JP4901292B2 - Hydraulic drive device and pinch processing device equipped with the same - Google Patents

Description

  The present invention relates to a technique for driving a pinching device such as a crusher or a press by a hydraulic actuator such as a hydraulic cylinder.

  2. Description of the Related Art Conventionally, as a pinching processing device that is opened and closed using a hydraulic actuator, for example, a crusher that is attached to the tip of an attachment support portion of a work machine is known. The crusher includes a crusher main body attached to the attachment support portion and a pair of crushing arms rotatably connected to the crusher main body, and the crushing arms rotate in directions opposite to each other. Open and close by. And at the time of the operation | movement of the closing direction, a processed material is inserted | pinched between the said crushing arms, and this is crushed.

  The hydraulic actuator is used to open and close the crushing arm. The higher the driving speed, the higher the work efficiency. However, the drive speeds of the hydraulic actuator and the crushing arm are determined by the capacity and discharge pressure of the main hydraulic pump that supplies hydraulic oil to the hydraulic actuator. Therefore, in order to obtain a higher driving speed with the limited pump capacity and pump discharge pressure, it is necessary to interpose a speed increaser between the main hydraulic pump and the hydraulic actuator.

As specific means, for example, in Patent Document 1 below, a part of the return oil flowing out from the rod side chamber is supplied to the supply side by utilizing the area difference between the head side chamber and the rod side chamber of the hydraulic cylinder to be driven. There has been disclosed a speed increaser that increases the supply flow rate to the head side chamber by constructing a regeneration circuit for reduction.
Japanese Patent Laid-Open No. 10-169213

  The speed increaser disclosed in Patent Document 1 has a problem that the degree of freedom in design is very narrow for the following reason.

  1) Since the area difference between the head side chamber and the rod side chamber of the hydraulic cylinder is utilized, its use is limited when the hydraulic cylinder is extended. Therefore, it is difficult to apply to driving in the contracting direction of the hydraulic cylinder and driving hydraulic actuators other than the hydraulic cylinder.

  2) The regeneration amount of the oil is limited, and the range in which the speed increase rate can be set is extremely narrow.

  In view of such circumstances, an object of the present invention is to provide a hydraulic drive device that has a high degree of freedom in design and that can effectively increase the speed without increasing the capacity of a main hydraulic pump.

As means for solving the above-mentioned problems, the present invention provides a hydraulic drive apparatus comprising a hydraulic actuator, a main hydraulic pump, and a hydraulic circuit that connects the main hydraulic pump to the hydraulic actuator to operate the hydraulic actuator. The hydraulic circuit includes a hydraulic motor that operates when the discharge oil of the main hydraulic pump is supplied, an input shaft connected to the output shaft of the hydraulic motor, and the hydraulic circuit is driven by the hydraulic motor. An auxiliary hydraulic pump that sucks and discharges the oil, an introduction part that introduces the discharge oil of the main hydraulic pump into the hydraulic motor, and the oil that flows out of the hydraulic motor and the discharge oil of the auxiliary hydraulic pump are joined together the includes a converging portion leading to the hydraulic actuator, and a oil return back to the tank flowing out the hydraulic actuator, the merging unit merges Which comprises one of the first supply position for supplying to the input port of the oil the hydraulic actuator, the confluence supply switching valve the merged oil and a second supply position for supplying to the other input port of the hydraulic actuator It is.

  According to this configuration, when the discharge oil of the main hydraulic pump is supplied from the main hydraulic pump to the hydraulic motor, the hydraulic motor is activated to drive the auxiliary hydraulic pump connected to the hydraulic motor. . By this driving, the auxiliary hydraulic pump sucks and discharges the hydraulic oil in the tank. Then, the oil discharged from the auxiliary hydraulic pump and the oil flowing out from the hydraulic motor are merged and supplied to the hydraulic actuator, so that the hydraulic actuator is not expanded without increasing the capacity of the main hydraulic pump. The flow rate supplied can be increased. Therefore, even if the capacity of the main hydraulic pump is limited, the hydraulic actuator can be effectively driven at an increased speed.

  In addition, unlike the regeneration circuit described in Patent Document 1, the speed increasing mechanism according to the present invention is not limited by the type of hydraulic actuator and the driving direction. Further, since the speed increasing ratio can be changed by selecting the hydraulic motor and the auxiliary hydraulic pump, the degree of freedom of setting is relatively high.

Specifically, a first supply position for supplying the joined oil to one input port of the hydraulic actuator to the joining portion, and a second supply position for supplying the joined oil to the other input port of the hydraulic actuator. By providing a merging supply switching valve having a supply position, it is possible to obtain a speed increasing effect by the hydraulic motor and the auxiliary hydraulic pump for bidirectional driving of the hydraulic actuator.

The hydraulic motor and the auxiliary hydraulic pump may be dedicated for use only as a motor and a pump, respectively, but the first pump motor and the second pump motor that can be used as the hydraulic motor and the auxiliary hydraulic pump. The introduction section includes a first introduction position for connecting an inlet side of the first pump motor to the main hydraulic pump and connecting an inlet side of the second pump motor to a tank, and the second An introduction switching valve that is switched to a second introduction position that connects the inlet side of the pump motor to the main hydraulic pump and connects the inlet side of the first pump motor to the tank, a first pilot unit which pilot pressure for switching the confluence supply switching valve to the first supply position is inputted, the confluence supply switching valve to the second supply position A pilot switching valve having a second pilot portion to which a pilot pressure for switching is input, wherein the first pilot portion is connected to an inlet side of the first pump motor, and the second pilot portion is What is connected to the inlet side of the second pump motor is more preferable.

  According to this apparatus, by switching the introduction position of the introduction switching valve, the position of the merging supply switching valve is used while the first pump motor and the second pump motor are both used as a hydraulic motor and an auxiliary hydraulic pump, respectively. Thus, the speed increasing effect of the two pump motors can be exhibited in the bidirectional driving of the hydraulic actuator.

