive piston; (64) through the impact piston openings between the pneumatic buffer and over- (58), if this bridge lines are closed in its rearmost position 20. Also will are closed. by this known arrangement of the pneumatic 2. Rotary hammer according to claim 1, the buffer is very thin, so that it is not used as an energy storage device characterized in that the percussion piston (58) rather during the forward stroke of the drive line has such a stroke that he is in his bens as long as the percussion piston by his mass rear Dead center, which has not yet been set in motion after the beginning of the working inertia, are used stroke of the drive piston (64) is reached, can. the front dead center of the drive piston (64) Another known arrangement (German Pa- exceeds. tentschrift 720150) avoids a too strong Ab construction of the pneumatic buffer in the event that air escapes through leaks, in that slots are provided in the cylinder through which the At the end of the stroke when the drive piston falls, the air buffer space is balanced with the atmospheric one The invention relates to an air hammer. In this known arrangement with one in a rotating cylinder below between 35 that is in the area of the rear dead center of the circuit switching of a pneumatic buffer from the drive piston connects to the atmospheric engine Made via a drive piston in a back and forth sphere, so that in the event that in this Drivable reciprocation, work as a free piston- position a negative pressure in the pneumatic buffer Percussion piston and understood with the atmosphere, the air losses are replaced. With the bond standing vents in the cylinder 40 chen known arrangement can also in place of the pneumatic buffer. the slots the buffer space compressed air from a A major problem with those with a free compressed air source are supplied, this measuring piston drive working rotary percussion hammers would also lead to a regulation of the impact effect in that that can be used between the drive piston and. Free piston and the "between the free piston and 45 In other known hammers (USA. Patent of the front end face of the cylinder formed air writing 1461460 and German utility model pad not only acceleration but also 1768 865) it is known that the impact effect thereby decelerating forces on the Exercise free piston. In order to influence that the pneumatic buffer during these deceleration forces, as far as they affect the transmission end of the entire piston movement optionally with the impact energy disadvantageously, .possible to largely switch off the atmosphere under control of a valve, it is known to set a ventilation connection, whereby When opening the openings in the area of movement of the impact valve, the impact effect is interrupted,
To attach piston serving free piston, which all these known arrangements, as far as they the impact dampening air cushions into the atmosphere - an influencing of the impact effect to the opposing sphere vent. - _: ■. ■ .55 stand, use either an additional There are also rotary impact hammers of the initially compressed air source for additional charging of the mentioned type known in which the between the pneumatic buffer or they reduce the Drive piston and percussion piston lying pneumatic maximum impact effect, which without the influences Buffer itself to influence the between sungseinffekt is attainable by appropriate energy transmitted by the two pistons with the atmo- 60 weakening by discharging the pneumatic Sphere is connectable. ·. Buffers. In order to influence the impact So it is known (US Pat. No. 879 828), the known arrangements are so expensive to achieve an additional devices through the pneumatic action in the cylinder or they regulate down, the unimpeded movement of the piston, ie they reduce the impact against Zero,
a transmission controlled by a free travel valve. The application line between the pneumatic buffer, on which the invention is based, would be to design a rotary hammer of the type mentioned at the beginning and the two outer ends of the cylinder in such a way that there is no additional equipment, so that an exchange of air optionally between services, such as a compressed air source, an increase in