JPS5835419Y2 - Reciprocating motion control mechanism for impact power tools such as breakers - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a reciprocating control mechanism for an impact power tool such as a flaker driven by hydraulic pressure.

In other words, impact power tools such as breakers that are driven by hydraulic pressure are of the type that uses only the gas pressure sealed in the impact power tool in the impact stroke of the work tool such as a chisel, and the type that uses hydraulic pressure in combination or only with hydraulic pressure. There is something.

The present invention aims to provide a reciprocating motion control mechanism that is compact and operates reliably in the former type of impact power tool, and the present invention will be described below with reference to embodiments shown in the drawings.

Fig. 1 shows an impact power tool using the reciprocating control mechanism of the present invention, and the impact power tool 1 includes, from the left: a handle section A, a throttle valve section B, a reciprocating motion control mechanism section C, and a working tool section. Each of these will be explained in turn below.

First of all,...the center part A is a pair of upper and lower...center play)
11, 11' and this...endor plate 11°11
It consists of a grip 10 held in the sleeve.

The clip 10 has a metal grip bushing 12 fixed inside a cylinder made of vibration-proofing material such as rubber.
13, 13' according to the above...
fixed to the handle plate 11.11.

A lever 15 is attached to the lower handle plate 11 so as to be swingable by a shaft 18. It consists of a pin holding part 1γ extending to .

The handle part A has a pair of upper and lower handle plates 11.1.
1' is fixed to the main body 22 of the throttle valve section B, which will be described next.

Next, the throttle valve part B will be explained. The throttle valve part B has a substantially oval-shaped main body 22 and a throttle valve spool 25 built into the main body 22.

The throttle valve main body 22 supports the above-mentioned needle part A with a bolt 24 via a vibration-proof bushing 23 made of a vibration-proof material.

A spool 25 is housed in holes provided above and below on the right side of the throttle valve body 22, and the spool 25 can be slid upward by a pin holding portion 1γ of the lever 15 via a pin 19 that contacts the lower end. It has become.

The spool 25 has a recess 26 in the center, and the recess 26 is pushed to a lower end position by a spring 29 to allow the upper and lower input ports 21 and output ports 28 to communicate with each other.

The input port 2γ is located between the hydraulic oil passage from the inflow side metal fitting 31 to the inflow passage 35, and the output port 28 is located between the hydraulic oil passage from the inflow side metal fitting 31 to the inflow passage 35.
6 (in FIG. 1, the discharge path 36 and inflow path 35 appear to partially overlap) to the discharge side metal fitting 32 (in FIG. 1, the inflow side metal fitting 3
1) is located between the hydraulic oil passages to the

Next, the reciprocating motion control mechanism section C will be described. The mechanism section C includes a cylindrical main body 34, a high pressure gas chamber 68 provided on the left side of the main body 34, and a high pressure gas chamber 68 that is slidable left and right inside the main body 34. It has a piston 55 attached to the piston 55, and a cylindrical reciprocating control valve spool 50 attached to the outer periphery of the piston 55.

Further, in the upper interior of the main body 34, an inflow passage 35 and a discharge passage 35 that are continuous from the throttle valve portion B extend to the right, and are connected to an inflow port 40 and a discharge port 43 of a reciprocating control valve 44, which will be described below, respectively. They communicate through an inlet passage 35' and an outlet passage 36' bent at right angles.

Since the left end of the piston 55 protrudes into a high pressure gas chamber 68 filled with high pressure nitrogen gas, etc., the piston 55 is always forced to the right by gas pressure.

The reciprocating motion control mechanism of the present invention reciprocates this piston 55, and includes a high pressure gas chamber 68, a piston 55,
The reciprocating control valve 44 will be described in detail with reference to FIG. 2 below.

First, the piston 55 has a left small diameter part 5γ whose left end protrudes into the high pressure gas chamber 68, a right small diameter part 59, and a large diameter part 58 provided between these parts, and has a cylindrical main body. 34, and is accommodated in left and right cylinder chambers 56.degree. 56' separated by the large diameter portion 58 so as to be slidable left and right.

Next, the reciprocating control valve 44 includes a reciprocating control valve chamber 44' provided on the outer periphery of the piston 55, and a cylindrical reciprocating control valve spool 50 housed in the valve chamber 44' so as to be slidable left and right. Become.

The valve chamber 44' has a discharge port 43, a port 42, a port 41 . It has an inflow port 40 and a port 39.

The discharge port 43 is connected to the outflow passage 36', and the port 42 is connected to the outflow passage 36'.
is connected to the inflow path 35 through the oil path 42', the port 41 is connected to the cylinder chamber 56 through the oil path 45 and the cylinder port 46, the inflow port 40 is connected to the inflow path 35', the port 39 is connected to the oil path 49, Left and right cylinder chambers 5 via 4B
6' are each communicated with a cylinder port 4γ which opens to the right.