  Specifically, when the introduction switching valve is switched to the first introduction position, the discharge oil of the main hydraulic pump is introduced into the first pump motor, whereby the first pump motor becomes the hydraulic motor. The second pump motor is linked to the first pump motor and functions as the auxiliary hydraulic pump. On the other hand, when a part of the oil supplied to the first pump motor is supplied to the first pilot portion of the merging supply switching valve, the merging supply switching valve is switched to the first supply position. . As a result, the combined oil of the oil discharged from the first pump motor and the oil discharged from the second pump motor is supplied to one input port of the hydraulic actuator.

  On the other hand, when the introduction switching valve is switched to the second introduction position, the discharge oil of the main hydraulic pump is introduced into the second pump motor, so that the second pump motor becomes the hydraulic motor. The first pump motor is linked to the second pump motor and functions as the auxiliary hydraulic pump. On the other hand, when a part of the oil supplied to the second pump motor is supplied to the second pilot section of the merging supply switching valve, the merging supply switching valve is switched to the second supply position. . As a result, the combined oil of the oil discharged from the second pump motor and the oil discharged from the first pump motor is supplied to one input port of the hydraulic actuator.

  The hydraulic circuit further includes a bypass oil passage for bypassing the hydraulic motor and the auxiliary hydraulic pump to guide the discharge oil of the main hydraulic pump to the hydraulic actuator, and the hydraulic pressure on the inlet side of the hydraulic motor is It is more preferable to include a bypass switching valve that guides the discharge oil of the main hydraulic pump to the bypass oil passage side when it is above a certain level.

  According to this configuration, when the drive load of the hydraulic actuator rises and the hydraulic pressure on the inlet side of the hydraulic motor becomes equal to or higher than a certain level, the discharge oil of the main hydraulic pump causes the hydraulic motor and the auxiliary hydraulic pump to By directly supplying the hydraulic actuator through a bypass oil passage that bypasses the speed increasing mechanism including the speed increasing mechanism, the operation can be switched to an operation that prioritizes securing the driving force over the speed increasing operation.

The present invention also includes a first sandwiching member and a second sandwiching member that move relative to each other in the opening / closing direction, which is a direction in which they are contacted and separated from each other, and sandwich the workpiece when moved in the closing direction, and drive the opening / closing of these sandwiching members. The hydraulic drive device according to any one of claims 1 to 3 , and the sandwiching members such that the both sandwiching members move relative to each other in the opening and closing direction when a hydraulic actuator of the hydraulic drive device is operated. And a hydraulic actuator of the hydraulic drive device.

According to this apparatus, the using the speed increasing mechanism of the hydraulic drive system (hydraulic motor and allowed combination of the auxiliary hydraulic pump), by overdrive the hydraulic actuator, quickly opening and closing the two scissors members Can be made.

  As the sandwiching apparatus, each of the sandwiching members is a crusher that is a crushing member that crushes the processed product by sandwiching the processed product therebetween, or a press device that presses the processed product between molds. Etc. can be applied.

  The crusher includes an apparatus main body connected so that each of the pinching members can be relatively moved in the opening and closing direction, and the apparatus main body includes an attachment support portion whose tip is movable. What has the attaching part attached to the front-end | tip of a support part is suitable. According to this structure, the said pinching processing apparatus can be smoothly transferred to a process target by the action | operation of the said attachment support part.

  Further, the present invention provides an attachment support portion having a tip attached to the attachment processing device, an attachment portion to which an attachment portion of the device main body of the attachment processing device is attached, and the attachment support portion is movable at the tip of the attachment support portion. A work machine in which a hydraulic circuit of the pinch processing device and a hydraulic pump connected to the hydraulic circuit are mounted on the machine body or the attachment support part.

As described above, according to the present invention, by operating a hydraulic pump (auxiliary hydraulic pump ) different from this by the discharge oil of the main hydraulic pump, the main hydraulic pump can be configured with a high degree of freedom in design. There is an effect that effective acceleration can be performed without increasing the capacity.

  A first embodiment of the present invention will be described with reference to FIGS.

  The work machine shown in FIG. 1 includes a machine body 10 capable of traveling and an attachment support portion. This attachment support part is comprised by the boom 12 provided in the said body 10 so that raising and lowering is possible, and the arm 14 connected with the front-end | tip of this boom 12 so that rotation about a horizontal axis is possible. The distal end of the arm 14 can be freely moved by combining the raising and lowering operation of the boom 12 and the rotation operation of the boom 12 and the rotation operation of the arm 14. And the crusher 16 is attached to the front-end | tip of this arm 14 so that rotation around a horizontal axis is possible and detachable.

  As shown in FIG. 2, the crusher 16 includes a crusher body 20. The crusher main body 20 includes an arm connecting portion 18 attached to the tip of the arm 14 and a support column portion 24 connected to the arm connecting portion 18 via a rotation drive mechanism 19 so as to be relatively rotatable.

  The rotation drive mechanism 19 relatively rotates a pair of disk-shaped substrates 22, 30 around its central axis, and the column portion 24 is erected on one of the substrates 22, and the other substrate 30 is The arm connecting portion 18 is erected.

  A first crushing arm 28 </ b> A and a second crushing arm 28 </ b> B are connected to the distal end of the support column 24 so as to be rotatable through left and right support shafts 26, respectively. These crushing arms 28A and 28B have a crushing blade 27 inside thereof.

  A first hydraulic cylinder 40A is interposed between the first crushing arm 28A and the substrate 22. Similarly, a second hydraulic cylinder 40B is interposed between the second crushing arm 28B and the substrate 22. These hydraulic cylinders 40A and 40B simultaneously expand and contract to rotate the crushing arms 28A and 28B in opposite directions. That is, the crushing arms 28A and 28B are caused to perform an opening / closing operation (crushing operation).

  On the other hand, the arm connecting portion 18 has a pair of brackets 32 protruding from the substrate 30, and through holes 34 and 36 are provided in these brackets 32. Of these, a pin for connecting the bracket 32 to the tip of the arm 14 is inserted into the through hole 34, and a cylinder 38 for driving the crusher to rotate the bracket 32 is inserted into the through hole 36 (FIG. 1). ) Is inserted through the pin.

  As shown in FIG. 3, each of the hydraulic cylinders 40 </ b> A and 40 </ b> B includes a cylinder body 42, a piston 43 loaded in the cylinder body 42, and a rod 44 extending from the piston 43 to one side. The piston 43 partitions the inside of the cylinder body 42 into the rod side chamber 45 and a head side chamber 46 on the opposite side.

  FIG. 3 shows a hydraulic drive apparatus including the hydraulic cylinders 40A and 40B. Although the drawing shows both hydraulic cylinders 40A and 40B in common for the sake of convenience, both hydraulic cylinders 40A and 40B are actually connected in parallel to the illustrated hydraulic circuit. Further, the hydraulic drive device according to the present invention can be applied to a device having only a single hydraulic actuator.

  The illustrated hydraulic drive device includes a main hydraulic pump 50 and a hydraulic circuit for connecting the hydraulic cylinders 40A and 40B to the main hydraulic pump 50 in addition to the hydraulic cylinders 40A and 40B. The main hydraulic pump 50 is connected to an output shaft of an unillustrated engine mounted on the machine body 16 and is driven by the engine to discharge hydraulic oil in a tank. The hydraulic circuit supplies the oil discharged from the main hydraulic pump 50 to the hydraulic cylinders 40A and 40B to operate both hydraulic cylinders simultaneously.

  The hydraulic circuit includes a first pump motor 52A and a second pump motor 52B, and a first introduction oil passage 54A for introducing the discharge oil of the main hydraulic pump 50 into the pump motors 52A and 52B, respectively. The hydraulic cylinder 40A uses the second introduced oil passage 54B, the outflow oil passages 56A and 56B for letting out the oil from the pump motors 52A and 52B, and the oil that is the sum of the outflow oils of both outflow oil passages 56A and 56B. , 40B, supply oil passages 58A and 58B for supplying to the head side chamber 46 and the rod side chamber 45, respectively.

An introduction switching valve 60 is interposed between the main hydraulic pump 50 and the introduction oil passages 54A and 54B, and merging supply switching is provided between the outflow oil passages 56A and 56B and the supply oil passages 58A and 58B. A valve 62 is provided. Further, between the first introduction oil passage 54A and the first supply oil passage 58A, the pump motors 52A and 52B and the merged supply switching valve 62 are bypassed so that the oil passages 54A and 58A are connected to each other. A bypass oil passage 64A to be connected is provided, and a variable relief valve 66A with a check valve is provided in the middle of the bypass oil passage 64A. Similarly, between the second introduction oil passage 54B and the second supply oil passage 58B, the oil passages 54B and 58B are bypassed by bypassing both the pump motors 52A and 52B and the merging supply switching valve 62. Is provided, and a variable relief valve 66B with a check valve is provided in the middle of the bypass oil passage 64B.

  As the pump motors 52A and 52B, those that can be used both as a gear pump and a gear motor are used in the illustrated example, and those having the same capacity are used. Specifically, each of the pump motors 52A and 52B includes a housing 70 and a pair of gears 72 and 74 that mesh with each other in the housing 70. The housing 70 includes the introduction oil passages 54A and 54B, respectively. It has an inlet port 70a to be connected and an outlet port 70b to be connected to each of the outflow oil passages 56A and 56B.

  In FIG. 3, for the sake of convenience, the housing 70 and the gears 72 and 74 are shown in an unfolded state. However, in actuality, the pumps 52 and 74 are arranged so that the positions of the rotation axes of the gears 72 and 74 coincide with each other. The housings of the motors 52A and 52B are integrated. The rotation shafts 76A and 76B are connected to each other so that the rotation shaft 76A of the gear 74 in the first pump motor 52A and the rotation shaft 76B of the gear in the second pump motor 52B rotate integrally. 78.

  Accordingly, in these pump motors 52A and 52B, when pressure oil is flowed from the inlet port 70a of one of the pump motors toward the outlet port 70b, the gears 72 and 74 of the pump motor are in the direction of the arrows in the figure. The pump motor functions as a hydraulic motor, and the gears 72 and 74 of the other pump motor are rotationally driven in the direction of the arrow in the figure in conjunction with this, so that the other pump motor is connected to its inlet port. It functions as an auxiliary hydraulic pump that pumps oil from 70a toward the outlet port.

  In the present invention, regardless of the specific structure of each pump motor, in addition to the gear type shown in the figure, for example, a vane type or a piston type can be applied. Further, the “hydraulic motor” and the “auxiliary hydraulic pump” according to the present invention may not necessarily be used both as a pump and a motor, and may be dedicated to the motor and the pump, respectively. The capacities are not necessarily the same.

  The introduction switching valve 60 shown in FIG. 3 is a three-position manual switching valve, and has a neutral position 60a, a first introduction position 60b, and a second introduction position 60c. Here, the neutral position 60a is a position where the main hydraulic pump 50 and the tank are disconnected from the both introduced oil passages 54A and 54B. The first introduction position 60b is a position where the discharge side of the main hydraulic pump 50 is connected to the first introduction oil passage 54A, and the second introduction oil passage 54B is communicated with the tank. The second introduction position 60c is a position where the discharge side of the main hydraulic pump 50 is connected to the second introduction oil passage 54B and the first introduction oil passage 54A communicates with the tank.

  The joining supply switching valve 62 is a two-position pilot switching valve in the illustrated example, and joins the two outflow oil passages 56A and 56B to connect to the first supply oil passage 58A; And a second supply position 62b that joins the two spilled oil passages 56A and 56B and connects to the second supply oil passage 58B. The merging supply switching valve 62 includes a first pilot port 63A to which a pilot pressure for switching the valve 62 to the first supply position 62a is input, and the valve 62 to the second supply position 62b. And a second pilot port 63B to which a pilot pressure for switching to is input, and an urging spring 62c. The biasing spring 62c holds the valve 62 at the first supply position 62a when no pilot pressure is input to the pilot ports 63A and 63B or when an equivalent pilot pressure is input.