Next, from the right side, the reciprocating control valve spool 50 has an outer diameter of &
It has each part of p b y a y Cv d, and the size relationship of each part is c > d > a > b.

That is, from the outer diameter section a on the right end, to the recess 51 (outer diameter section), to the outer diameter section a again, to the outer diameter C section whose outer diameter is expanded by the pressure receiving surface 52, and to the outer diameter d whose outer diameter is reduced by the pressure receiving surface 53. Continuous with part-\.

Here, a groove 51 as shown in FIG. 3 is provided on the outer periphery at the right end of the center outer diameter section a, and a notch 54 is provided at the left end of the outer diameter section d.

Outer diameter of reciprocating control valve spool 50 a Ht) z a p
Each part of C14 and each port of reciprocating control valve chamber 44') 39, 4
0°41.42, 43 with reference to FIG. 2 when the spool 50 is at the right end position (R position) and FIG. 4 at the left end position (L position). explain.

First, in FIG. 2, the inlet port 4 is
0 and the port 39 are in communication, the pressure receiving surface 52 faces the port 41, the pressure receiving surface 53 faces the port 42, and the left end of the outer diameter section d is located on the right side of the discharge port 43.

Next, in FIG. 4, the right end outer diameter section a is the port 39.
The groove 51' allows the inflow port 40 and the port 41 to communicate with each other, and the left end of the outer diameter d portion contacts the left side surface of the port 43.

Although the configurations of the reciprocating control valve 44 and the piston 55 are as described above, returning to FIG. 1, a description of the high pressure gas chamber 68 will be added.

The high-pressure gas chamber 68 is sealed by a bushing 67, which has an eyelet forming a gas passage 66.

The gas passage 66 communicates with a gas supply port 63 via a gas passage 64, and the gas supply port 63 is sealed by a cover nut 62.

Next, the working tool part will be explained. The working tool part includes a cylindrical main body 10 and a chisel etc. whose left end is slidably housed in a hole in the main body 70 and contacts the right end of the piston 55. 71, and a spring γ that elastically supports the chisel etc. 71.
2.

The structure of the impact power tool using the reciprocating motion control mechanism of the present invention is as described above, and its operation will be explained below.

The initial state is as shown in Figs. 1 and 2, and the hydraulic oil supplied from the hydraulic pump (not shown) flows through the inflow side metal fitting 3.
However, since the throttle valve spool 25 is slid to the lower end by the spring 29, it flows from the recess 26 of the spool 25 to the output port 28 to the discharge side metal fitting 32. The piston 55 is not driven and remains slid to the right end due to the gas pressure in the high pressure gas chamber 68.

When the operator grips the lever grip part 16 from this initial state,
The lever holding portion 1γ of the lever 15 moves the throttle valve spool 25 upwardly against the spring 29 via the pin 19, and as a result, the input port 21 and the output port 28 are blocked by the throttle valve spool 25.

As a result, the hydraulic oil flows from the input port 2γ to the inflow path 35, further flows from the reciprocating control valve chamber 44 to the inflow port 40 via the inflow path 35', and from the oil path 42' to the port 42.

As the hydraulic oil flows to the port 42, supply pressure is applied to the pressure receiving surface 53 of the reciprocating control valve spool 50, and the spool 50 slides to the right end within the reciprocating control valve chamber 44' (see Figs. 1 and 2). is already in a sliding state).

Therefore, the hydraulic oil that has flowed to the inflow port 40 flows from the recess 51 to the cylinder port 47 via the oil passages 49 and 48, but as a result, supply pressure is applied to the right side of the large diameter portion 58 of the piston 55, and the piston 55 slides to the left against the gas pressure in the high pressure gas chamber 68.

At this time, the hydraulic oil in the left cylinder chamber 56 is supplied to the annular oil passage 38 between the reciprocating control valve spool 50 and the piston 55, the discharge port 43, the discharge passages 36' and 36, and the output port 28.
It is discharged from the discharge side metal fitting 32 via.

As the piston 55 slides to the left and the right end of the large diameter portion 58 passes through the cylinder port 46 which opens between the left and right cylinder chambers 56° 56' as shown in FIG. 4, the right cylinder chamber 56' is opened. The hydraulic oil inside flows from the port 46 to the oil passage 45.
Flows to port 41 via.

For this reason, supply pressure is applied to the pressure receiving surface 52 of the reciprocating control valve spool 50, and the force due to the supply pressure is greater than the force due to the supply pressure applied to the pressure receiving surface 53 as described above.
slides to the left within the reciprocating control Western-style room 44'.