  The variable relief valves 66A and 66B with check valves provided in the bypass oil passages 64A and 64B are opened only when the primary pressure is equal to or higher than the set pressure, and the bypass oil passages 64A and 64B are opened. Further, the first pilot port 63A of the merging supply switching valve 62 is connected to the primary bypass oil passage 64A of the variable relief valve 66A with a check valve via a first pilot line 68A. A second pilot port 63B of the merging supply switching valve 62 is connected to a primary bypass oil passage 64B on the primary side of the variable relief valve 66B with a check valve via a second pilot line 68B. Each of the supply oil passages 58A and 58B is provided with a check valve 69 for preventing a back flow from the bypass oil passages 64A and 64B to the merge supply switching valve 62.

  Next, specific actions of the hydraulic drive device and the crusher 16 will be described.

  In this description, a state satisfying the following 1) to 3) is assumed as an initial state.

  1) As indicated by the solid lines in FIGS. 1 and 2, both the crushing arms 28A and 28B of the crusher 16 are in the open position. That is, both hydraulic cylinders 40A and 40B are contracted.

  2) The crusher 16 is transferred to a position where an object to be crushed is interposed between the crushing arms 28A, 28B of the crusher 16.

  3) The introduction switching valve 60 shown in FIG. 3 is switched to the neutral position 60a.

  When the introduction switching valve 60 is switched to the first introduction position 60b from this state, the discharge oil of the main hydraulic pump 50 flows into the first introduction oil passage 54A. Here, while the discharge pressure of the main hydraulic pump 50 is low, since the variable relief valve 66A with a check valve in the bypass oil passage 64A is closed, the discharge oil does not pass through the bypass oil passage 64A. The oil flows into the first pilot port 63A of the merging supply switching valve 60 through the first pilot line 68A connected to the primary side of the variable relief valve 66A with the check valve, whereby the merging supply switching valve 60 is set to the first. Supply position 62a.

  The oil that has flowed into the first introduction oil passage 54A flows from the inlet port 70a of the first pump motor 52A to the outlet port 70b, and operates the pump motor 52A as a hydraulic motor. Further, when the rotary shaft 76B of the second pump motor 52B connected to the rotary shaft 76A of the first pump motor 52A via the connecting shaft 78 rotates in conjunction with the rotary shaft 76A, the first pump motor 52A rotates. The second pump motor 52B operates as an auxiliary hydraulic pump. That is, the second pump motor 52B sucks the oil in the tank into the inlet port 70a of the pump motor 52B through the introduction switching valve 60 and the second introduction oil passage 54B, and flows from the outlet port 70b to the outflow oil passage 56B. Discharge.

  The oil discharged from the second pump motor 52B to the second spilled oil passage 56B and the oil flowing out from the outlet port 70b of the first pump motor 52A into the first spilled oil passage 56A are the first. The merged supply switching valve 62 at the first supply position 62a joins and flows from the first supply oil passage 58A into the head side chamber 46 of the hydraulic cylinders 40A and 40B to extend the cylinders 40A and 40B. Accordingly, oil is supplied to the head side chamber 46 at a flow rate larger than the discharge flow rate of the hydraulic pump 50, and the extension drive of the hydraulic cylinders 40A and 40B is accelerated by the increase in the flow rate. As a result, both the crushing arms 28A and 28B are quickly closed and actuated.

The oil pushed out of the rod side chamber 45 with the extension of the hydraulic cylinders 40A, 40B is the check valve of the variable relief valve 66B with a check valve in the second supply oil passage 58B and the bypass oil passage 64B. Is then returned to the second introduction oil passage 54B and re-supplied from the oil passage 54B to the hydraulic cylinders 40A and 40B.

  When the closing drive of the hydraulic cylinders 40A and 40B as described above proceeds and the crushing blades 27 of the crushing arms 28A and 28B come into contact with the object to be crushed, the hydraulic cylinders 40A and 40B are driven from the contact point. As a result, the discharge pressure of the main hydraulic pump 50 increases rapidly. When the discharge pressure becomes equal to or higher than the set pressure of the variable relief valve with check valve 66A in the bypass oil passage 64A, the valve 66A is opened and the bypass oil passage 64A is opened. As a result, since the discharged oil is directly introduced into the hydraulic cylinders 40A and 40B through the bypass oil passage 64A that bypasses both the pump motors 52A and 52B, the speed-up action disappears, but to that extent, to the hydraulic cylinders 40A and 40B. The supplied hydraulic pressure increases, and the crushing arms 28A and 28B are driven in the closing direction with a force sufficient to crush the object to be crushed.

  After the crushing operation is completed, when the introduction switching valve 60 is switched from the first introduction position 60b to the second introduction position 60c, the discharge oil of the main hydraulic pump 50 is now in a second state. It flows into the introduction oil passage 54B. The discharge pressure of the main hydraulic pump 50 at this time (that is, when the crushing arms 28A and 28B are opened and driven) is generally low, and therefore the variable relief valve 66B with a check valve in the bypass oil passage 64B is closed. Oil does not pass through the bypass oil passage 64B, but flows into the second pilot port 63B of the merging supply switching valve 60 through the second pilot line 68B connected to the primary side of the variable relief valve 66B with check valve. The junction supply switching valve 60 is set to the second supply position 62b.

  The oil that has flowed into the second introduction oil passage 54B flows from the inlet port 70a of the second pump motor 52B to the outlet port 70b, and operates the pump motor 52B as a hydraulic motor. Further, when the rotary shaft 76A of the first pump motor 52A connected to the rotary shaft 76B of the second pump motor 52B via the connecting shaft 78 rotates in conjunction with the rotary shaft 76B, the first pump motor 52A rotates. One pump motor 52A operates as an auxiliary hydraulic pump. That is, the first pump motor 52A sucks the oil in the tank into the inlet port 70a of the pump motor 52A through the introduction switching valve 60 and the first introduction oil passage 54A, and flows from the outlet port 70b to the outflow oil passage 56A. Discharge.

  The oil discharged from the first pump motor 52A to the first spilled oil passage 56A and the oil discharged from the outlet port 70b of the second pump motor 52B to the second spilled oil passage 56B are 2 joins at the joining supply switching valve 62 at the supply position 62b and flows into the rod side chamber 45 of the hydraulic cylinders 40A, 40B from the second supply oil passage 58B, and the cylinders 40A, 40B are extended. Accordingly, oil is supplied to the rod side chamber 45 at a flow rate larger than the discharge flow rate of the hydraulic pump 50, and the hydraulic cylinders 40A and 40B are contracted and driven by the increase in the flow rate, similarly to the driving at the time of extension. Increased speed. As a result, the crushing arms 28A and 28B are quickly opened and operated.

  The oil pushed out of the head side chamber 46 with the contraction of the hydraulic cylinders 40A and 40B is the check valve of the variable relief valve 66A with a check valve in the first supply oil passage 58A and the bypass oil passage 64A. Is then returned to the first introduction oil passage 54A and re-supplied from the oil passage 54A to the hydraulic cylinders 40A and 40B.

  However, even in the operation in the opening direction, if the driving load increases due to some reason, the variable relief valve with check valve 66B is opened and the bypass oil passage 64B is opened, thereby increasing the speed. In other words, the driving state can be switched to the driving force that is more important than the driving force.

  Next, a second embodiment of the present invention will be described with reference to FIG.

  In the hydraulic circuit according to this embodiment, as a means for switching opening and closing of the bypass oil passages 64A and 64B, a bypass switching valve comprising a two-position pilot switching valve in the middle of the first introduction oil passage 54A and the bypass oil passage 64A. 81, and a bypass switching valve 82 comprising a two-position pilot switching valve is provided in the middle of the second introduction oil passage 54B and the bypass oil passage 64B.

  The bypass switching valve 81 has a normal position 81a and an intersection position 81b. The normal position 81a opens the first introduction oil passage 54A and the bypass oil passage 64A as they are, and at the intersection position 81b, The first introduction oil passage 54A and the bypass oil passage 64A intersect each other on the way. Similarly, the bypass switching valve 82 has a normal position 82a and an intersection position 82b. The normal position 82a opens the second introduction oil path 54B and the bypass oil path 64B as they are, and the intersection position In 82b, the second introduction oil passage 54B and the bypass oil passage 64B cross each other on the way. The bypass oil passages 64 </ b> A and 64 </ b> B are provided with check valves 84 that prevent oil from flowing into the valves 81 and 82 at positions upstream of the bypass switching valves 81 and 82.

  The bypass switching valves 81 and 82 are switched by a first pilot line 68A and a second pilot line 68A for switching the merging supply switching valve 62 to the first supply position 62a side and the second supply position 62b side, respectively. This is performed using the pilot line 68B. Specifically, a variable relief valve 86A is interposed between the first pilot line 68A and the pilot port of the bypass switching valve 81. Similarly, the second pilot line 68B and the bypass switching valve 81 are provided. A variable relief valve 86B is interposed between the pilot port and the pilot port.

  In this device, when the introduction switching valve 60 is switched to the first introduction position 60b and the discharge pressure of the main hydraulic pump 50 is lower than the set pressure of the variable relief valve 86A, the discharge pressure is the first. By supplying a pilot pressure to the first pilot port 63A of the merging supply switching valve 62 through the pilot line 68A, the merging supply switching valve 62 is switched to the first supply position 62a. However, the variable relief valve 86A Since the variable relief valve 86B on the opposite side does not open, the bypass switching valves 81 and 82 maintain the normal positions 81a and 82a, respectively.

  Accordingly, the oil discharged from the main hydraulic pump 50 passes through the first introduction oil passage 54A, rotates the first pump motor 52A as a hydraulic motor, and is connected to the first pump motor 52A. The motor 52B is operated as an auxiliary hydraulic pump. That is, the second pump motor 52B sucks and discharges oil in the tank. Then, the discharged oil and the oil flowing out from the outlet port 70b of the first pump motor 52A are merged by the merged supply switching valve 62 at the first supply position 62a, and the hydraulic pressure is supplied from the first supply oil path 58A. It flows into the head side chamber 46 of the cylinders 40A, 40B, and the hydraulic cylinders 40A, 40B are extended. The oil pushed out from the rod side chamber 45 of these hydraulic cylinders 40A, 40B is returned to the second introduction oil passage 54B via the check valve 84 of the bypass oil passage 64B.

  On the other hand, when the driving load of the hydraulic cylinders 40A and 40B increases and the discharge pressure of the main hydraulic pump 50 becomes higher than the set pressure of the variable relief valve 86A, the valve 86A is opened and the discharge pressure is increased. By inputting the pilot pressure to the pilot port of the bypass switching valve 81, the bypass switching valve 81 is switched from the normal position 81a to the crossing position 81b. Therefore, the oil discharged from the main hydraulic pump 50 bypasses the first pump motor 52A and is supplied directly from the bypass oil passage 64A to the first supply oil passage 58A, and the head side chambers of the hydraulic cylinders 40A and 40B. 46 is supplied at a higher pressure.

  Contrary to the above, when the introduction switching valve 60 is switched to the second introduction position 60c, when the discharge pressure of the main hydraulic pump 50 is low, the bypass switching valve 82 maintains the normal position 82a and the merging supply switching. By switching the valve 62 to the second supply position 62b, the discharge oil of the main hydraulic pump 50 is supplied from the second introduction oil passage 54B to the second pump motor 52B, and the second pump motor 52B And the discharged oil of the first pump motor 52A functioning as an auxiliary hydraulic pump in conjunction with the second pump motor 52B are merged by the merged supply switching valve 62 switched to the second supply position. Then, the oil is supplied from the second supply oil passage 58B to the rod side chamber 45 of the hydraulic cylinders 40A and 40B.

  When the discharge pressure of the main hydraulic pump 50 exceeds the set pressure of the variable relief valve 86B for some reason, the variable relief valve 86B opens to switch the bypass switching valve 82 to the crossing position 82b. The oil discharged from the main hydraulic pump 50 bypasses the second pump motor 52B and is directly supplied to the rod side chamber 45 of the hydraulic cylinders 40A and 40B from the bypass oil passage 64B.

  Therefore, also in this device, it is possible to perform speed-up operation switching according to the actual driving load.

Next, an embodiment different from the embodiment of the present invention will be described with reference to FIG.