Here, in the middle of sliding the reciprocating control valve spool 50 to the left, the ports 41 and 40 are communicated with each other by the spool 50 and the O groove 51, and as a result, the port 41 is separated from the right cylinder chamber 56'. Instead, supply pressure is applied from the port 40 as well, so that the spool 50 can be reliably slid to the left.

At the same time or immediately after the groove 51 of the spool 50 communicates the port 40 with the hoard 41, the outer diameter section a at the right end of the spool 50 blocks the inflow port 40 and the port 33, and as a result, the right cylinder chamber 56'~) The supply of hydraulic oil is stopped, and the leftward sliding movement of the piston 55 is stopped.

Next, almost at the same time as the inflow port 40 and port 39 are shut off, the right end of the spool 50 connects the port 39 and the cylinder chamber 56, so the right cylinder chamber 56' is connected to the cylinder port 4γ oil 148, 49 and the port 39. It communicates with the left cylinder chamber 56, but the cylinder chamber 56
is connected to the tank side through the annular oil passage 38 and the discharge port 43, so the pressure in the right cylinder chamber 56' also rapidly decreases to the tank pressure, and as a result, the piston 55 is moved by the gas pressure in the high pressure gas chamber 68. Start sliding to the right.

That is, the piston 55 is accelerated as follows, and finally its right end surface collides with the left end surface of the chisel etc. 11, giving an impact to the chisel etc. γ1.

Immediately before this collision, as shown in FIG.
6, the pressure within the port 41 is rapidly reduced, and the force that was pushing the spool 50 to the left on the pressure receiving surface 52 is reduced.

Therefore, the reciprocating control valve spool 50' slides to the right end within the reciprocating control valve chamber 44' due to the rightward pushing force of the supply pressure constantly applied to the pressure receiving surface 53, returns to the initial state, and returns to the left side of the piston 55. This will cause the sliding movement to begin.

The above operations of the reciprocating control valve spool 50 and the piston 55 are repeated continuously, and impact is continuously applied to the chisel etc. T1.

Now, the structure of the reciprocating motion control mechanism of the present invention shown in FIGS. 1 to 5 can be fully understood by paying attention to the following points.

(1) The reciprocating control valve spool 50 has a cylindrical shape and is attached to the outer periphery of the piston 55.

(2) The force to slide the reciprocating control valve spool 50 to the position where the piston 55 slides to the right is led from the cylinder port 46 that opens into the left and right 7 cylinder chambers 56, 56', This point is the force due to the supply pressure applied to the pressure receiving surface 52.

(3) When switching the reciprocating control valve spool 50 to a position where the piston 55 slides to the right, the hydraulic oil path is opened and closed in the following order.

3.1 A path is opened to the port 41 facing the pressure receiving surface 52 to introduce the supply hydraulic oil from a system different from the right cylinder chamber 56'.

3.2 At the same time or immediately after this, the right cylinder chamber 56'
Close the path leading hydraulic fluid to.

3.3 At about the same time, open a path that communicates the right cylinder chamber 56' of the large diameter portion 58 with the left cylinder chamber 56.

(4) The means for switching the reciprocating control valve spool 50 to a position where the piston 55 is slid to the left is to unseal the cylinder port 46 that opens between the left and right cylinder chambers 56 and 56' by the large diameter portion 58. This is achieved by communicating the port 41 facing the pressure receiving surface 52 with the tank side.

(5) The left cylinder chamber 56 is always communicated with the tank side.

(6) When the histone 55 slides to the right, the hydraulic fluid in the right cylinder chamber 56' once passes through the left cylinder chamber 56 and then returns to the tank.

(7) It is the force of the supply pressure applied to the pressure receiving surface 53 that causes the reciprocating control valve spool 50 to slide to the position where the piston 55 slides to the left.

The reciprocating motion control mechanism of an impact power tool such as a breaker driven by hydraulic pressure according to the present invention has the following effects in the above structure and operation.

(1) In the reciprocating motion control mechanism for an impact power tool such as a breaker of the present invention, the reciprocation control valve spool 50 is attached to the outer periphery of the piston 55, so that the impact power tool becomes compact.

(2) The reciprocating motion control mechanism of an impact power tool such as a breaker according to the present invention includes a cylinder port 46 that opens between the left and right cylinder chambers 56 and 56', and a port 41 that faces the pressure receiving surface 52.
The port 46 is connected to the right cylinder chamber 56.
The reciprocating control valve spool 50 is slid to a position where the piston 55 is slid to the right by opening the port 46 to the left cylinder chamber 56, and the spool 50 is moved to the opposite position by opening the port 46 to the left cylinder chamber 56. Since the piston 55 slides, it is possible to reliably move the piston 55 back and forth.