  The hydraulic circuit according to this embodiment includes a small-capacity pump motor 90 and a large-capacity pump motor 92, and an inlet-side switching valve provided on the inlet side of these pump motors 90 and 92 (that is, the side close to the main hydraulic pump 50). 94, an outlet side switching valve 96 provided on the outlet side of the pump motors 90 and 92 (that is, the side close to the hydraulic cylinders 40A and 40B to be driven), the outlet side switching valve 96 and the hydraulic cylinders 40A and 40B. And a supply switching valve 98 provided therebetween.

  Each of the pump motors 90 and 92 can be used as both a pump and a motor, like the pump motors 52A and 52B in the first embodiment, and one of the input shafts (output when used as a motor). Shaft) and the other output shaft (input shaft when used as a pump) are connected to each other via a connecting shaft 78, but the large-capacity pump motor 92 has a larger capacity than the small-capacity pump motor 90. A large capacity is used.

  Accordingly, when pressure oil flows from the inlet port 90a to the outlet port 90b of the small capacity pump motor 90, the pump motor 90 functions as a speed increasing hydraulic motor, and in conjunction with this, the large capacity pump motor. By driving 92, the pump motor 92 functions as a speed increasing hydraulic pump that pumps oil at a larger flow rate from the inlet port 92a toward the outlet port 92b. Conversely, when pressure oil flows from the inlet port 92a to the outlet port 92b of the large capacity pump motor 92, the pump motor 92 functions as a pressure increasing hydraulic motor, and in conjunction with this, the small capacity pump motor. 90 is driven and functions as a pressure-intensifying hydraulic pump that pumps oil at a higher pressure from the inlet port 90a toward the outlet port 90b.

  In this case as well, various types such as a gear type, a vane type, and a piston type can be applied regardless of the specific structure of each pump motor. In this embodiment, when it is not particularly necessary to add a pressure increasing function, that is, when used exclusively for speed increasing, the pump and motor are not necessarily included in the “speed increasing hydraulic motor” and the “speed increasing hydraulic pump”. It is not necessary to use those that can be used for both the motor and the pump.

The inlet side switching valve 94 is a two-position pilot switching valve in the illustrated example, and has a speed increasing introduction position 94a and a pressure increasing introduction position 94b. Here, the speed increasing introduction position 94a connects the pump oil passage 100 connected to the discharge port of the main hydraulic pump 50 to the inlet port 90a of the small capacity pump motor 90, so that the large capacity pump motor 92 The inlet port 92a is connected to a tank oil passage 102 that communicates with the tank, and the pressure increasing introduction position 94b connects the pump oil passage 100 to the inlet port 92a of the large-capacity pump motor 92 so that the small-capacity pump This is a position where the inlet port 90 a of the motor 90 is connected to the tank oil passage 102. The inlet side switching valve 94 has a single pilot port, and maintains the speed increasing introduction position 94a when no pilot pressure is input to the port, and when the pilot pressure is input, the pressure increasing introducing position. 94b.

  The outlet side switching valve 96 is also a two-position pilot switching valve in the illustrated example, and has a speed increasing supply position 96a and a pressure increasing supply position 96b. Here, the speed increasing supply position 96 a connects the outlet port 90 b of the small capacity pump motor 90 to the cylinder supply oil path 104 and joins the outlet port 92 b of the large capacity pump motor 92 to the tank oil path 102. The pressure increasing supply position 96b connects the outlet port 92b of the large capacity pump motor 92 to the cylinder supply oil path 104 to connect the outlet port 92b of the large capacity pump motor 90 to the outlet port of the small capacity pump motor 90. This is the position where 90 b is connected to the return oil passage 106.

  The outlet side switching valve 96 has a single pilot port, and maintains the speed increasing supply position 96a when no pilot pressure is input to the port, and when the pilot pressure is input, the pressure increasing supply position. It is switched to 96b.

  The pilot port of the inlet side switching valve 94 and the pilot port of the outlet side switching valve 96 are connected to the pump oil passage 100 through a common pilot line 108, and the pilot line 108 has a check valve that is a pressure valve. A variable relief valve 110 is provided. The variable relief valve 110 with a check valve is located closer to the pump oil passage 100 than the pilot ports of the switching valves 94 and 96 (upstream position), and its primary pressure, that is, the main hydraulic pump 50 The pilot line 108 is opened only when the discharge pressure is equal to or higher than the set pressure.

  The supply switching valve 98 is a three-position manual switching valve in the illustrated example, and has a neutral position 98a, a first supply position 98b, and a second supply position 98c. Here, the neutral position 98a is a position where the supply oil path 104 and the return oil path 106 are blocked from the hydraulic cylinders 40A and 40B, and the first supply position 98b is a position where the supply oil path 104 is disconnected. The hydraulic cylinders 40A and 40B are connected to the head side chamber 46 and the return oil passage 106 is connected to the rod side chamber 45 of the cylinders 40A and 40B. The second supply position 98c is connected to the supply oil passage 104. This is a position where the return oil passage 106 is connected to the head side chamber 46 of the cylinders 40A, 40B by connecting to the rod side chamber 45 of the hydraulic cylinders 40A, 40B.

  Next, specific actions of the hydraulic drive device and the crusher 16 will be described.

  In this description, a state satisfying the following 1) to 3) is assumed as an initial state.

  1) As indicated by the solid lines in FIGS. 1 and 2, both the crushing arms 28A and 28B of the crusher 16 are in the open position. That is, both hydraulic cylinders 40A and 40B are contracted.

  2) The crusher 16 is transferred to a position where an object to be crushed is interposed between the crushing arms 28A, 28B of the crusher 16.

  3) The supply switching valve 98 shown in FIG. 5 is switched to the neutral position 98a.

  When the supply switching valve 98 is switched to the first supply position 98b from this state, the variable relief valve 110 with a check valve in the pilot line 108 is closed while the discharge pressure of the main hydraulic pump 50 is low. The inlet side switching valve 94 and the outlet side switching valve 96 maintain the speed increasing introduction position 94a and the speed increasing supply position 96a, respectively. Accordingly, the oil discharged from the main hydraulic pump 50 is guided from the pump oil passage 100 to the small capacity pump motor 90 via the inlet side switching valve 94 and flows from the inlet port 90a of the pump motor 90 to the outlet port 90b. Thus, the pump motor 90 is operated as a speed increasing hydraulic motor. The oil that has flowed through the small capacity pump motor 90 returns to the tank from the outlet side switching valve 96 via the return oil passage 106 and the tank oil passage 102.