(3) When switching the reciprocating control valve spool 50 to a position where the piston 55 slides to the right, supply hydraulic oil from a system separate from the right cylinder chamber 56' is introduced to the port 41 facing the pressure receiving surface 52. To open the path 35'→40→51→41, the reciprocating control valve spool 50 is positively switched.

(4) When the piston 55 slides to the right, the hydraulic oil in the right cylinder chamber 56' flows into the left cylinder chamber 56, so the hydraulic oil in the right cylinder chamber 56' is smoothly discharged. Movement of the piston 55 to the right is not hindered.

(5) When the force due to the supply pressure applied to the pressure receiving surface 53 is used as the force to slide the reciprocating control valve spool 50 to the position where the piston 55 is slid to the left, the durability is greater than when a spring is used.

[Brief explanation of the drawing]

Fig. 1 is a front sectional view of an impact power tool using the reciprocating motion control mechanism of the present invention, Fig. 2 is a front sectional view of the reciprocating motion control mechanism in its initial state, and Fig. 3 is a front sectional view of the reciprocating control valve spool. 2. Figure 3-3 sectional view, Figure 4 is a front sectional view of the reciprocating control mechanism with the reciprocating control valve spool slid to the left end, and Figure 5 is the reciprocating control mechanism spool slid to the right end. FIG. 3 is a front sectional view of the reciprocating motion control mechanism. 1... Impact power tool, 10... Grip, 11, 1
1'... Handle plate, 12... Grip bush, 13, 13'... Bolt, 15... Lever 16... Lever grip part, 11... Pin holding part, 1
8... Shaft, 19... Pin, 22... Throttle valve body, 23... Anti-vibration bushing, 24 River bolt, 25
...throttle valve spool, 26...recess, 21.
...Input port, 28...Output port, 29...Spring, 31...Inflow side metal fitting, 32...Discharge side metal fitting, 3
4... Reciprocating motion control mechanism main body, 35.35'... Inflow path, 36, 36'... Discharge path, 38... Annular oil path, 39... Port, 40... Inflow port, 41
...Port, 42...Port, 42'...Oil path,
43... Discharge port, 44... Reciprocating control valve, 44'
...Reciprocating control valve chamber, 45...Oil passage, 46...Cylinder port, 4γ...Cylinder port, 48...
- Oil passage, 49... Oil passage, 50... Reciprocating control valve spool, 51... Recess, 51... Groove, 52... Pressure receiving surface, 53... Pressure receiving surface, 54... Notch, 55...Piston, 56...Cylinder chamber, 56'...Cylinder chamber, 5γ...Small diameter portion, 58...Large diameter portion, 59.
...Small diameter part, 62...Cover nut, 63...Gas supply port, 64...Gas path, 66...Gas path, 6γ・
... Bush 68... High pressure gas chamber, γ0... Work tool body, γ1... Chisel, etc., γ2... Work tool spring, A... Handle part, B... Throttle valve part,
C... Reciprocating motion control mechanism section, D... Work tool section.

Claims (1)

[Scope of utility model registration request] One end (hereinafter referred to as the left side) protrudes into the high-pressure gas chamber 68, the other end (hereinafter referred to as the right side) faces the chisel etc. 71, and the left side small diameter part 57, large diameter part 58 and Right small diameter section 5
9, and left and right cylinder chambers 56 and 56', which house the piston 55 in a slidable manner and are divided into left and right compartments by a large diameter portion 58, with the left chamber always communicating with the tank side. , has both a position where the piston 55 slides to the left (hereinafter referred to as the R position) and a position where the piston 55 slides to the right (hereinafter referred to as the down position). The path leading to the left and right cylinder chambers 56' is opened, and the left and right cylinder chambers 56' are opened at the L position.
56' are communicated with each other, and the left and right cylinder chambers 56, 56'
A pressure receiving surface 52 to which a force is applied in one position direction at the port 41 communicating with the cylinder port 46 opened in the middle of the
When sliding from the L position to the R position, a path is opened to the port 41 for introducing the supply hydraulic oil from a system different from the cylinder port 46, and at the same time or immediately after this, the right cylinder The path leading the hydraulic oil to the chamber 56' is closed, and at the same time, the path communicating between the left and right cylinder chambers 56 and 56' is opened, and the piston 55 is always pressed in the R position direction by the pressure of the supplied hydraulic oil. A reciprocating motion control mechanism for an impact power tool such as a plate, which is composed of a cylindrical reciprocating control valve spool 50 attached to the outer periphery so as to be slidable left and right.