  At this time, the large-capacity pump motor 92 connected to the small-capacity pump motor 90 via the connecting shaft 78 is rotationally driven to operate as a speed increasing hydraulic pump. That is, the large capacity pump motor 92 sucks the oil in the tank from the inlet port 92a through the tank oil passage 102 and the inlet side switching valve 94 and discharges it from the outlet port 92b. The discharged oil is supplied to the head side chamber 46 of the hydraulic cylinders 40A and 40B via the outlet side switching valve 96, the supply oil passage 104, and the supply switching valve 98, and extends the hydraulic cylinders 40A and 40B.

  Here, since the large capacity pump motor 92 has a larger capacity than the small capacity pump motor 90, the large capacity pump motor 92 is larger than the oil supply flow rate to the small capacity pump motor 90. Oil is discharged at a flow rate. Accordingly, when oil is supplied to the head side chamber 46 at this large flow rate, the extension drive of the hydraulic cylinders 40A and 40B is accelerated by the increase in the flow rate. As a result, the crushing arms 28A and 28B are quickly closed and actuated.

  The oil pushed out from the rod side chamber 45 as the hydraulic cylinders 40A and 40B are extended returns to the tank via the supply switching valve 98, the return oil passage 106, and the tank oil passage 102.

  When the closing drive of the hydraulic cylinders 40A and 40B as described above proceeds and the crushing blades 27 of the crushing arms 28A and 28B come into contact with the object to be crushed, the hydraulic cylinders 40A and 40B are driven from the contact point. As a result, the discharge pressure of the main hydraulic pump 50 increases rapidly. When the discharge pressure becomes equal to or higher than the set pressure of the variable relief valve 110 with a check valve in the pilot line 108, the valve 110 is opened and the pilot line 108 is opened. As a result, the discharge pressure of the main hydraulic pump 50 is supplied as pilot pressure to the pilot ports of both switching valves 94 and 96, respectively, and these switching valves 94 and 96 are moved to the pressure increasing introduction position 94b and the pressure increasing supply position 96b, respectively. Switch.

  By such valve switching, the discharge oil introduction destination of the main hydraulic pump 50 is switched from the small capacity pump motor 90 to the large capacity pump motor 92. The discharged oil flows from the inlet port 92a to the outlet port 92b of the large-capacity pump motor 92 to operate the pump motor 92 as a pressure-increasing hydraulic motor, and returns from the outlet side switching valve 96 to the return oil passage 106 and tank oil. Return to tank via path 102.

At this time, the small-capacity pump motor 90 connected to the large-capacity pump motor 92 via the connecting shaft 78 is rotationally driven to operate as a pressure-increasing hydraulic pump. That is, the small capacity pump motor 90 sucks the oil in the tank from the inlet port 90a through the tank oil passage 102 and the inlet side switching valve 94 and discharges it from the outlet port 90b. The discharged oil passes through the outlet side switching valve 96, the supply oil passage 104, and the supply switching valve 98 to the hydraulic cylinder 4.
The hydraulic cylinders 40A and 40B are extended by being supplied to the head side chambers 46 of 0A and 40B.

  Here, since the capacity of the small capacity pump motor 90 is smaller than the capacity of the large capacity pump motor 92, the small capacity pump motor 90 is a hydraulic pressure supplied from the main hydraulic pump 50 to the large capacity pump motor 92. The oil is discharged at a higher pressure. Accordingly, by supplying this high pressure oil to the head side chamber 46, the extension driving force of the hydraulic cylinders 40A, 40B is increased, and the crushing arms 28A, 28B have a closing force sufficient for crushing the crushed material. Given.

  The speed increasing action and pressure increasing action described above are performed when the supply switching valve 98 is switched to the second supply position 98c, that is, when pressure oil is supplied to the rod side chamber 45 of the hydraulic cylinders 40A and 40B. The same occurs when 40A and 40B are driven to contract. That is, even during the opening operation of the crushing arms 28A, 28B, when the load is small, quick opening drive is performed by the speed increasing action, and when the load increases, the speed increasing action is switched to the pressure increasing action. A driving force capable of resisting the load is ensured.

  The capacity ratio between the pump motors 90 and 92 can be set as appropriate. As the capacity ratio increases, the speed increase ratio and pressure increase ratio also increase.

  In addition, the present invention can take the following embodiments.

  The present invention is not limited to the one having a plurality of hydraulic cylinders 40A and 40B, and can be applied to a hydraulic drive device in which a single hydraulic cylinder is interposed between the crushing arms 28A and 28B, for example. It is. The hydraulic cylinder is not limited to the hydraulic cylinder, and may include a hydraulic motor or other hydraulic actuator.

-The type of each valve is not particularly limited. For example, electromagnetic switching valves are used for the merging supply switching valve 62 and the bypass switching valves 81 and 82 shown in FIGS. 3 and 4, and these valves are electrically switched and controlled based on the driving load detected by a pressure sensor or the like. You may do it.

  The application target of the hydraulic cylinder device according to the present invention is not limited to the crusher 16. For example, the present invention can also be applied to a press apparatus that moves a metal mold in a direction in which the molds are brought into contact with or separated from each other (that is, opens / closes) and presses a workpiece between the molds.

  The hydraulic circuit shown in FIGS. 3 to 5 may have the pump motors 52A and 52B and the pump motors 90 and 92 incorporated in the main body of the crusher 16, or the main body of the working machine shown in FIG. It may be mounted on the side, for example, the fuselage 10 or the attachment support (boom 12 or arm 14).

  In the former case, a normal hydraulic circuit is mounted on the main body side of the work machine, and the crusher 16 including the pump motor and the like is attached to the tip of the arm 14 to increase the above-described increase. High-speed operation and pressure-increasing operation can be performed, and versatility on the main body side of the work machine can be improved.

On the other hand, in the latter case, it is possible to perform drive control of a plurality of types of pinching devices attached to and detached from the tip of the arm 14 using a common hydraulic pump 50 and pump motor. Furthermore, the pump motor or the like can also be used for speed-up driving of other hydraulic actuators (for example, boom cylinders and arm cylinders). Further, as shown in FIG. 5, by providing a supply switching valve 98 in the downstream supply section of the pump motor or the like, the speed increasing operation or the pressure increasing operation is performed for bidirectional driving of the hydraulic cylinders 40A and 40B. There is an advantage that can be.

It is a general view which shows the example of the working machine with which the crusher which concerns on this invention is used. It is a front view of the crusher. 1 is a circuit diagram showing a hydraulic drive device according to a first embodiment of the present invention. It is a circuit diagram which shows the hydraulic drive device which concerns on the 2nd Embodiment of this invention. It is a circuit diagram which shows the hydraulic drive device which concerns on embodiment different from embodiment of this invention.

DESCRIPTION OF SYMBOLS 10 Airframe 12 Boom 14 Arm 16 Crusher 18 Arm connection part 20 Crusher main body 27 Crushing blade 28A Crush arm 28B Crush arm 40A Hydraulic cylinder 40B Hydraulic cylinder 50 Main hydraulic pump 52A 1st pump motor 52B 2nd pump motor 54A 1st 1 introduction oil passage 54B second introduction oil passage 56A first outflow oil passage 56B second outflow oil passage 58A first supply oil passage 58B second supply oil passage 60 introduction switching valve 60a neutral position 60b first Introduction position 60c second introduction position 62 merge supply switching valve 62a first supply position 62b second supply position 63A first pilot port 63B second pilot port 64A bypass oil passage 64B bypass oil passage 66A check valve Variable relief valve with valve 66B Variable relief valve with check valve 68A IN 68B Pilot line 76A Rotating shaft 76B Rotating shaft 78 Connecting shaft 81 Bypass switching valve 82 Bypass switching valve 86A Variable relief valve 86B Variable relief valve 90 Small capacity pump motor 92 Large capacity pump motor 94 Inlet side switching valve 94a Speed increasing introduction position 94b Pressure increasing introduction position 96 Outlet side switching valve 96a Speed increasing supply position 96b Pressure increasing supply position 98 Supply switching valve 108 Pilot line 110 Variable relief valve with check valve

Claims (7)

A hydraulic drive device comprising a hydraulic actuator, a main hydraulic pump, and a hydraulic circuit that connects the main hydraulic pump to the hydraulic actuator and operates the hydraulic actuator,
The hydraulic circuit is
A hydraulic motor that operates by being supplied with discharge oil of the main hydraulic pump;
An auxiliary hydraulic pump connected to the output shaft of the hydraulic motor and driven by the hydraulic motor to suck and discharge oil in the tank;
An introduction part for introducing discharge oil of the main hydraulic pump into the hydraulic motor;
A merging portion that joins the oil flowing out from the hydraulic motor and the discharge oil of the auxiliary hydraulic pump and guides it to the hydraulic actuator;
Look including a return portion and a return oil flowing from the hydraulic actuator to the tank,
The merging unit has a first supply position for supplying the joined oil to one input port of the hydraulic actuator, and a second supply position for supplying the joined oil to the other input port of the hydraulic actuator. A hydraulic drive device comprising a merging supply switching valve . The hydraulic drive device according to claim 1 , wherein
A first pump motor and a second pump motor that can be used as the hydraulic motor and the auxiliary hydraulic pump;
The introduction section includes a first introduction position where an inlet side of the first pump motor is connected to the main hydraulic pump and an inlet side of the second pump motor is connected to a tank; and the second pump motor An introduction switching valve connected to the main hydraulic pump and switched to a second introduction position connecting the inlet side of the first pump motor to the tank,
The merging supply switching valve switches the merging supply switching valve to the second supply position, and a first pilot portion to which a pilot pressure for switching the merging supply switching valve to the first supply position is input. A pilot switching valve having a second pilot portion to which a pilot pressure is input, wherein the first pilot portion is connected to an inlet side of the first pump motor, and the second pilot portion is A hydraulic drive device connected to the inlet side of the second pump motor. In the hydraulic drive unit according to claim 1 or 2 ,
The hydraulic circuit includes a bypass oil passage for bypassing the hydraulic motor and the auxiliary hydraulic pump to guide the discharge oil of the main hydraulic pump to the hydraulic actuator, and the hydraulic pressure on the inlet side of the hydraulic motor is greater than a certain level In this case, the hydraulic drive apparatus includes a bypass switching valve that guides discharge oil of the main hydraulic pump to the bypass oil passage side. 2. A first sandwiching member and a second sandwiching member that move relative to each other in an opening / closing direction, which is a direction in which they are brought into contact with each other, and sandwich a workpiece when moving in the closing direction, and for driving to open / close these sandwiching members. And a hydraulic drive device according to any one of claims 1 to 3 , and when the hydraulic actuator of the hydraulic drive device is operated, at least one of the sandwiching members and the sandwiching member are moved relative to each other in the opening / closing direction. A pinching processing device characterized in that a hydraulic actuator of a hydraulic drive device is connected. The pinch processing apparatus according to claim 4 .
Each said pinching member is a crushing member which crushes the said processed material by pinching | interposing the said processed material between them, The pinching processing apparatus characterized by the above-mentioned. The pinch processing apparatus according to claim 5 , wherein
An apparatus main body connected to each of the pinching members so as to be relatively movable in the opening and closing direction, and the apparatus main body is attached to the tip of the attachment support portion of a work machine including an attachment support portion whose tip is movable A pinching device having a mounting portion. The pinch processing device according to claim 6 ;
An attachment support portion having a mounted portion to which a mounting portion of the apparatus main body of the sandwich processing device is attached;
A machine body that supports the attachment support part so that the tip of the attachment support part can move;
A working machine, wherein a hydraulic circuit of the pinching device and a main hydraulic pump connected to the hydraulic circuit are mounted on the machine body or the attachment support part.

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